JP3378023B2 - Method for forming high resolution pattern on solid substrate - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention generally relates to a method of forming a patterned film on a solid substrate using a pattern irradiation step. More specifically, the present invention relates to ultrathin films that adhere tightly to a substrate and provide the substrate with desired surface properties. More specifically, the present invention allows multiple regions with widely differing reactivity to be sub-micron lateral resolution (l
The present invention relates to a method of forming on the surface of a substrate by using an external solution. According to the present invention, it is possible to deposit a patterned thin metallization on a semiconductor, dielectric or conductive surface directly on the basis of the difference in reactivity.

Techniques capable of spatially (three-dimensionally) modifying the chemical properties of surface areas are of great importance in various applications, especially in the field of microelectronics. The present invention is particularly useful for making high resolution resists, masks, and conductive paths that are essential in making integrated semiconductor devices.
The present invention is also useful for forming high resolution conductive paths in insulating substrates such as quartz, alumina and organic polymers for printed circuits and microwave circuits.

The process of depositing metal on selected areas of a substrate (commonly referred to as "selective patterning" or "selective deposition") involves both printed circuit fabrication and integrated circuit fabrication. However, these two techniques are dealt with separately in the text, as the required resolutions are quite different.

[0004]

[Prior art]

A. Through continuous efforts to obtain higher-speed electronic devices at lower cost than semiconductor microlithography, methods for efficiently producing high-resolution, high-density integrated circuit components on semiconductor substrates such as doped silicon and gallium arsenide compounds have been developed. It was In one direction, high-resolution patterns, that is, line widths less than 1μ (1μ
^Has been studied, and this field of research is known as microcircuit lithography. For a detailed description of this subject, see L.S. F. Thompson, C.I. G. Willso
n and J. J. Bowden's book, Introdu
action to Microlithograph
y ”, published by ACS Press, NY (1983). Considering the speed of progress in ultra-miniaturization of integrated circuit components up to the present, it is expected that a resolution of about ¼ μ (that is, 0.25 μ) will be required in 10 years. Regarding the current status and future requirements of microlithography technology, the following paper: "The Submicro
n Lithography Labyrinth ",
A. N. Broers, SolidState Te
chology, June 1985, pp. 11
9-126; and "Materials for In
integrated Circuit Process
Technology ", M.A. C. Peckerar,
See Academic Press, 1988.

In the conventional method for manufacturing an integrated circuit, pattern formation on the semiconductor surface is performed by the following general method. Apply a radiation-sensitive organic coating (“photoresist”) to the wafer surface. A pretreatment of treating the wafer with an adhesion promoter such as hexamethyldisilazane is also often used. The coated surface is pattern exposed with radiation, such as light, electron beam, ion beam or X-ray. Irradiation
Either the "flood" method or the "scanning beam" method may be used. The flood irradiation method is a method of simultaneously exposing the entire area to be irradiated, and in order to perform pattern irradiation, an image is projected on the substrate or a mask is inserted between the light source and the substrate. In the beam method, the work surface is divided into small areas or "pixels" and the pixels are exposed sequentially, usually by tracing the desired pattern with a beam. A "positive" resist material is one in which the exposed areas are more soluble, for example by light-induced bond scission. "Negative" resist materials are resist materials that generally have reduced solubility in the irradiated areas due to crosslinking reactions such as condensation or free radical polymerization. After chemical development (eg, treatment with concentrated sodium hydroxide or chlorinated hydrocarbon solvent), a pattern of insoluble organic material remains. Contact with the ion plasma or etchant solution removes the substrate material in the uncoated areas.
Chemical removal of residual organic material reveals recessed "trough" areas that are etched and "plateau" areas that are protected by the resist and therefore are not etched.

In the industrial production of integrated microelectronic circuit components, some conditions to be considered first are the resolution of a feature in a semiconductor substrate; the throughput (thr).
uniformity; reproducibility; and capital and material costs. Multilayer films of vinyl stearate and ω-tricosenoic acid deposited using the Langmuir-Blodgett method can draw lines with line width and line spacing of 60 nm by electron beam irradiation (A. Barraud).
Others, Thin Solid Films, 68 , 1
980, pp 91-100; Broers &
M. Pomarantz, Thin Solid F
ilms, 99 , 1983, pp 323-329).

The beam lithography method has many drawbacks. First, computer-controlled beam systems require significant capital outlay and high maintenance costs. Second, the exposure sensitivity of the resist material is limited, so that it is necessary to sequentially irradiate individual pixels, which requires a much longer time than flood irradiation. Since both the line density and the wafer size are increasing, it becomes more and more necessary to consider the processing capability (that is, the time required to form each element). Thirdly, it is necessary to adjust the resolution of the resist and the resistance to the etching solution in a well-balanced manner. It is known that the energy lost by an electron beam driven into a solid is scattered into an oblong space with a diameter approximately equal to the penetration depth of the electron. The penetration depth increases with the energy of the incident electrons. As a result, the diameter of the exposed area is minimal (assuming the entire film thickness is illuminated) when the penetration depth is equal to the film thickness. Therefore, improved resolution is achieved by the use of thinner resist films such as spin cast organic polymer films or the Langmuir-Blodgett films described above.
However, organic ultra-thin film resists have many problems, such as the presence of inhomogeneities in the film (especially pinholes) and the inability to withstand the intense plasma etching processes used to transfer the resist lines to the underlying substrate. including.

Photolithography processing is the most prevalent technique that gives the best combination of resolution and processing power. At present, there is a limit of 1 for drawing line resolution of microcircuit parts that can be produced on a scale that can be put to practical use in industrial production.
It is of the order of μ. In photolithography, generally, a semiconductor substrate coated with a spin-cast organic resist film having a thickness of 300 nm to 1 μm is irradiated with ultraviolet rays (400 nm or less) according to the pattern to draw a pattern. The degree of resolution improvement is limited primarily by the combination of the wavelength of light used, the composition of the film and the thickness of the photoresist.

It is known in photolithography that the resolution is inversely proportional to the wavelength of the radiation. Therefore,
High resolution is obtained using the shortest wavelength radiation that the resist can be sensitive to. A large number of light sources suitable for UV irradiation can be used, eg mercury lamps, xenon lamps, deuterium lamps, surface plasma emission sources, Nd-Y.
There are optical harmonics generated from AG lasers, excimer lasers and these sources. Most of the high resolution photoresists currently in use are in the near UV (ie 320-4).
00 nm). Far ultraviolet rays (200-320
nm) or VUV (200 nm or less) useful photoresists are few, if any.

The wavelength of ultraviolet rays is in the range of 4 to 400 nm. This range includes near ultraviolet rays (400 to 300 nm), deep ultraviolet rays (300 to 200 nm) and deep ultraviolet rays (200 n).
m or less). Deep UV is strongly absorbed by air and is therefore commonly used in vacuum systems.
For this reason, deep UV is often called vacuum UV.

As described above with respect to beam technology, spin-coated resist films used in photolithography have at least 1/10 μm to prevent pinholes and have adequate plasma etching resistance.
Must have a thickness of several times. Other factors that limit the resolution when using thick films include blurred images in the film, standing waves in the film, Rayleigh scattering due to film inhomogeneity, and third-order photoreaction zones. It is difficult to control the original spread. Spin coating tends to form a film with a thicker edge than in the center.
If the film thickness is uneven, there are problems such as diffraction and defocusing, so that the resolution by contact mask exposure (that is, exposure performed by directly contacting a resist-coated substrate with a mask on which a pattern is drawn) is lowered. Moreover, spin coaters are expensive and the substrates must be coated sequentially (ie, one at a time).

Conventional photoresists generally require a chemical development (ie, removal of soluble resist material) treatment after formation of the pattern. Solvents used in development, especially chlorinated hydrocarbons, are known to be harmful to the environment. In addition, the incomplete dissolution of the resist lowers the resolution (especially the sharpness of the edges) during development.

Another difficulty encountered with known resist films is that the adhesion to the substrate is incomplete or weak, and thus the required resist areas may be stripped from the substrate, rendering the product unusable. . Resist materials are often sensitive to ambient light, moisture and temperature, requiring special handling in their handling.

There are many methods for forming metal paths in a semiconductor substrate. Generally, a thin metallization is deposited over the area of the substrate by vapor deposition or sputtering. Most of the metal is removed after the pattern drawing and development steps. It is believed that no industrial photolithographic method capable of selectively depositing high resolution metal patterns exists to date.

B. Printed Circuits In the manufacture of printed circuits, an adhesive metal pattern is formed on an insulating substrate such as an organic polymer (eg acrylonitrile-butadiene-styrene- or polysulfone) and a metal oxide (eg aluminum oxide). Although many other methods can be used to form the metal pattern, generally as in the case of a semiconductor substrate, a sequence of vapor deposition and patterning followed by removal of most of the metal layer is used.

Using various known procedures, the metal is first selectively deposited only in the desired regions of the substrate. In one such procedure, a polymer substrate is used and the patterned photoresist layer is acid etched and the etched resist surface is contacted sequentially with a solution of a tin salt and a precious metal salt or a mixture of these salts. Activated for metal deposition by simultaneous contact with. After activating the etched surface, the substrate is immersed in the electroless plating bath. A typical electroless plating bath contains metal ions, complexing agents, stabilizers and reducing agents. The reducing agent is
The complex metal ion is reduced to a metal only in the activated region. The plated metal surface itself acts as a catalyst for subsequent metal deposition, and thus the thickness of the plating layer can be adjusted by adjusting the length of time the substrate is immersed in the plating bath. For electroless plating of metals on polymer substrates described in the technical literature (including patents), see F. A. Domino's paper, "Plating
of Plastics--Recent Device
Opportunities ", Chemical Techno
logic Review No. 138, Noes
Data Corporation, New Jer
See sey (1979).

The general method described above was applied to epoxy substrates with 150
It has been used to form patterns with μ resolution (JK Dorey et al., US Pat. No. 4.537,79).
9; Patent date 8/27/85). According to the description of the patent,
Metal lines 100 μm wide are formed on the polyphenylene sulfide substrate using a procedure that uses laser annealing and chemical doping instead of developing and etching steps. These methods involve a considerable number of processing steps and are therefore time-consuming and expensive, especially when compared to the method of the invention.

In order to effect selective activation of the insulating substrate, a stamp or stencil is used to deposit an "ink" containing a reducing metal complex or a redox reagent that reduces the activated metal ions on the surface of the substrate. A method of forming a metal plating layer is also known. The resolution of the metal pattern formed by this method is severely limited by the smallest physical size possible with a stamp or stencil. This general method is used to form metal patterns on ceramic substrates. It is known that a reducing metal complex applied to an alumina substrate via a stencil in the form of a mixture with a polymer binder can be converted into a metal pattern by heat treatment. The drawbacks of this method are the limited resolution of the strokes, the poor adhesion of the metal to the substrate, and the need for expensive ignition processes.

[0019]

[Problems to be Solved by the Invention]

A. Semiconductor Microcircuit Components The object of the present invention relating to the technology of semiconductor microcircuit components is electron beam irradiation or light irradiation, preferably 320 nm or 4 which is the wavelength of near-ultraviolet rays which has been conventionally used.
Patterns can be drawn with high resolution by irradiation with light with a wavelength shorter than 00 nm, no chemical development is required, pinholes are extremely few, adhesion to semiconductor substrates is good, and environmental conditions change more than conventional resists. Long-term contact (eg, several minutes) with a reactive ion plasma that is resistant and can selectively undergo chemical reactions (eg, metal deposition) in exposed or unexposed areas and is currently used to fabricate semiconductor microcircuits. Even underneath, the bondability with the substrate (int
An object of the present invention is to provide a photosensitive film capable of maintaining the engritability. In summary, the main object of the present invention is to provide an ultra-thin film high resolution resist which does not have the drawbacks of the high resolution resists used to date in the manufacture of semiconductor microcircuits.

Another object of the present invention is to provide a method of manufacturing a microcircuit for forming a high resolution pattern on a semiconductor substrate using a conventional electroless plating method.

Another object of the present invention is to form an ultrathin film high resolution resist pattern having good adhesion and etching resistance on a conductive, semiconductor or dielectric substrate.

Yet another object of the present invention is to use standard wet chemistry methods without the need for complicated or expensive equipment such as vacuum systems used in some of the microcircuit fabrication methods currently in use. A method of forming a high resolution metal pattern is provided.

Another object of the present invention is to provide an extremely thin high resolution resist which is stable over a wide temperature range and is sufficiently resistant to high humidity that it does not need to be protected by a dedicated atmosphere control device. It is to manufacture.

Yet another object is to form a high resolution metal pattern that is opaque to visible and ultraviolet light on a substrate that is transparent to visible light and ultraviolet light in order to make, duplicate and repair a lithographic mask. .

B. PRINTED CIRCUIT A primary objective of the present invention, which relates to the technology of printed circuit components, is to provide a fast, simple and inexpensive method of forming high resolution conductive vias on an insulating substrate.

Another object of the invention relating to the technology of printed circuit components is to provide a method by which an adhesive metal pattern can be formed on an insulating substrate.

Yet another object of the present invention relating to the technology of printed circuit components is to provide a method of selectively depositing metal on an insulating substrate.

Another object of the present invention relating to the technology of printed circuit components is to provide a method of manufacturing printed circuits using relatively inexpensive and relatively harmless aqueous electroless plating solutions which are commercially available in large quantities. .

[0029]

The method of forming patterned molecular assemblies on a substrate according to the present invention comprises at least one layer of radiation-reactive material having substantially equal reactivity over one surface. The step of preparing a substrate is included. The surface of the radiation-reactive material is exposed by pattern irradiation to provide spatially separated first and second having different reactivities.
Give rise to an area of. At least one of the first and second regions is provided in order to obtain a patterned substrate.
Two additional material layers are deposited directly.

The present invention may include a method of forming a metal pattern on a substrate by depositing a layer or film that modifies the reactivity of the substrate on the surface of the substrate. Preferably, the catalyst precursor is deposited only on the regions of the film that have sufficient reactivity to bind to the catalyst precursor, then the substrate is placed in an electroless metal plating bath, and the region where the catalyst precursor is deposited is placed on the metal plating layer. To do. Preferably, the substrate is a type of substrate having a polar functional group on its surface, and the monomolecular film is a self-assembled film made of a monomer or polymer and deposited on the surface of the substrate.

A feature of the present invention is that high-resolution conductive paths having a separation distance of 0.1 μ or less can be formed. The invention is particularly important in connection with semiconductor microlithography, electrical device fabrication, printed circuit fabrication, mask duplication, fabrication and repair, and the like.

[0032]

Preferred Embodiments Some terms used in the text are defined below. The term "ultra-thin film" means a film or layer having a thickness of at least one molecule. The thickness of the film used is often less than about 1/4 the wavelength of the light used to expose the substrate, and may be as thin as the monolayer.

The term "radiation-reactive material" means a material which is reactive to radiation and which can absorb the radiation used for exposure and consequently be modified. Preferably,
The radiation-reactive substance absorbs light having a wavelength of less than 400 nm. More preferably, the radiation-reactive material has an absorption maximum at the wavelength used to expose the material. Radiation-reactive substances include organic, inorganic and polymeric substances. Examples of polymeric substances include polyether, polyurethane, polysulfone, polystyrene, polyamide, polymethacrylate, polybutadiene, polyethylene terephthalate,
There are paraffins, polyisoprenes and blends and copolymers of such substances. Examples of the inorganic substance include chlorosilane, methoxysilane, ethoxysilane, silazane, titanate and zirconate.

The term "radiation" means any electromagnetic wave that modifies the reactivity of the surface to be treated. In conventional photolithographic methods using thick (eg, 1 μ) photoresist, the total resolution of the method is directly proportional to the wavelength of light that alters the reactivity of the film or layer. Therefore, in the method described in the claims, preferably 0.5 μ
A radiation shorter than 500 nm is used to obtain a theoretical resolution of less than 500 nm, and more preferably a radiation shorter than 250 nm is used to obtain a theoretical resolution of less than 0.25 μ. In this method, an ultra-thin film which is considerably thinner than the wavelength of the pattern writing irradiation line can be used, so that in order to obtain a line drawing resolution of the order of 10 nm, a near light wave
It is also possible to use ld optics). Regarding near light waves, U.S.P. Durig et al., “Near
-Field Optical Scanning Mi
crosscopy with Tunnel-Dist
ance Regulation ", IBM J. Re
s. Development. , Vol. 30, p478 (19
26). The term "resolution" means the spacing or line width of deposited lines, such as metal lines. The line thickness, or metal deposit height, is very small, in the Angstrom range or slightly higher. The pattern irradiation is performed using any of the conventionally known methods, for example, direct writing with an electron beam or a laser beam, step-and-repeat type projection, proximity (proximity) printing, contact (contact) printing, and the like.

The term "catalyst precursor" is a term commonly used in the field of electroless plating and refers to a compound or particle capable of electrolessly depositing a metal on the area of a substrate to which it is attached. , For example palladium / tin colloid.

The term "pattern-wise molecular assembly" refers to
By a structure deposited on the surface of a substrate to conform to a preselected pattern. This pattern is drawn by pattern irradiation. The molecular assembly may be a single layer of one substance or multiple layers of the same or different substances. These materials include inorganic and organic materials such as semiconductors, metals, and combinations thereof. For example, the first layer may consist of a metal, eg palladium, bound to the most reactive of the spatially different reactive areas, and the second layer may consist of another metal, eg copper, bound to palladium. . Additional layers may be further provided depending on the requirements of each specific application. Alternatively, a radiation-reactive material such as a particular chlorosilane may be exposed and then a second chlorosilane may be selectively deposited in the most reactive areas.
The first reactive material is UTF4 and the second reactive material is UT
If F3, UTF4 will bind to the unexposed areas, and thus UTF3 will only bind to the exposed areas. In addition, the molecular assembly is deposited by introducing a palladium-tin colloid that binds to the most reactive of the spatially different reactive regions, then forming a third layer, for example a nickel layer, on top of which. Four layers may be formed, for example a copper layer. The molecular assembly in this case is UTF3 / Pd-
It may be a sandwich structure of Sn / Ni / Cu.

"Spatially different reactive regions" are composed of high resolution patterns of various chemistries that result when the radiation-reactive material of the surface layer is pattern-exposed at an appropriate irradiation wavelength. . The spatially different reactive regions can be arranged in a single plane or in a three-dimensional region and consist of layers having a thickness of at least one atom of a substance such as an inorganic, organic, polymer, metal or semiconductor. Organic materials include aliphatic unsaturated and aromatic hydrocarbons, methacrylates, amines, halocarbons, esters, ethers, polymers and the like. Inorganic materials include silicon oxides, titanium oxides, zirconium oxides, aluminum oxides, platinum oxides, copper oxides and the like and mixtures thereof.

The term "colloidal affinity" refers to the property of preferentially attracting colloidal particles in the area of a substrate or film.

The metal material useful in the present invention is platinum,
There are gold, copper, nickel alloys, palladium and other materials known to provide conductivity or other properties.

As used herein, the term "conductive path" is intended to be used as a conductor, for another purpose in another electronic device such as a semiconductor, or for decoration or other purposes. Means all kinds of patterns.

The molecular assembly of the present invention can form electrical devices such as printed circuits, semiconductors, capacitors and the like. Electrical devices, such as printed circuits, have high resolution, good electrical conductivity of the metal layer and good adhesion of the metal layer. Similarly, semiconductor devices manufactured according to the present invention have high resolution and meet standard electrical requirements.

In accordance with one embodiment of the present invention, high resolution selective metallization on a silicon substrate comprises silanizing a silicon wafer substrate and a monomolecular silane layer covalently bonded to the substrate by terminal olefin groups exposed at the interface. It becomes possible by forming. The energy of UV light is comparable to the covalent energy, so it is possible to cleave the covalent bond in two, known as photolysis. In the present invention, ultraviolet rays are used to cause a photolysis reaction in a thin film (silane film or the like). For this purpose, X-rays are applied to the surface of the wafer covered with the film,
Electron beam, or vacuum UV (preferably 210 to obtain the maximum resolution possible although longer wavelengths can be used)
UV light having a wavelength of less than nm). However, the radiation must have sufficient intensity and wavelength to cleave some regions of the membrane. The colloidal palladium / tin (Pd / Sn) catalyst precursor is coated on the surface of the wafer without treating the irradiated wafer in an intermediate development stage. This material adheres only to the non-irradiated areas of the film. Then, immersing the wafer in the electroless plating bath,
The metal is deposited only in the areas activated by the Pd / Sn catalyst.

The main feature of the present invention is that colloidal palladium / tin (Pd / Sn) is shown schematically in FIG. 3A.
The catalyst precursor is only deposited on the areas of the substrate to be plated by the electroless bath. A catalyst layer having a desired pattern is formed, and the remaining steps of the electroless plating method schematically shown in FIG. 3A are performed. A typical electroless plating method is described in J.
Henry, Metal Finishing Gu
ideabook Directory, Vol. 86,
pp 397-414 (1988).
According to one aspect, the invention is characterized in that the thin film is arranged between the substrate and the catalyst layer so that the thin film strongly adheres to the substrate,
It may be considered that the catalyst is selectively attached to the high resolution pattern formed on the film.

There are many substances that can form thin films that act as spacers, that is, molecules that can self-assemble under appropriate conditions. Generally, such self-assembling molecules have a polar end and an apolar end having a reactive moiety at or near the opposite end of the polar end, typically saturated or unsaturated. An intermediate region consisting of a hydrocarbon chain of In some cases, as in the case of UTF4, the intermediate area is not included. The spacer may consist of either a monomer or a polymer.

The polar end group (which interacts with the polar surface of the substrate) is of the formula: RnSiXm where R is an organic functional group; n is a number of 1, 2 or 3; m = 4-n; and X is a halogen. ,
Alkoxy or amine] silane.

Further examples of polar end groups are carboxylic acids,
There are acid chlorides, anhydrides, sulfonyl groups, phosphoryl groups, hydroxyl groups and amino acid groups.

Examples of groups of non-polar end groups are olefins, acetylenes, diacetylenes, acrylates,
There are aromatic hydrocarbons, methacrylates, methyls, perfluorinated hydrocarbons, primary amines, long chain hydrocarbons and esters.

Examples of substrates which either have polar functional groups on their surface or which have been provided by treatment include silica (quartz and glass), silicon (doped and undoped), other semiconductors (eg germanium, gallium arsenide compounds). ) Or organic polymers such as epoxies, polysulfones, metals and metal oxides such as alumina.
The bifunctional molecule may be attached to the substrate by a variety of procedures including chemical reactions, photochemical reactions, catalytic reactions or other reactions.

In this case, as described above, the outer layer of the substrate forming the monolayer may be the same as the body of the substrate and integral with the substrate, or may be a thin film separately provided by a different material. Well, it can be polar or non-polar, depending on the particular application.

The method of forming the self-assembled thin film used in the present invention provides a uniform unimolecular ultrathin film (less than about 200 nm) having accessible reactive groups on the outer surface. Various methods may be used to modify the reactivity of these groups. When selecting a method, the desired resolution of the pattern to be formed in the film is considered as one of the determinants or factors of the method. One of the various methods is to render the substrate non-reactive or less reactive by photolytic cleavage of the monomolecular structure. As a result, olefins can also generate hydroxyl groups as a result of being made more reactive by oxidation to certain coupling agents (eg, appropriately modified biomolecules, catalysts and spectroscopic probes). Because the reactivity of certain regions of the thin film is modified, chemical reactions can occur (1) only in the regions where the reactivity has changed, or (2) everywhere except the changed regions. Therefore, an important effect of the present invention is to generate sites having various chemical reactivities in the film with high resolution and to attach the catalyst precursor to the electroless plating bath only to the reactive parts.

The substrate is a semiconductor silicon wafer (p-type, n-type
In either form or intrinsic silicon), the film may be formed from a monolayer of self-assembling silane. Non-limiting examples of this type of silane include 7-octenyldimethylchlorosilane, 5-hexenyldimethylchlorosilane and other known chlorosilanes, as well as other known silicon materials, methoxysilanes, polysiloxanes,
There are ethoxysiloxanes, 4-aminobutyldimethylmethoxysilane and 1,1,1,1,3,3,3-hexamethyldisilazane. The film is anchored to the silicon substrate by chemical and physical adsorption, including siloxane (Si-O-Si) bridges and van der Waals forces. Any substrate having ionizable terminal hydroxyl groups on its surface can anchor the silane film. This method using a self-assembled monolayer involves the formation of covalent bonds between the monolayer and the substrate, whereby the membrane is physically adsorbed (physiso).
rbed) Langmuir-Blodgett film can adhere to a substrate more strongly.

Next, referring to FIG. 1A. FIG. 1A schematically shows a process of forming a self-assembling silane monolayer on a solid substrate by adsorbing silane molecules from a silane solution on the surface of the solid substrate 1. In this schematic,
The silane molecule has a "polar" head 2 at one end which is attached via a hydrocarbon chain to a non-polar functional group present at the other end of the molecule. The tail may have a reactive portion 3 or a non-reactive portion 4 shown on the left and right sides of FIG. 1A, respectively. As schematically shown in FIG. 1B, when the non-polar functional group has a reactive moiety 3, this end group is indicated by a triangle symbol, and when the end group has a non-reactive moiety 4,
This group is indicated by the * symbol. The spacer 5 may be any substance that connects the head and the tail, and is, for example, an aliphatic or aromatic linear or branched hydrocarbon having 20 or less carbon atoms which may contain a hetero atom.

By irradiating selected regions of the silane monolayer with ultraviolet light in the manner shown in FIG. 2, the reactive moieties of the irradiated silane molecules are photoinduced and cleaved. Figure 3
As shown schematically in A and FIG. 5B, when the Pd / Sn colloidal catalyst 6 is spread on the surface of the wafer, the colloidal catalyst binds only to the catalytically adhering portions of the interface. The catalyst does not attach to groups that have reactive moieties that have been deactivated by exposure to radiation or groups that have moieties that do not adhere well to the colloid, such as UTF4. When the wafer is immersed in the electroless plating bath, as shown in FIG. 3A, only the portion where the Pd / Sn catalyst precursor is attached to the silane monolayer is plated. When the substrate on which the metal pattern 7 is formed is treated by ion etching, a metal-coated plateau (metal top plate) is formed after the etching, as schematically shown in FIG. 4A.
d plateaus) remains. The metal coating may be removed with an oxidizing acid. Masking and etching steps, procedures and materials known in the field of semiconductor microlithography and printed circuits such as those listed in the prior art section may be used in the present invention.

[0054]

EXAMPLE 1 An n-type silicon wafer having a natural oxide surface (Mo
manufactured by Nsanto, St. Louis, MO) was washed by standard methods. After washing, the wettability of the surface with distilled water distilled three times was measured with a Zisman type contact angle meter, and a measurement value of 0 ° was obtained. This value indicates that the surface is extremely hydrophilic (ie the surface is wetted by a film of water spread on the surface).
Is shown. 1% on the surface of silicon wafer
(V / v) 7-octenyldimethylchlorosilane (U
TF1) (Petrarch Co., Bristo
l PA) in toluene solution at room temperature
It was maintained for a sufficient time (for example, 15 minutes) for the monomolecular film of 1 to be chemisorbed to silicon. The wafer on the hot plate was baked in air at a temperature of about 100 ° C. for 5 minutes to remove residual solvent from the film. The silanized surface was extremely hydrophobic (ie water repellent) with a contact angle with water of 85 °.

XD2408-T Palladium Chloride / Tin Chloride Colloidal Activator (MacDermid)
Co. , Waterbury, CT) was used as received. The silanized wafer surface was coated with Pd / Sn colloidal activator for 5 minutes. The wafer was then thoroughly washed with water. The surface of the wafer was obviously hydrophilic. This indicates that the colloid has bound. The wafer was then immersed for 5 minutes in a Metex 9027 electroless copper plating bath prepared according to the manufacturer's (MacDermid) instructions. The wafer taken out of the bath was thoroughly washed with water. A metal coating of copper was observed on the surface of the wafer. When observing the surface of the wafer with a scanning electron microscope,
It was found that there was a uniform continuous metal coating on the surface of the wafer.

Example 2 Using a similar n-type silicon wafer (made by Monsanto) with a native oxide surface, the procedure of Example 1 was eliminated with the step of silanating the surface of the wafer with UTF1 removed. The same treatment as in Example 1 was performed except that the immersion time was extended. After soaking in the electroless copper plating bath for 15 minutes,
There were only a few small irregularly distributed metal patches on the wafer surface.

Example 3 An n-type silicon wafer with a native oxide surface (Mo
Nsanto) was silanized using the procedure of Example 1. The wafer was then maintained under an argon atmosphere with a mercury / argon lamp (Orie) 3 cm away from the wafer.
l Co. , Stamford CT)
Irradiate for 0 minutes. The illuminance of ultraviolet rays 3 cm away from the irradiation surface of the wafer was measured with a Mamir ultraviolet dosimeter, and a measured value of 4.3 mW / cm ² was obtained. No copper plating layer was present on the wafer after immersion in the copper plating bath used in Example 1 for 15 minutes.

Example 4 An n-type silicon wafer having a natural oxide surface (Mo
(manufactured by Nsanto) was washed by a standard method and silanized by the procedure of Example 1. After removing the residual solvent, the wafer was allowed to cool to room temperature. A low resolution metal mask was placed in mechanical contact with the silanized surface to block light in selected areas. Then, while maintaining the wafer in an inert gas atmosphere of argon, a mercury / argon (Hg / Ar) lamp (O
riel Co. , Stamford, CT) was flood irradiated with UV light for 10 minutes. The illuminance of ultraviolet rays 3 cm away from the wafer surface was measured by a Mamir ultraviolet dosimeter, and a measured value of 4.3 mW / cm ² was obtained. The measurement wavelength of this ultraviolet ray was 254 nm. After irradiating the ultraviolet rays, the wafer surface is treated with XD2408-T palladium chloride / tin chloride colloidal activator (MacDe
rmid Co. ) For 5 minutes. The wafer was then thoroughly washed with water. Only the areas of the surface that were not irradiated were hydrophilic. These results indicate that the olefinic silane strongly interacted with the Pd / Sn colloid. Then as in Example 1, Metex 9027 C
Immersing the wafer in the u bath for 5 minutes formed a thin copper plating layer that duplicated the lines of the masked area. When the mask used has a large number of metal deposition patterns, the metal lines are very close to each other with high resolution and the boundaries with the non-metallized areas are well defined.

Example 5 An n-type silicon wafer with a native oxide surface was silanized using the procedure of Example 1 except that a toluene solution containing 2% (v / v) UTF1 silane was used. The silanized wafer was irradiated for 15 minutes through a photolithographic mask made of a chromium film formed by an electron beam on a quartz substrate. Before silanizing the wafer, the manufacturer (S
hipley Company, Newton, M
Pd / Sn colloidal activator was prepared from Cataposit 44 concentrate and solid Cataprep 404 as instructed in A). In addition, the manufacturer (Shipl
328A and 328 as prescribed by eyCompany)
An electroless copper plating bath was prepared from the Q stock solution.

After irradiation, the wafer was coated with Shipley colloid for 5 minutes using the photolithography method. After thoroughly washing with distilled water, the wafer was immersed in a copper plating bath for 2 and a half minutes. After washing the wafer with water, the surface of the wafer was observed with a bright-field reflection microscope. According to this observation, the pattern of the mask was duplicated on the wafer with copper. SloanDe
The thickness of the copper film measured by the ktak profile meter is 20n.
It was m. The conductivity of the film measured with a two-point probe device was 5000 mho / cm.

The wafer on which the copper pattern is formed is placed in the Pla
smatherm Model 54 reactive ion etching system (Plasmatherm C
o. , Crescent, N .; J. ) And contacted with CF ₄ plasma for 5 minutes. The silicon substrate was etched under normal conditions at an etching rate of 0.1 μ / min to a total depth of 0.5 μ. Nikon Optipho
t M differential interface
When the wafer was observed with an ence contrast Nomarski microscope, it was found that the wafer was etched to a depth of 0.5 μ in all places except the lower part of the copper plating layer. Line width 5μ, spacing between adjacent lines 5μ
Lines and other patterns (edge resolution about 1 μ) were replicated in the silicon wafer as raised areas or plateau areas above the etched surface. It is clear that the copper pattern acted as a high resolution positive resist layer. Ke the etched wafer
When observed by X-ray fluorescence line scanning with an ISI scanning electron microscope equipped with a vex energy dispersive X-ray spectrometer, it was found that copper remained in the raised areas, which was due to the copper plating layer being in ion plasma. Prove that 5 minutes remained.

Example 6 An n-type silicon wafer on which a copper pattern was formed was produced by the procedure of Example 5. However, a quartz-chrome photolithographic mask with micron-sized lines was used to create the pattern. Before CF ₄ plasma etching a silicon wafer on which a copper pattern is formed,
Microscopic examination of the wafer revealed that the copper pattern on the surface of the wafer was a good replica of the mask pattern. After the wafer was plasma-etched for 5 minutes, the wafer was taken out of the etching apparatus and observed with an electron microscope. The resistance of the copper plating to plasma etching was evident in the metallized areas where about 40 nm thick copper remained in the raised areas. The line drawn on the wafer is, for example, about 1 cm long and less than 2 μ wide, 4 μ long.
And a line having a width of about 1/2 μ, a rectangular recess (that is, a trough) having a side of about 5 μ.

Example 7 The procedure of Example 4 was repeated using a p-type silicon wafer (manufactured by Monsanto). As in Example 4, a thin copper plating layer was formed on the wafer to reproduce the lines drawn in the masked area. No significant difference was identified between the plated layer on the p-type wafer and the n-type wafer.

Example 8 1% 5-hexenyldimethylchlorosilane (UTF
2; Petrarch Co. , Bristol P
The procedure of Example 1 was repeated using a toluene solution containing A). The wafer was irradiated and then copper plated as in Example 5. There were no apparent differences between the metal patterns replicated on the UTF2 treated surface and the UTF1 treated surface, respectively.

Example 9 This example demonstrates the patterning of polycrystalline silicon (polysilicon) using 4-aminobutyldimethylmethoxysilane (UTF3).

Polysilicon is the most commonly used material for forming gate and interconnect structures with the highest resolution required for microcircuit fabrication. UTF3 is 7-octenyldimethylchlorosilane (UTF1) in that the polar end of the molecule reacts with the hydroxyl groups on the surface of the substrate.
And 5-hexenyldimethylchlorosilane (UTF2)
Is a surface silanizing agent similar to. However, UTF
3 liberates CH ₃ OH instead of HCl as a by-product of the surface reaction. UTF3 also differs from the previous two silanes in that the non-polar end has a terminal primary amine group rather than an olefin. It is known in the electroless plating industry that amino groups are preferred for attaching Pd / Sn colloidal catalysts prior to metal deposition. Amino groups can be used on the silicon surface instead of olefin groups for high resolution metal pattern formation.

CVD in Bruce 735 furnace at 625 ° C.
4000 Å of polysilicon was deposited on a p-type silicon wafer by. The wafer was then cleaned by standard methods. The contact angle was 0 °. The wafer was immersed in a 2% (v / v) solution of UTF3 in toluene under an argon atmosphere for 5 minutes. The wafer was placed on a hot plate, baked at 100 ° C. for 2 minutes, and the contact angle was measured to be 76 °. The treated wafer was divided into two and one was contacted with the colloidal Pd / Sn activator for 5 minutes. The colloid was removed and the wafer was washed with distilled water. The wafer was then immersed in the electroless copper plating bath for 2 minutes. A continuous film of copper was formed on the wafer. The results show that the primary amines are another example of surface anchoring functional groups (other than the olefinic groups) that can bind to the colloidal Pd / Sn and consequently catalyze metal deposition.

The other half of the wafer is passed through the mask 2
Irradiation was carried out for 30 minutes with a Hg / Ar pen lamp separated by cm.
The wafer was then plated to form a smooth continuous film of Cu only in the areas shielded by the mask.

Example 10 An excellent way to obtain information about ultrathin film molecules is the use of infrared spectral analysis with an attenuated total reflection (ATR) cell with signal amplification. 45 ° silicon crystal (Harr
ick Co. , Ossining NY) was treated with UTF1 as described in Example 1. Wilk the crystal
s Scientific 9000 ATR cell, and using a PE-1800 spectrometer under a nitrogen atmosphere at a crystal critical (Cut) of 4000 cm ^-1 to 1500 cm ^-1.
scanning 16000 times. The spectra obtained were corrected by subtracting the spectra of pure untreated crystals. The peaks due to the hydrocarbon region of the UTF1 film were observed, and 2854 cm ⁻¹ (symmetric CH ₂ stretch), 2924 cm ⁻¹ (asymmetric CH ₂ stretch), 2956 cm ⁻¹ (asymmetric CH ₃ stretch), 2
998 cm ^-1 (symmetrical CH ₃ stretch) and 3078c
Determined to be m ^-1 (vinyl stretch). Two KRS-
Almost the same peaks were observed in the spectrum of pure UTF1 liquid spread between 5 plates (Wilks Scientific). The peak is 3077 cm ^-1 , 2
996cm ^-1, 2956cm ^-1, which is observed in 2927Cm ^-1 and 2857cm ^-1. The small shift to the low energy side and the narrowing of the peak width of the monolayer spectrum indicate that the monolayer has a higher order than pure liquids.
d).

The thin film was then irradiated with a Hg / Ar lamp for 30 minutes. The background-corrected crystal spectrum after irradiation was featureless, indicating cleavage of the monolayer from the surface. This observation allows the introduction of another molecule at the same site in lieu of the photochemically cleaved molecule so that the chemical moieties that can react to form a high lateral resolution pattern.
This suggests that there is room for expanding the range of selection of the “moiety”.

Example 11 Formation of High Resolution Copper Pattern on Alumina (Al ₂ O ₃ ) Highly Polished Microwave Quality Alumina (Al
₂ O ₃ ) wafer (EI Dupont de Nem
ours Co. ) By standard method (contact angle 0
°) and treated with UTF1 as in Example 1 (contact angle = 82 °). The wafer was irradiated with a Hg / Ar lamp through the mask for 30 minutes. Wafer by standard copper plating method 4
Plated for minutes, then rinsed with water. Copper was deposited only on the masked areas. The resistance of the copper layer was measured by the two-point probe method to be less than 0.1 ohm / cm, indicating that the copper film is continuous and highly conductive. The adhesion of the copper pattern was tested by adhering Scotch tape to the alumina wafer and then peeling it off. Copper did not adhere to the Scotch tape. Even after repeating this test a plurality of times, copper did not peel off from the surface of the alumina.

The results show that the method of the present invention can be used to form high resolution contact metal patterns on ceramic substrates such as alumina used in the fabrication of microwave communication circuit components.

Example 12 Formation of Metal Pattern on Silicon Nitride (Si ₃ N ₄ ) Silicon nitride is a conventional dielectric material for silicon microcircuit fabrication.

A 1/2 μm thick silicon nitride film was deposited on a p-type silicon wafer. The wafer was cleaned by standard methods and treated with UTF3 using the procedure of Example 9 (contact angle = 62 °). Through a single level (single height) transistor mask with a chrome layer on a quartz substrate,
The wafer was irradiated with a Hg / Ar lamp for 30 minutes. SU
The mask was brought into close contact with an SS MJB 3 contact aligner. When the patterned film was metallized by standard copper plating, a drawn line having a small line width with a structure of 0.5 μ was obtained.

The results show that silicon nitride is one of the substrate materials that can be used in the method of the present invention to form high resolution metal patterns using commercially available contact aligners. The contact aligner system improves the mask-substrate contact in contrast to the mechanical contact method described in Example 4. Such improved contact can suppress optical aberrations such as shadowing and diffraction.

Example 13 Silicon oxide (CV deposited by chemical vapor deposition)
Formation of Metal Pattern on D Oxide) CVD oxide is a dielectric material commonly used in silicon microcircuit fabrication.

A 1/2 μ thick CVD oxide layer was deposited on p-type silicon in a 300 ° C. CVD furnace. The wafer was washed, treated with UTF3 as in Example 9 (contact angle = 76 °), and a high resolution copper pattern was formed on the wafer by the exposure and plating method described in Example 12.

The results show that metal patterns can be formed on the CVD oxide using the claimed method.

Example 14 Formation of Metal Pattern on Thermally Grown Silicon Dioxide (Thermal Oxide) Thermal oxide is a dielectric material commonly used in silicon microcircuit fabrication.

Thermco model at 1000 ° C.
A layer of thermal oxide having a thickness of 50 nm was grown on n-type silicon in a 201 furnace. A high resolution copper pattern was formed on the wafer using the procedure described in Example 12.

The results show that the method of the invention can be used to form metal patterns on thermal oxides.

Example 15 Formation of High Resolution Metal Pattern on Quartz A quartz slide (ESCO Products) was washed and treated with UTF1 as described in Example 1, ie a film was formed (contact angle = 78 °). A pattern was drawn on the film as described in Example 4 and metallized as described in Example 4. Below, a continuous copper pattern having a line width of 1 μm was observed.

The results show that a high resolution metal pattern can be formed on quartz, and thus a mask for microlithography can be prepared by the novel method of the present invention.

Example 16 Formation of High Resolution Metal Pattern on p-type Silicon Using Argon Fluoride (ArF) Excimer Laser as Source The p-type silicon wafer was cleaned and UT as in Example 1.
It was treated with F1 (contact angle 80-85 °). 193 nm
Lambda Physik model released at
The film was illuminated with a 103 ArF excimer laser through a high resolution mask (mechanical contact). Beam is 0.8
It was a rectangular beam of cm × 3.0 cm. The intensity of the beam before and after irradiation is measured by the Sciencetech model, respectively.
It was measured with a 365 power energy meter and a thermopile detector. The pulse repetition rate was 4 Hz in any irradiation. A total dose of 1 was applied to the membrane with a pulse intensity of 23 mJ / cm ^2.
Exposures up to 1.5, 23 and 46 J / cm ² with a pulse intensity of 20.8 mJ / cm ² and a total dose of 1.5, 3.1, 1
It was exposed to 1.5, 23, 46 and 92 J / cm ² .
The film was metallized by the standard plating method of Example 5. 0.6μ for all values of total dose and pulse intensity used
A high resolution copper pattern with fine lines was formed on the wafer. The amount of metal deposited from the outside is 11.5
The minimum amount was shown at J / cm ² . When a dose of 23 J / cm ² or more is used, a considerable amount of unnecessary plating layer is produced, and this tendency becomes remarkable as the total dose increases.

This result indicates that 193 nm light can be used to write a pattern on UTF1 and that the dose range (dosa) is about 20 to 23 mJ / cm ² of pulse intensity.
It is about 10 to 20 J / cm ² or less.

Example 17 Formation of High Resolution Metal Pattern on Alumina Using ArF Excimer Laser as Irradiation Source The alumina wafer was cleaned and UFT was carried out as in Example 11.
Treated with I. The film was irradiated with a pulse intensity of 20.8 mJ / cm ² to a total dose of 40, ²⁰ , 15 and 10 J / cm ² . The film is then selectively metallized with copper, with a linewidth of 1 below.
High resolution metal patterns down to μ were formed. As in Example 16 using a silicon substrate, an extra plating layer was formed at the higher dose, that is, at a total dose of 20 and 40 J / cm ² , but at the lower total dose, the extra plating layer was completely removed. Or little formed.

The results demonstrate that the dose required for pattern formation is not a function of the substrate on which the film is formed.

Example 18 Vapor Deposition (CVD) Using ArF Excimer Laser
Formation of High Resolution Metallic Pattern on Oxide A p-type silicon wafer having a 1 / 2.mu. Thick CVD oxide layer was treated with UTF3 as described in Example 12. A pattern was drawn by irradiating the film through the mask with an ArF excimer laser in the same manner as in Example 16 except that the pulse intensity was considerably reduced. Repeated pulse 15H with pulse intensity of 0.45 mJ / cm ²
Used at z to give a total dose of 13.8 J / cm ² . The wafer was then metallized by the standard copper plating method used in Example 9. A high resolution (line width 0.5 μ) metal pattern was formed on the wafer.

This result demonstrates that reducing the pulse intensity by two orders of magnitude and increasing the pulse repetition rate has no apparent effect on the total dose range. It is also found that the dose range for UTF3 is almost the same as that for UTF1 using 193 nm light.

Example 19 Formation of High-Resolution Metal Pattern on Polysilicon by ArF Excimer Laser A p-type silicon wafer having a polysilicon layer with a thickness of ½ μm was treated with UTF3 in the same manner as in Example 9. 20Hz repetition rate of pulse with pulse intensity 0.29mJ / cm ²
Used in Example 1 except that a total dose of 12 J / cm ² is applied.
In the same manner as in No. 8, a pattern was drawn on the film and metallized.
A high-resolution pattern having a line width of 0.5 μ was formed.

This result shows that the dose required for writing the pattern of UTF3 has nothing to do with the substrate.

Example 20 Formation of High Resolution Metal Pattern on Polysilicon Using Commercially Available ArF Laser / Alignment System Twelve p-type silicon wafers were provided with a 30 nm thick thermally grown silicon dioxide layer (gate oxide layer) and Film thickness 350n
m n-type top layers were sequentially deposited and cleaned by standard methods. Wafers 1-6 were treated with UTF1 as in Example 1, and wafers 7-12 were treated with UTF3 as in Example 9. Draw a pattern on the wafer one week after film formation,
Stored in polypropylene wafer carrier. SUSS
MA 56 5-inch type (5-inch product
The wafer was exposed with an ArF laser through a fused silica mask for NMOS transistors bonded to a mask aligner. All irradiations were performed with a pulse intensity of about 0.27 mJ / cm ² and a pulse repetition rate of 150 H.
z. The total dose was 8-20 J / cm ² , and it took 200-500 seconds to complete the exposure. The contact pressure is 900 g / wafer to 50 from hard close contact.
Various values were used up to a soft contact of 0 g / wafer. The wafer was metallized by standard copper plating. When utilizing intimate contact, the pattern present on the mask was almost completely replicated (> 90%) on the wafer, but significant amounts of metal were deposited on other areas of the wafer. It is presumed that the cause is the destructive (harmful) interference reflection inherent in the monochromatic collimated light source. High resolution (sub-micron), although soft contact to the mask suppresses or prevents metal deposition in unwanted areas
Lines are not reproduced well.

The results show that commercial source / alignment systems can be used to form high resolution metal patterns on semiconductor substrates. Also, although UTF1 and UTF3 are different in the type of reactive group at the non-polar end of the molecule, they can both be used for the drawing of metal patterns and show that the two films have the same dose range. . The energy required to form patterns in these film resists is on the order of 10 J / cm ² , which is the value required for conventional thick film photoresists, ie, about 10-1.
It is considerably higher than 00 mJ / cm ² . As a result,
For a given energy dose, the time required to pattern the UTF film is significantly extended. However, a new ArF laser projection system has been developed that can deliver pulses with a pulse intensity of 1.0 J / cm ^{2 at} a repetition rate of 150 Hz (DJ Ehrlich, JY Tsao &
C. O. Bozler, Journal of Va
cumum Science and Technology
gy B, vol. 3, p1, 1985). The total time to pattern a UTF film with the system would be about 0.07 seconds. This value is 60 wafers /
It is shorter than the exposure time guideline required for VHSIC production lines, which gives time throughput, ie 1.0 seconds.

Example 21 Formation of NMOS Transistor Test Structure Using Commercially Available ArF Laser / Alignment System Wafer 6 with a copper pattern of transistor test structure formed as described in Example 20 was treated with Freon 115 (150 mTorr). Was used in a Plasma Therm 500 Reactive Ion Etcher (RIE) using a plate power of 150 W at a flow rate of 50 cc / min. As a result, the film thickness is 350n excluding the region protected by the overlying copper layer.
m of the polysilicon layer was removed. The wafer was immersed in 18 molar nitric acid for 2 minutes to remove copper, and washed with distilled water. Model 30 operating at an energy of 75 KeV
The wafer was doped with phosphorus at a dose of 2 × 10 ¹⁵ ions / cm ² with a 0 kV excelator ion implanter to form a source and a drain. After ion implantation (to remove the thermally grown gate oxide layer), the wafer is cleaned for 40 seconds in an RCA ™ cleaning process with a buffered hydrofluoric acid etchant, then at 900 ° C. under a nitrogen atmosphere. Heated.

The electrical properties of the single-level transistor test structure were evaluated by the two-point probe method using two micromanipulators in combination with a Tetronic model 576 curve tracer. No discontinuity was observed in all lines tested. Width 10μ, 5
The current-voltage response of the gate structures of μ and 1 μ was measured to predict the behavior of the working transistor. When the wafer was observed by SEM, a 0.5μ continuous polysilicon gate with vertical edges was observed and no pinholes were present.

The results show that the copper resist after etching can be removed and the replication of the mask structure in the etched substrate is very accurate. We also show that reactive ion etching with Freon 115 ™ can be used to transfer a metal pattern with sharp edges to the substrate as compared to conventional organic photoresists. In this example, since the silane film is provided on the substrate wafer one week before the pattern formation,
It shows that the silane film is extremely stable. Finally, this example shows that high resolution working transistor test structures can be manufactured using the novel method of the present invention. It also demonstrates that other important components of integrated circuits such as interconnect leads, biases, contacts and capacitors can be made using the method of the present invention.

Example 22 Formation of Negative Image of Metal Pattern An n-type silicon wafer having a CVD oxide layer with a thickness of ½ μ was cleaned and then pure 1,1,1,3,3,3-hexamethyl. It was treated with disilazane (UTF4) for 20 minutes (contact angle = 79 °). The wafer is then heated at 100 ° C for 3
Cure for minutes. The reaction of the substrate with UTF4 produced a surface of trimethylsilyl groups, with the simultaneous release of ammonia. The film was patterned with a low resolution mask and Hg / Ar lamp and exposed for 30 minutes. The contact angle was unchanged in the non-irradiated area but decreased to 0 ° in the irradiated area. The patterned wafer was then treated with UTF3 as described in Example 9 to increase the contact angle of the previously irradiated area from 0 ° to 64 °. The wafer was then metallized by standard copper plating. The metal pattern was formed only in the irradiated area of the wafer. That is, a negative image was obtained by development.

This is the first example of the method of the invention used for negative imaging. This result indicates that the irradiation of UTF4 creates a region in the substrate to which the second silanizing reagent can be bound. The presence of hydroxyl groups is required for the surface reaction, so that the irradiation is performed with Si--O or S.
It can be considered that the i-C bond cleaves the initial monolayer from the surface, exposing the uncovered areas of the substrate. Thus, in the illuminated area some chemical reaction involving hydroxyl groups (eg silanization) may occur. The results also show that UTF4 is effective as a reagent to prevent metal deposition in selected areas.

Example 23 Fabrication of Metal Patterns Using a Two-Step Surface Activation System An n-type silicon wafer with about 1 / 2μ of CVD oxide layer is cleaned and then UTF3 as described in Example 9.
Processed in. Draw a pattern on the film with a low resolution mask,
It was exposed with an Hg / Ar lamp for 30 minutes. Next, 0.5M
The wafer with a solution containing 10 g / l of SnCl ₂ in HCl of 3 min, washed 3 times with distilled water,
Then 0.05 M containing 0.25 g / L PdCl ₂ .
Of HCI solution for 3 minutes and rinsed again. The wafer was then metallized using a standard copper plating bath, forming a very smooth copper film in the non-irradiated areas of the film. When observed by optical reflection microscopy, the plated film was smoother than the copper coating formed using the commercial catalytic Pd / Sn activator described in the previous examples.

The results show that the two-step tin and palladium activator system can be used to produce improved copper coatings. Further, the order of using tin and palladium may be exchanged.

Example 24 Formation of MOS Capacitor Test Structure An n-type silicon wafer having a thermal oxide layer with a film thickness of 100 nm was washed and treated with UTF3 as in Example 14. A pattern was drawn on the film using a mask having a standard type capacitor test structure and irradiated with a Hg / Ar lamp for 28 minutes. The wafer was metallized by the standard copper plating method used in Example 5, and a square metal pad with 800 μm on a side (area =
6 × 10 ⁻³ cm ² ) was formed. Fully automatic Micromanipulator C for metal pad and backside of wafer
By probing with a -V measuring system
The properties of thermal oxide / n-type silicon (MOS) capacitors were tested. The capacitance was found to be 26 pF / cm ² with minimal (10 mV) hysteresis and was stable at room temperature for over 3 weeks. This shows that the problem of element deterioration due to metal contamination (diffusion of copper into thermal oxide) does not occur in the place shielded by the mask.

This is an example of a functional metal / dielectric / semiconductor capacitor made by the novel method of the present invention.

Example 25 Experimental Step-Coating on Polysilicon A series of parallel C's with a width of 10 or 20 μ and a thickness of 400 nm.
A 400 nm-thickness of p-type polysilicon was deposited on an n-type silicon wafer previously provided with a VD oxide wire as a cover layer. The wafer was then washed and treated with UTF3 as described in Example 9 to form a film. 9 for CVD oxide lines
Hg / Ar through the same parallel line mask oriented at 0 °
The film was patterned by illuminating the lamp for 28 minutes. The film was metallized by standard copper plating. The resulting copper wire was a continuous wire of uniform thickness and accurately followed the contours of the polysilicon steps.

The results show that excellent step coverage is obtained which is important for the fabrication of gate and interconnect leads in the non-planar regions of the wafer.

Example 26 Formation of Metal Pattern on Platinum Platinum foil was washed by heating with a propane torch until it became incandescent. The contact angle of the clean foil was 0 °. The foil was then treated with UTF3 and a pattern drawn with low resolution lines as described in Example 9. The contact angle in the non-irradiated area was 73 °. The contact angle of the irradiation area was 0 °. The patterned film was metallized by standard copper plating. A metal pattern was formed only in the areas shielded by the mask and this pattern showed excellent adhesion to the substrate in the Scotch tape test as described in Example 11.

The results show that the metal pattern was formed on the metal substrate having the thin surface oxide layer.

Example 27 Formation of High Resolution Pattern on Si ₃ N ₄ Coated GaAs Substrate A gallium arsenide compound substrate was coated with a 100 nm thick silicon nitride layer using plasma deposition. The contact angle of the plasma nitride layer was 0 °. Wafer to UTF3
(Contact angle = 73 °), a pattern was drawn using a mask, and metallized as described in Example 12. A continuous metal line was provided on the substrate that replicated the lines of the mask.

This shows that the plasma nitride / GaAs combination can be used as a substrate for forming high resolution metal patterns on semiconductors other than silicon.

Example 28 Selective Metallization of Trichloro (4-pyridyl) -ethylsilane An ultrathin film of this material was formed on a clean glass slide using the standard method described for the other silane materials. The contact angle was about 40 °. The film was exposed through a mask with a mercury / argon pen lamp that passed a 7-43 bandpass filter (Corinig Glass Corp.). This filter only passes the wavelengths from 235 nm to 415 nm and not any other wavelengths of the pen lamp such as 195 nm and 185 nm which are known to participate in the photochemical reactions of the membrane.

The nominal irradiation time without the filter is 30 minutes, but here the membrane was irradiated for 90 minutes.
For additional time, the filter will reduce the incident light at 254 nm to approximately 3
It is a value calculated based on passing only 5%.
This wavelength is estimated to be an important wavelength for forming a precise photochemical pattern by the pyridinyl film.

After the irradiation, Shipley Co. The film was treated by the standard plating method using the above chemicals. The formation of metal patterns was observed in the masked areas of the film-coated substrate. This is because components such as pyridinyl groups that absorb light at longer wavelengths than isolated olefins are present in the film,
It shows that the film is sensitive to light of longer wavelengths as described above. Thus, for precision patterning, commercial sources (eg, krypton fluoride (248n) excimer laser steppers or conventional mercury lamps) may be used rather than argon fluoride (193 nm) laser steppers. The pattern obtained at the doses used here indicates that the sensitivity of the film is at least comparable to that of the other silanes (because the total doses used are equal).

Example 29 Polysulfone board (Victrex PES3601 MG20, Victrex PES3601 MG20, with pattern irradiation from a mercury / argon pen lamp through a filter, was conducted in the same manner as in Example 28 above.
LNP Plastics Co. ) Was exposed. The exposure time was 90 minutes. The board was selectively metallized with a Shipley copper plating bath. The aromatic groups in the polysulfone resin can absorb radiation at 254 nm. The irradiation source is the same as in Example 28.

Example 30 A clean silicon thermal oxide wafer was placed in a scanning electron microscope equipped with the appropriate attachments for high resolution patterning. An electron beam was rastered onto the surface of the wafer to form lines of various widths. After irradiation, the wafer was removed from the SEM and selectively metallized in a Shipley plating bath. Copper metal was selectively deposited only on the areas of the wafer that were exposed to the electron beam. This corresponds to negative imaging and is a very advantageous feature of electron beam lithography since the pattern is usually formed on only a small portion of the wafer surface. There is an advantage of irradiating only the area where the pattern is to be formed, without irradiating other portions. According to this method, a fine metal line having a width of 0.1 μm is formed.

Metallization is obtained after exposing the wafer with an electron beam to a wide range of doses, up to several hundred millicoulombs per cm ² . Better results (more clear pattern) at a relatively low dose of 70 mC / cm ^2.
Is considered to be obtained. The resolution obtained in this experiment is estimated to be limited by the size of the electron beam. 10 using a higher resolution electron beam with a narrower beam width or lower energy (eg 15V)
It would be possible to obtain linewidths below 0 nm. Another irradiation source is the scanning tunneling microscope, which has been found to be useful as an irradiation tool for electron beam lithography with a 10 nm line width regime (M
cCord & Peas, J.C. Vac. Sci.
Tech. B, p86, 1986).

Example 31 This example shows a bimetallic pattern (high phosphorus Ni / Cu, low phosphorus Ni / Cu).

The p-type silicon wafer was treated with UTF1 as in Example 1 and divided into two halves. The two wafers were illuminated with a Hg / Ar pen lamp through the mask for 30 minutes. Wafer the MacDermid XD2408
-T, treated with Pd / Sn colloid for 5 minutes and then washed with water. Next, one of the wafers is replaced with MacDermic (W
Atterbury, CT) was placed in a high phosphorus nickel plating bath (J67 / J28F) and held for 4 minutes. Add the remaining half to a low phosphorus content nickel plating solution (MacDermid J60 / J61) and
Hold for minutes. The pattern grew on both wafers with a high resolution of a line size of 1μ. Then both wafers were placed in a copper plating bath. The initially silver pattern is 2
It turned completely copper in minutes. The results show that high resolution patterns can be obtained from both low-P (magnetic) nickel and high-P (non-magnetic) nickel. It also shows that the patterned metal layer can act as a substrate for the subsequent deposition of another material, such as metal, without compromising resolution.

Example 32 Selective metallization of silane films with aromatic groups directly bonded to silicon atoms is possible. An ultra thin film of silane having an aromatic group directly bonded to a silicon atom,
It was formed on a clean polysilicon surface using standard methods described for other silane materials. The silanes used were; chlorotriphenylsilane (CTP), diphenylvinylchlorosilane (DPVC) and p-chloromethylphenyltrichlorosilane (CMPTC). Using the output of a mercury / xenon 500 W lamp, a film-coated substrate is subjected to Karl Suss Model MJB3.
It was exposed through a mask from a UV contact aligner. The radiation that reaches the substrate from this source is 220 nm
It was only light with a longer wavelength.

The film was irradiated for 30 minutes with the lamp power adjusted to 7 mW / cm ² at 254 nm. Then Shipl
ey Co. The wafers were processed by standard plating methods using the chemicals of. A thin (eg, 50 nm thick) continuous metal pattern was preferentially grown in the masked area of the film-coated substrate. In the case of CMPTC and CTP silane,
Virtually no plating was observed in the areas not masked.

As in Example 28, the membrane has a moiety such as a phenyl group capable of absorbing light at a longer wavelength than a group such as an isolated olefin. Become photosensitive. However, in the case of CMPTC and CTP silane, the contrast between the plated and unplated areas is improved, unlike the weak contrast observed with the ethylipyridinylsilane and DPVC used in Example 28. , Which indicates that the position of the aromatic group in the molecule is important.

It can be easily inferred that the reason why the contrast is improved is that the chromophore absorbs light into the film, and photolytic cleavage of the molecule occurs at or near the chromophoric group. When using low-energy radiation for patterning, for example radiation with wavelengths longer than 220 nm,
Chromophores such as phenyl or pyridine rings are excited, but chromophores that do not absorb such long wavelengths are not excited. A film having a chromophore that is sensitive to this radiation at a position remote from the silicon atom undergoes photolytic cleavage only at that position, binding organic moieties such as methyl, vinyl and methylene groups to the silicon atom. Therefore, the pattern of the initial film in the masked area is mixed with the partially cleaved film in the exposed area. This occurs in the case of DPVC membranes where the phenyl ring is cleaved and the vinyl groups are retained. The partially cleaved molecules adhere well to the Pd / Sn colloid to plate the exposed areas, but at a lower quality and coverage than the unexposed areas. When using a film in which only aromatic groups are directly attached to the silicon atom, photolytic cleavage completely removes the organic portion of the molecule at the silicon atom. As a result of this, the same conditions as when using irradiation rays shorter than 200 nm are obtained. The reason is that most organic components absorb radiation below 200 nm and are therefore cleaved.

Example 33 Selective metal plating of p-chloromethylphenyltrichlorosilane can be performed using a KrF excimer laser as an exposure tool.

The wafer was CMPTed as in Example 32.
Treated with C silane and passed through a quartz mask to KrF (248
nm) Lamda Physik excimer laser. Laser pulse intensity is about 400 mJ / cm
² and the wafer was irradiated at a pulse repetition rate of 4 Hz for 5 to 7 seconds. The total dose given to the wafer is 8.5 J /
cm ² and 11.9 J / cm ² .

Next, Shipley Co. The wafer was processed by the standard plating method using chemicals manufactured by the company. A thin continuous metal pattern with submicron lines was preferentially grown on the masked areas of the film-coated substrate, with virtually no plating observed on the areas not masked.

Example 34 Selective metallization can be performed on a silane film having an aromatic group bonded to a silicon atom via a spacer group. Ultra thin films of silane with aromatic groups attached to silicon atoms through spacer groups were formed on clean polysilicon surfaces using the standard procedure described for the other silane materials. The silane used was (Petrarch
Co. , Bristol, PA) trichloro- (4-pyridyl) ethylsilane (pyridylsilane) and 7- [3- (chlorodimethylsilyl) propoxyl] -4-methylcoumarin (coumarinsilane). The film-coated substrate was exposed through a mask from a mercury / argon lamp in the same manner as in Example 3. The membrane was irradiated for 30 minutes. Then, Shipley Co. The wafers were processed by standard plating methods using chemicals from the manufacturer. A thin (about 50 nm thick) continuous metal pattern was grown only on the masked areas of the film coated substrate.

Although the treatment of the present invention has not been theoretically elucidated, it is presumed that the radiation acts to remove at least the organic groups present on the surface of the organic substrate. For example, in Example 10, the infrared spectrum of the silane monolayer film after irradiation with vacuum ultraviolet light showed that organic groups (eg methyl groups, octenyl groups) could no longer be detected. Si-C and / or Si-O- (surface) bonds and possibly C-
It is presumed that the photolytic cleavage of the C-bond removes at least organic groups from the membrane in the illuminated area. The irradiation removes the organic portion from the silane film, but it is believed that a considerable amount of silicon derived from the silane deposition layer remains on the surface after irradiation. The reasoning is that photolytic cleavage occurs preferentially at Si—C and C—C bonds over Si—O bonds, and at least a partial atomic layer of silicon oxide remains after irradiation. it can. Due to the known reactivity of freshly cleaved or sputtered Si, the photolysis products are susceptible to react rapidly in ambient atmosphere to produce surface Si-OH and / or Si-O groups. Silicon oxide has atomic resolution in the Z direction and submicron resolution in the XY directions (X and Y are in the plane of the film, Z is perpendicular to the substrate).
It can be shown that it can be selectively deposited with. It is expected that the molecular assembly of silicon oxide can be deposited in a pattern by sequentially performing the film deposition and photolytic cleavage steps. Therefore, a semiconductor microcircuit on a silicon substrate can be manufactured by a bottom-up method without requiring any etching step. Similarly, applying the treatment mechanism of silane film to titanate, zirconate and aluminate,
It is possible to selectively deposit a molecular assembly consisting of titanium oxide, zirconium oxide, aluminum oxide and related surface-reactive substances or combinations thereof.

The metal layer is a preferred material used for pattern formation and deposition in a printed circuit or the like, but the material of the layer provided on the substrate is any of an inorganic material, an organic material, a semiconductor material, a metal or a combination thereof. Good. For example, when silane is used for the organic substrate, it is preferable to separately adhere the layer of the radiation-reactive substance to the substrate, but in some cases, the surface of the substrate itself is irradiated. May be considered to be a layer.

The self-assembled monolayer is preferably chemically adsorbed on the surface of the substrate having functional groups, although in some cases the film is formed from a portion of the outer surface of the substrate. Alternatively, it may be considered to be a part of the outer surface of the substrate. Therefore, when the substrate contains a chromophore, the chromophore is a substance that absorbs the exposure wavelength and changes the reactivity to the electroless plating bath from metal plating receptivity to metal plating non-receptivity or vice versa. The substrate can be used directly without the need for the formation of additional monolayers. In all cases, the outer layer of the substrate (which may be considered to be the monolayer portion of the substrate) or the monolayer provided on the substrate is a metal plating receptive or non-receptive surface by electroless plating. Have.
The radiation causes the receptive surface to become non-receptive, or vice versa. Then
A catalyst for accelerating plating is used to deposit metal in a predetermined region or prevent deposition of metal in a predetermined region by an electroless plating method. When writing a mask or pattern with radiation before metal deposition, the metal may only adhere to certain areas and the metal itself may act as a mask for the subsequent stages. The metal layer may be an etch resistant resist, or in the case of printed circuit boards, masks and microwave circuits the metal layer may be the final product. Therefore, it is possible to manufacture the product in a manner such that the deposited metal layer is deposited only where it is needed for end use and no metal removal is required.

Although particular monolayer films have been described and specific silanes have been described, other films may be provided on the surface and various other silanes such as tridecafluoro-1,1,2,2. -Tetrahydrooctyl-1-
It is also possible to use perfluorinated silanes such as dimethylchlorosilane, octadecyldimethylchlorosilane, trifunctional silanes such as trichlorooctenylsilane, trimethoxyoctenylsilane, trimethoxy-4-aminobutylsilane.

Other materials which are radiation-sensitive and can act as chromophores and which can adhere to the substrate can also be used. An example is a titanate having the general formula Ti (OR) ₄ . All four ORs in the formula may be the same group or different groups. Like these silanes, these substances and related zirconate and aluminate molecules spontaneously react with surface hydroxyl groups to form organic monolayers covalently bonded to the substrate, simultaneously generating alcohols. . An O-Ti bond is formed between the surface hydroxyl and the titanate. Examples of titanates that can be used to form the selective metal pattern are 2-propanolato-tris (phosphate-O-dioctyl) titanium (IV), UTF.
12; methoxydiglycolylate-tris-O- (2-
Propenoart) -Titanium (IV), (UTF3
9); 2-propanolato-tris (3,6-diazahexanolate) titanium (IV), (UTF44). Other single layer film forming materials such as Langmuir
Blodgett films, thiol or disulfide films assembling on gold surfaces, carboxyls or acid chlorides can also be used.

The thickness of the deposited metal layer may be a value known in the art of manufacturing electric products by electroless plating.
The thickness of the continuous film having the desired resolution is 20 nm.
The resolution is, for example, a metal line width of 0.5μ and a wiring interval of 0.5μ.
And high energy short wavelength radiation, eg 20
When an irradiation line of 0 nm is used, the metal line width is 0.2 μ and the wiring interval is 0.2 μ.

In addition to the above-mentioned substrate, since the outer layer contains a chromophore, it is possible to use a substrate which can directly form a pattern without using an additional monomolecular film. These substrates may be organic or inorganic materials with a chromophore of the appropriate wavelength on top. Examples of such substrate materials are shown below. It also indicates whether the image of the metal deposited after irradiation is negative or positive. The positive image is the metal deposited only on the non-irradiated areas of the substrate after the catalyst deposition, and the negative image is the metal deposited only on the irradiated areas of the substrate after the catalyst deposition.

Polyethylene-negative paraffin-negative polypropylene-positive polyethylene terephthalate (Mylar) -positive polyether polyurethane-positive polyisoprene (natural rubber) -positive polysulfone-positive polymethylmethacrylate (Plexiglas) -positive polyacrylic acid-positive poly ( (Cis-1,4-butadiene) -negative polyurethane-positive RTV silicone rubber-positive polyethersulfone-positive Various modifications which do not depart from the essential requirements of the invention will occur to those skilled in the field of semiconductor manufacturing, printed circuit manufacturing or thin film chemistry. Would be obvious. It will also be appreciated that the invention is not limited to the procedures described herein and the materials used in the procedures. The scope of the present invention described in the claims is
It also includes obvious equivalent changes and substitutions of materials known to have equivalent properties.

[Brief description of drawings]

FIG. 1A is a schematic diagram showing a process of chemisorbing molecules from a homogeneous solution on the surface of a solid substrate to form a monomolecular film on the solid substrate. B is a schematic definition of the symbols used in the figures.

FIG. 2 is a schematic diagram showing pattern irradiation applied to a monolayer film to change the reactivity of a given region of the monolayer.

FIG. 3A is a schematic view showing a state in which a colloidal catalyst precursor is attached to residual reactive groups of silane molecules to form a metal plating layer on a monolayer film. B is a schematic diagram showing an unreacted silane monolayer and unreacted irradiation by-products.

FIG. 4A is a schematic view showing a cross-sectional state of a semiconductor substrate after ion etching and a metal film on a plateau formed by etching the substrate. B is a schematic diagram showing a monolayer formed on the irradiation by-product by chemisorption of colloid-philic molecules from a homogeneous solution.

FIG. 5A is a schematic showing removal of metal / colloid catalyst after etching. B is a schematic view showing a state in which the colloidal catalyst precursor is attached to the colloid-philic molecules to form a metal plating layer on the monolayer film.

[Explanation of symbols]

1 Solid substrate 2 heads 3 Reactive part 4 Non-reactive part 5 spacers 6 Colloidal catalyst 7 metal pattern

Front Page Continuation (72) Inventor Martin Sea Petzcolor Merriland 20904, United States, Silva Spring, Batuscania Road 12917 (72) Inventor Jeffrey M. Calvert United States, Virginia 22015, Burke, Wilmington Drive 6033 (72) Inventor Jacques H. Yoyoja Junia United States, Virginia 22153, Springfield, Great Lake Road 8409 (72) Inventor Cristay Earl Kay Marian United States, Virginia 22307, Arizandria, Kenyon Drive 6805 (56) Reference JP-A-1-65776 (JP, A) JP-A-2-90679 (JP, A) JP-A-1-180984 (JP, A ) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/28-21/288 H01L 21/3205-21/3213 H01L 21/768

Claims (22)

(57) [Claims] 1. To form a conductive path on a substrate having a polar functional group on its surface, (a) a self-assembled monolayer is chemically adsorbed on the surface of the substrate, and (b) a predetermined pattern is formed on the film. To modify the reactivity of the membrane region, and (c) deposit the catalyst precursor only on the membrane region having sufficient reactivity to bond with the catalyst precursor, and (d) attach the substrate to an electroless metal. A method comprising placing in a plating bath and metal plating the area where the catalyst precursor is attached. 2. The substrate is a semiconductor substrate, and the self-assembled monolayer has the formula: RnSiXm [wherein R is an organic functional group; n = 1, 2 or 3; m = 4-n; and X is The group according to claim 1, which is a group selected from the group consisting of halogen, alkoxy, and amine. 3. The method of claim 1, wherein the substrate is a semiconductor silicon solid and the self-assembled monolayer is formed on the solid by adsorption from a chlorosilane-containing solution. 4. The chlorosilane in the solution is 7-octenyldimethylchlorosilane.
The method described in. 5. The chlorosilane in the solution is 5-hexenyldimethylchlorosilane.
The method described in. 6. The method according to claim 2, wherein the catalyst precursor is a colloid containing palladium and tin. 7. The method of claim 6, wherein the substrate is sequentially treated with a tin and palladium compound to produce a catalyst precursor. 8. The method according to claim 1, characterized in that the reactivity of the region of the membrane is modified by irradiating with a radiation beam which promotes the photolytic cleavage of the irradiated region. 9. The method of claim 8 wherein the wafer is maintained in a vacuum or inert atmosphere during the irradiation process. 10. The method according to claim 9, wherein the irradiation rays are ultraviolet rays having a wavelength of less than 200 nm. 11. The method of claim 10, wherein the self-assembling film is a silane layer. 12. The substrate is a semiconductor silicon substrate having a hydroxyl group on its surface, and the self-assembled monolayer is
The method of claim 1, wherein the method is bound to the substrate by a siloxane bridge to the hydroxyl groups. 13. In order to form a metal path on a substrate, a monomolecular film forming the surface of the substrate is selected, and the reactivity of the region of the film is modified by irradiation so as to draw a predetermined pattern on the film, A method characterized in that a catalytic reaction is caused only in a region of a film that requires sufficient reactivity with respect to a predetermined catalyst, the substrate is placed in an electroless metal plating bath, and the catalytically reacted region is metal-plated. 14. The substrate is a dielectric silicon oxide,
The method of claim 13, wherein the film is formed on the substrate by adsorption from a chlorosilane-containing solution. 15. The method of claim 1, wherein the substrate is alumina and the film is formed from chlorosilane. 16. The method according to claim 1, wherein the substrate is a conductive metal and the film is formed by adsorption from chlorosilane. 17. The method according to claim 15, wherein the chlorosilane is UTF1. 18. The substrate is selected from semiconductor silicon, dielectric silicon oxide, alumina, metal and quartz,
The method of claim 1, wherein the membrane is adsorbed from a silane-containing solution. 19. The method of claim 18, wherein the silane is 4-aminobutyldimethylmethoxysilane. 20. The substrate is selected from the group consisting of semiconductor silicon, dielectric silicon, alumina, metal and quartz, the monolayer is adsorbed from a solution of silane or titanate, and the catalyst precursor is palladium and A tin-containing colloid, the metal plating being selected from the group consisting of metals that can be deposited by electroless plating, i.e., copper, gold, cobalt, nickel, permalloy (iron-nickel-boron alloy) and palladium; The method of claim 1, wherein the substrate is placed during reactive ion etching to transfer the pattern to the substrate and then the metal is removed by an oxidizing acid. 21. The method according to claim 1, wherein the metal plating consists of two layers of different metals. 22. The method according to claim 1, wherein the substrate includes a second substance overlying the monolayer.
The method according to 3.