JPH08148339A - Electronic component and magnetic component - Google Patents

Abstract

PURPOSE: To enhance process control of multilayer conductor wiring employing Cu as main conductor while simplifying the process, and to put electronic and magnetic components thus obtained to practical use while reducing the cost. CONSTITUTION: An underlying conductor 2 is patterned specifically on the surface of an insulator 1 and a main conductor 3 of Cu is patterned specifically thereon. A first coating conductor 4 composed of at least one kind of Ti, Ta, Mo, Nb or Ni and a second coating conductor 5 composed of at least one kind of Au or At are laminated sequentially, as conductor wirings, on the surface of the main conductor facing the insulator thus producing an electronic device and a magnetic device having a planar coil made of the conductor wiring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component having a laminated conductor wiring having Cu as a main conductor, and a magnetic component having a coil formed by using the laminated conductor wiring.

[0002]

2. Description of the Related Art In recent years, miniaturization and weight reduction of various electric devices have been rapidly progressed, and electronic parts constituting the devices are strongly required to be small, thin and lightweight. In order to meet this demand, the adoption of surface mount devices (SMD) has become mainstream. Furthermore, a multi-chip module (MCM) in which a plurality of bare chips are mounted on a multilayer wiring board is under study in order to integrate SMDs with high density.

In the above-mentioned multilayer wiring board, both the wiring resistance and the dielectric constant of the insulator around the wiring are required to be small in order to reduce the signal delay. From this viewpoint, Cu is used as the wiring conductor material, and SiO ₂ or polyimide is used as the surrounding insulator material. Here, if the structure is such that Cu and the surrounding insulator are in direct contact with each other, Cu diffuses in SiO ₂ or reacts with polyamic acid which is a precursor of polyimide, thereby deteriorating the dielectric strength of the surrounding insulator. Not only that, but it may also cause an increase in wiring resistance. Therefore, conventionally, it is general to form a multilayer wiring so as not to directly contact Cu with an insulator. For example, when SiO ₂ is used as the insulator, Cu is coated with Ti, TiN or the like to suppress the diffusion of Cu. When polyimide is used as the insulator,
Cu is coated with Ni, Ti or the like in order to suppress the reaction between the precursor solution and Cu.

Here, an example of a conventional method for manufacturing a multilayer wiring board using Cu as a main conductor and polyimide as an insulator will be described. (A) First, on an insulating substrate such as alumina,
0.1 μm as a base conductor with good adhesion to the substrate
Ti of about 1 μm and Cu of about 1 μm, which is used as a conductor for a plating electrode and becomes a part of the main conductor, are sequentially formed by a method such as a vacuum deposition method. A thick film resist is applied on the entire surface and patterned by photolithography to form an opening in a portion where a wiring is formed. (B) Next, Cu serving as a main conductor is grown to a predetermined thickness by electroplating in the opening portion of the resist, and then the resist is peeled off. To cover the exposed surface of Cu, Ti is deposited by a method such as vacuum deposition as a coated conductor for suppressing the reaction with the polyimide precursor. (C) Next, after patterning a resist for removing the laminated conductor (Ti / Cu / Ti) in the space portion by photolithography, using this as a mask, an etchant mainly containing acetic acid, nitric acid, and hydrofluoric acid is used to form Ti.
Are alternately etched with Cu by an etchant composed of ferric chloride and water. (D) Next, a polyimide serving as an insulator is formed on the entire surface, and contact holes are formed. (E) Further, the steps (a) to (d) are repeated to form a multilayer wiring. Finally, after making a pad hole, Ni of 1 μm or more and Au of 1 μm or more to be a pad conductor are sequentially formed by a method such as vacuum deposition, and a resist (not shown) is patterned by photolithography, which is used as a mask. A other than the pad
u and Ni are removed to form a pad conductor.

However, the above-mentioned prior art has the following problems. (1) It is difficult to reliably control the Ti / Cu / Ti alternating etching in the step (c).
Since the Ti is hardly etched during the etching of Cu, side etching of Cu cannot be avoided. As a result, an overhang of Ti occurs as shown in FIG. If an overhang occurs at the bottom of the conductor,
When the polyimide precursor, which is an insulator, is applied in a later step, bubbles are likely to be involved. In this way, when the multi-layer wiring board contains bubbles, various problems occur.

(2) Since it is necessary to separately deposit a metal such as Ni and Au on the pad portion for patterning,
The process becomes complicated. It may be considered that the problem (2) can be solved by coating the main conductor made of Cu with Al or an Al alloy, as described in JP-A-60-128641. However, Al or an Al alloy that coats Cu easily induces stress migration, thermal migration, electromigration, or the like to cause hillocks. The generation of such hillocks often causes voids, and Cu in the exposed portion may react with the insulator.

Further, a coil formed by processing a conductive material is used for a flat type inductor, a transformer, or a thin film magnetic head. In this case as well, Cu having a high electric conductivity is used for reducing the coil resistance. Often. Conventionally, in these magnetic components, a resist is often used as a gap between coil lines and as an insulator above it (amorphous electronic device research laboratory, April 1994, research report). This is because if polyimide or SiO ₂ is used as an insulator instead of a resist, the same problems as in the case of the above-mentioned multilayer wiring board, that is, the difficulty of process control and the complication of steps occur. For example, Japanese Patent Laid-Open No. 1-277311 discloses a thin film magnetic head having a conductor in which Cu is coated with Ni, but the above problem cannot be avoided. However, when a resist is used as the insulator, its heat resistance is inferior and the process temperature must be lowered. Particularly, in order to impart magnetic anisotropy to the magnetic material, annealing is performed in a magnetic field, but the upper limit temperature is limited to the heat resistant temperature of the resist (about 200 ° C.). Therefore, the magnetic anisotropy dispersion cannot be sufficiently reduced, which causes a problem that the frequency characteristic is deteriorated.

[0008]

As described above, an electronic component such as a multilayer wiring board including a laminated conductor wiring having Cu as a main conductor, and an inductor including a planar type air-core coil obtained by processing such a laminated conductor wiring. , Magnetic components typified by transformers and magnetic heads have problems such as difficulty in process management and complicated processes. Further, since the process cost rises due to these problems, the commercialization of electronic components and magnetic components has been delayed, and it has not yet been possible to stimulate large-scale industrial demand.

An object of the present invention is to improve the process control of a laminated conductor wiring having Cu as a main conductor and to simplify the process, and to use it in electronic parts such as a multilayer wiring board, an inductor, a transformer, and a magnetic head. It is to achieve the practical use and cost reduction of a typical magnetic component.

[0010]

An electronic component according to the present invention has a conductor wiring covered with a base insulator and a surrounding insulator,
The conductor wiring is a base conductor made of at least one selected from the group consisting of Ti, Ta, Mo, Cr, Nb, and W processed in a predetermined pattern on the surface of the base insulator, and a predetermined conductor on the base conductor. The main conductor made of Cu processed into the pattern of T and the main conductor made of Cu, which is formed by sequentially stacking so as to cover the surface of the main conductor facing the peripheral insulator.
i, Ta, Mo, Nb, a first coated conductor made of at least one selected from the group consisting of Ni, and Au,
And a second coated conductor made of at least one selected from the group consisting of Al. The magnetic component of the present invention has a coil formed by using the laminated conductor wiring having the above configuration.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows a laminated conductor wiring according to the present invention. As shown in this figure, a base conductor 2 processed into a predetermined pattern and a main conductor 3 made of Cu are formed on a base insulator 1. The surface of the main conductor 3 made of Cu facing the surrounding insulator is covered with the first covered conductor 4 and the second covered conductor 5. A peripheral insulator 6 made of polyimide or SiO ₂ is provided around the laminated conductor wiring having such a structure. Furthermore, a contact hole is provided in the insulator 6, and a bonding wire 10 made of Au or Al is connected to the second coated conductor 5.

As described above, as the base conductor, Ti,
At least one metal or alloy selected from the group consisting of Ta, Mo, Cr, Nb and W, and the first coated conductor is at least one selected from the group consisting of Ti, Ta, Mo, Nb and Ni. And the second coated conductor is at least one metal or alloy selected from the group consisting of Au and Al.

The thickness of the base conductor 2 is preferably 0.05 μm or more, and the thickness of the first and second coated conductors 4, 5 is preferably 0.5 μm or more, more preferably 1 μm or more. This is because if the thickness of the base conductor 2 is too thin, adhesion failure due to diffusion of Cu or the like occurs, and the first and second coated conductors 4,
This is because if the thickness of 5 is too thin, sufficient mechanical strength may not be obtained when the bonding wire is connected to the pad portion. The upper limit of the film thickness of the base conductor 2, the first and second coated conductors 4 and 5 may be set so as to be thinner than the main conductor 3 made of Cu. It is 10 μm or less.

In the laminated conductor wiring according to the present invention, by selecting an appropriate metal species from the above-mentioned metal group as the base conductor 2, the first coated conductor 4 and the second coated conductor 5,
As shown in FIGS. 3A to 3C, although the shape of the conductor wiring differs depending on the manufacturing method, overhang does not occur in the lower portion of the conductor wiring.

Further, Cu, which is the main conductor, is used as an insulator between adjacent conductors or an interlayer insulator between multilayered conductors by the second and first coated conductors.
SiO ₂ because it is protected from O ₂ or polyimide
Diffusion into the interior and reaction with the polyimide precursor are suppressed.

Further, the first coated conductor inserted between the main conductor made of Cu and the second coated conductor made of Al, Au or Al-Au alloy is a refractory metal, which itself migrates. Hard to wake up. Therefore, Cu is not exposed due to the generation of hillocks and the generation of voids, and the reliability of the conductor wiring having Cu as the main conductor can be expected to be improved.

Further, since the first coated conductor disposed under the second coated conductor (Al and / or Au) is hard, a contact hole is exposed in the insulator 6 around the wiring. Even if the bonding wire made of Al or Au is directly wedge-bonded or ball-bonded by using the above-mentioned second coated conductor as a pad portion, sufficient mechanical strength can be maintained. For this reason, the step of depositing and patterning a metal on the pad portion as in the conventional case is unnecessary, and the step can be shortened.

In order to manufacture the laminated conductor wiring according to the present invention, the main conductor Cu, the base conductor (hereinafter referred to as metal A), the first coated conductor (hereinafter referred to as metal B) and the second coated conductor are used. (Hereinafter, referred to as metal C) may be formed by a method such as vacuum deposition or sputtering, or a thick film may be formed by an electroplating method using a Cu film, which is a main conductor only Cu previously formed, as an electrode. . A more specific manufacturing method will be described with reference to FIGS. 4A to 4E, 5A to 5E, and 6A to 6E.

In FIGS. 4A to 4E, the thickness of Cu, which is the main conductor, is set to 1 by using a method such as vacuum deposition or sputtering.
It is an example of a manufacturing process for forming a thin film having a thickness of less than 0 μm. First, a base conductor 2 is formed on an insulating substrate 1 by a method such as vacuum deposition or sputtering to enhance adhesion with the substrate.
As the metal A and Cu as the main conductor 3, Cu is formed, and a photoresist 21 is formed in a predetermined pattern thereon (FIG. 4A). Next, Cu and metal A are collectively etched with an etchant using the photoresist 21 as a mask (FIG. 4B). Subsequently, a metal B to be the first coated conductor 4 and a metal C to be the second coated conductor 5 are sequentially formed on the entire surface (FIG. 4C). Next, a photoresist 22 is formed into a predetermined pattern by photolithography so as to cover the main conductor line (FIG. 4).
(D)). Further, using the photoresist 22 as a mask, the metals C and B in the regions other than the main conductor lines are collectively etched by an etchant (FIG. 4E).

In this method, the metal A and the etchant 1 are so selected that the relationship of the etching rate R ₁ with respect to the etchant 1 used in the step of FIG. 4B satisfies the condition R _{1, Cu} ≧ R _{1, A} (1). Select. Further, the metals C, B and the etchant 2 are so set that the relation of the etching rate R ₂ with respect to the etchant 2 used in the step of FIG. 4E satisfies the condition of R _{2, C} ≧ R _{2, B} (2).
Select By selecting appropriate metal species and etchant in this way, the lower part of the wiring has a shape as shown in FIG. 3A, and no overhang occurs.

FIGS. 5A to 5E show an example of a manufacturing process in the case where the thickness of Cu which is the main conductor is formed into a thick film of 10 μm or more by using the electroplating method. First, the insulating substrate 1
A metal A as a base conductor 2 for enhancing the adhesion to the substrate and Cu as a plating electrode conductor 3a which is a part of the main conductor are formed on the top by a method such as vacuum deposition or sputtering, and a photoresist 23 is formed thereon. Are formed into a predetermined pattern (FIG. 5A). Next, by electroplating using a suitable plating solution, Cu which is the main conductor 3 is grown on the conductor 3a for the plating electrode exposed from the photoresist 23, and the photoresist 23 is removed (FIG. 5).
(B)). Subsequently, a metal B to be the first coated conductor 4 and a metal C to be the second coated conductor 5 are sequentially formed on the entire surface (FIG. 5C). Next, a photoresist 24 is formed in a predetermined pattern by photolithography so as to cover the main conductor line (FIG. 5D). Further, using the photoresist 24 as a mask, the metal C, B, Cu, and metal A in regions other than the main conductor line are collectively etched by an etchant (FIG. 5E).

In this method, the metals C, B, and C are set so that the relationship of the etching rate R with respect to the etchant used in the step of FIG. 5E satisfies the condition of R _C ≧ R _B ≧ R _Cu ≧ _RA (3). Select A and etchant. By selecting appropriate metal species and etchant in this way, the lower part of the wiring has a shape as shown in FIG. 3B, and no overhang occurs.

FIGS. 6A to 6E show another example of the manufacturing process using the electroplating method. First, the base conductor 2 is formed on the insulating substrate 1 by the same steps as those shown in FIGS.
Cu is formed as the metal A and a conductor 3a for a plating electrode which is a part of the main conductor, a photoresist is formed on the Cu in a predetermined pattern, and the main conductor 3 is formed by electroplating.
Cu is grown and the photoresist is removed. Next, a photoresist 25 is formed so as to cover the main conductor line.
Are formed into a predetermined pattern (FIG. 6A). Next, using the photoresist 25 as a mask, C by an etchant is used.
u and the metal A are collectively etched (FIG. 6B).
Subsequently, a metal B to be the first coated conductor 4 and a metal C to be the second coated conductor 5 are sequentially formed on the entire surface (FIG. 6).
(C)). Then, a photoresist 26 is formed in a predetermined pattern by photolithography so as to cover the main conductor lines (FIG. 6D). Further, using the photoresist 26 as a mask, the metals C and B in the regions other than the main conductor lines are collectively etched by an etchant (FIG. 6).
(E)).

Also in this method, the metal A and the etchant 1 are selected so that the relationship of the etching rate R ₁ with respect to the etchant 1 used in the step of FIG. The metals C and B and the etchant 2 are selected so that the relationship of the etching rate R ₂ with respect to the etchant 2 used in the step e) satisfies the condition of the above equation (2). By selecting appropriate metal species and etchant in this way, the lower part of the wiring is
The shape is as shown in (c) and no overhang occurs.

There are many possible combinations of metals and etchants that satisfy the above conditions (1) to (3). Here, as a reference for selecting a metal and an etchant satisfying a predetermined condition, Table 1 shows etching properties of various metal elements relative to various etchants. For the given etchants shown in Table 1, “double circle” is a metal that can be etched at room temperature, ◯ is a metal that can be etched at 100 ° C., and x is a metal that cannot be etched. Since the etching rate is higher in this order, the metal and etchant to be selected can be determined by referring to this table.

[0026]

[Table 1]

[0027]

Embodiments of the present invention will be described below with reference to the drawings. Example 1 According to the manufacturing process shown in FIGS. 4A to 4E, a laminated conductor wiring is manufactured as follows.

First, 0.1 μm thick Mo serving as a base conductor and 5 serving as a main conductor are formed on the surface of an alumina substrate by vacuum deposition.
After sequentially forming Cu with a thickness of μm, a photoresist pattern corresponding to a circuit pattern is formed by photolithography, and using this as a mask, phosphoric acid (77 vol%) + nitric acid (3 vol%) + acetic acid (15 vol%) + water (5vo
(1%) mixed solution is used as an etchant to etch away Cu having a thickness of 5 μm and Mo having a thickness of 0.1 μm all together. The etching rate of Cu at this time is about 0.4.
The etching rate of Mo is about 0.1 μm / min.

Next, 1 μm thick Mo to be the first coated conductor and 1 μm to be the second coated conductor are formed on the entire surface by vacuum deposition.
m thick Al is sequentially formed. Subsequently, a photoresist pattern is formed so as to surround the Cu / Mo wiring line, and this is used as a mask for phosphoric acid (95.4 vol%) +
Using a mixed solution of nitric acid (0.6 vol%) + acetic acid (3.0 vol%) + water (1.0 vol%) as an etchant, 1 μm-thick Mo and 1 μm-thick Al are collectively removed by etching. At this time, the etching rate of Mo is about 0.05 μm / min, and the etching rate of Al is about 0.08.
μm / min. Through these steps, a laminated conductor wiring without overhang can be formed in the lower portion as shown in FIG.

Then, polyamic acid as a polyimide precursor is spin-coated on the entire surface in a solvent atmosphere thereof under reduced pressure conditions so as to prevent bubbles from entering, and cured at 350 ° C. for 120 minutes. Form a photoresist pattern for contact hole drilling on the cured polyimide insulator,
Using this as a mask, chemical dry etching (CDE) of polyimide with a mixed gas of oxygen and carbon tetrafluoride
To form a contact hole. Further, a laminated conductor wiring of the second and subsequent layers is sequentially formed on this to manufacture a multilayer wiring board.

Example 2 According to the manufacturing process shown in FIGS. 6A to 6E, a laminated conductor wiring is manufactured as follows.

First, on a surface of a silicon substrate on which a thermal oxide film having a thickness of 0.2 μm is formed, 0.1 μm thick Mo serving as a base conductor and 1 μm thick Cu serving as a conductor for a plating electrode are sequentially formed by a DC magnetron sputtering method. Form a film. Next, after forming a photoresist pattern corresponding to a reverse pattern of the circuit pattern by photolithography,
Using a solution containing sulfuric acid, copper sulfate, and hydrochloric acid as main components, 40 μm of Cu, which is the main conductor, under the condition of current density 15 mA / cm ²
Electroplate up to m thickness. After that, the resist is peeled off using acetone and washed in pure water. At this time, since the plated conductor has an inverse taper shape of about 80 °, a resist pattern slightly thinner than its width is formed on the plated Cu conductor line, and this is used as a mask for phosphoric acid (77).
vol%) + nitric acid (3 vol%) + acetic acid (15 vol)
%) + Water (5 vol%) as an etchant to remove excess Cu by etching. As a result, the width of the plated conductor line is slightly reduced, but the inverse taper is almost eliminated. At this time, at the same time, the Cu film in the area (space portion) other than the line is also slightly etched. The Cu etching rate at this time is 0.4 μm / min.

Thereafter, a photoresist pattern is formed so as to surround the plated Cu conductor line, and using this as a mask, phosphoric acid (77 vol%) + nitric acid (3 vol%) +
Using a mixed solution of acetic acid (15 vol%) + water (5 vol%) as an etchant, the Cu film and M
The film is removed by etching at once. At this time, the etching rate of Cu is 0.4 μm / min, and the etching rate of Mo is 0.1 μm / min.

Subsequently, a 1 μm-thick Mo film which becomes the first coated conductor is formed on the entire surface by DC magnetron sputtering.
Then, 1 μm thick Al to be the second coated conductor is sequentially formed. At this time, by forming a film of Mo and Al under the condition that the step coverage of the substrate is good by taking measures such as increasing the Ar gas pressure, 0.5 μm or more is obtained even on the side wall of the plated Cu conductor having a thickness of 40 μm. Mo and Al
Can be attached. Then, a photoresist pattern is formed so as to surround the conductor line, and using this as a mask, phosphoric acid (95.4 vol%) + nitric acid (0.6 vol%) + acetic acid (3.0 vol%) + water (1.0 vol) %) As an etchant, and 1 μm thick Mo and 1
Al having a thickness of μm is collectively removed by etching. At this time, the etching rate of Mo is about 0.05 μm / min, and the etching rate of Al is about 0.08 μm / min. Through these steps, the thick film laminated conductor wiring without overhang can be formed in the lower portion as shown in FIG.

Then, polyimide is formed by the same method as in Example 1, and chemical dry etching is performed to form a contact hole. Further, a laminated conductor wiring corresponding to the circuit patterns of the second and subsequent layers is sequentially formed on this to manufacture a multilayer thick film wiring board.

Example 3 Using the process of Example 1, a flat type thin film air-core coil shown in FIGS. 7A and 7B is manufactured. FIG. 7A is a plan view and FIG. 7B is a sectional view. In FIGS. 7A and 7B, a planar air-core coil 32 composed of a single layer of laminated conductor wiring having the structure of FIG. 3A is formed on an alumina substrate 31. The coil pattern has a square spiral shape, the number of turns is 5, and the width of the laminated conductor line is 20 μm.
m, space portion 20 μm, and outer size 500 μm. Next, an SiO ₂ film 33 is deposited on the entire surface by plasma CVD as an interconductor insulating film and a protective film, and then R 4 is used with carbon tetrafluoride as a reaction gas using a resist as a mask.
The pad portion 34 is opened by the IE method to expose the Al surface.

This air-core coil operates normally as a DC choke of a transmission amplifier of an 800 MHz analog mobile phone. Example 4 A planar choke coil for a MHz switching power supply shown in FIGS. 8A and 8B is manufactured by using the process of Example 2. 8A is a plan view and FIG. 8B is a sectional view. 8A and 8B, a lower magnetic thin film 42, a SiO ₂ film 43, a coil 44, a polyimide film 4 are formed on a silicon substrate 40 having a thermal oxide film 41 on the surface.
5, the upper magnetic thin film 46 and the polyimide film 47 are sequentially formed, and the coil 44 has a structure sandwiched by the upper and lower magnetic thin films 42 and 46. In this choke coil, the magnetic thin film is given uniaxial magnetic anisotropy with the easy magnetization axis in the direction of the arrow in FIG. 8A so that the magnetic thin film is excited in the hard magnetization axis direction in most regions of the element. To do.

The method of manufacturing the choke coil will be described in more detail below. First, on the silicon substrate 40 on which the thermal oxide film 41 is formed, Al / AlN _x (x = 0.about.0.
5) / AlN _x (x = 0.5 to 1), a film (not shown) is formed in this order, and a film thickness of 6.0 μm is formed on the AlN _x (x = 0.5 to 1) by a sputtering method. Lower magnetic thin film 4
Form 2 This magnetic thin film is FeCoBC system and FeC
It is a hetero-amorphous magnetic film in which an amorphous magnetic phase containing a large amount of o and an amorphous insulating phase containing a large amount of boron and carbon are uniformly dispersed. 300 μΩ
・ Cm. Using this magnetic thin film as a mask, phosphoric acid (77 vol%) + nitric acid (3 vol%) + acetic acid (1
Etching is performed using a mixed solution of 5 vol%) + water (5 vol%) as an etchant. A SiO ₂ film 43 having a film thickness of 5.0 μm is formed thereon by a sputtering method, and a coil 44 made of a laminated conductor having a sectional structure shown in FIG. 3C is formed on the SiO ₂ film 43 by the same method as in the second embodiment. Form. The coil pattern has a shape in which two rectangular spiral coils wound in opposite directions are arranged side by side, the number of turns is 6, and the thickness of the Cu conductor is 50 μm. Then, a polyimide film 45 is formed between the lines of the coil 44 and on the line by the same method as in the first embodiment. After the upper surface of the polyimide film 45 is sufficiently flattened, an upper magnetic thin film 46 having a film thickness of 6.0 μm is formed by a sputtering method using the same material as the lower magnetic thin film 42, and is etched similarly to the lower magnetic thin film 42. To do. Further, a polyimide film 4 is formed on the entire surface as a protective film.
Form 7. Next, a resist pattern is formed in order to perform a hole forming process on the pad portion, and the polyimide film 47 is etched by chemical dry etching using a mixed gas of oxygen-carbon tetrafluoride using the resist pattern as a mask. Expose. Finally, in a vacuum, a DC magnetic field of 24 kA / m is applied in the arrow direction of FIG. 8A and heat treatment is performed at 320 ° C. to give uniaxial magnetic anisotropy.
The uniaxial magnetic anisotropy may be imparted by forming a soft magnetic thin film in a DC magnetic field.

The produced planar choke coil has an inductance of 0.5 μH, a DC coil resistance of 0.2 Ω,
DC current of which inductance decreases to 50% is 1.5A
Is.

This choke coil, a control IC that is a bare chip, a MOS FET for switching,
And Schottky diode for rectification, 50 μm
Wire bonding is performed with a Au wire having a diameter to form a step-up chopper type DC-DC converter operating at 5 MHz. This converter converts input voltage of 3.6V to 5.0V
The power conversion efficiency at the time of 3.0W output is 82%
Is.

In addition to the above embodiment, various electronic parts and magnetic parts can be manufactured by applying the present invention as shown below. For example, using the same method for manufacturing a laminated conductor wiring as in Example 2, a planar transformer having a shape in which primary and secondary laminated conductor coils are wound around a magnetic thin film as shown in FIG. 9 is manufactured. You can also Figure 9
In which the thermal oxide film 51 is formed
A lower conductor of the primary coil 52, a lower conductor of the secondary coil 53, a magnetic body 54, an upper conductor of the primary coil 52, and an upper conductor of the secondary coil 53 are stacked on top of each other in an insulated state. The lower conductor and the upper conductor forming each coil are formed in a predetermined pattern by the same method as in the second embodiment, and are connected to each other. The entire surface of this transformer is covered with a polyimide film 55,
Pad holes are formed on both ends of the primary coil 52 and the secondary coil 53.

Similarly, a thin film magnetic head for a hard disk drive as shown in FIG. 10 can be manufactured. In FIG. 10, the MR sensor 64 is embedded in the SiO 2 on the silicon substrate 60 on which the thermal oxide film 61 is formed.
₂ film 63, lower core 65 made of 2.0 μm thick CoZrNb amorphous soft magnetic thin film, SiO ₂ film 66 forming a recording gap of 0.1 μm at the head tip,
A laminated conductor coil 67 formed by the same method as in Example 2, a polyimide film 68 covering the periphery of the laminated conductor coil 67, and an upper core 69 composed of a 2.0 μm thick CoZrNb amorphous soft magnetic thin film are sequentially formed. There is. In addition to the embodiments described above, the laminated conductor wiring according to the present invention can also be used as wiring for a semiconductor device.

[0043]

As described above, according to the present invention, C
Improving process control and shortening the process of laminated conductor wiring with u as the main conductor, and practical use and cost reduction of electronic components such as multilayer wiring boards and magnetic components typified by inductors, transformers, and magnetic heads using the same Can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a conventional laminated conductor wiring.

FIG. 2 is a sectional view showing an example of a laminated conductor wiring according to the present invention.

3A to 3C are sectional views showing a laminated conductor wiring according to the present invention.

4A to 4E are cross-sectional views showing an example of a method for manufacturing a laminated conductor wiring according to the present invention.

5A to 5E are cross-sectional views showing another example of the method for manufacturing a laminated conductor wiring according to the present invention.

6A to 6E are cross-sectional views showing still another example of the method for manufacturing a laminated conductor wiring according to the present invention.

7 (a) and 7 (b) are a plan view and a cross-sectional view of a thin-film air-core coil manufactured in Example 3 of the present invention.

8A and 8B are a plan view and a cross-sectional view of a planar choke coil manufactured in Example 4 of the present invention.

FIG. 9 is a perspective view of a planar transformer manufactured according to another embodiment of the present invention.

FIG. 10 is a perspective view of a thin film magnetic head manufactured according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base insulator, 2 ... Base conductor, 3 ... Main conductor made of Cu, 4 ... First coated conductor, 5 ... Second coated conductor, 6 ... Surrounding insulator, 10 ... Bonding wire, 21, 22, Two
3, 24, 25, 26 ... Photoresist, 31 ... Alumina substrate, 32 ... Air core coil, 33 ... SiO ₂ film, 34 ...
Pad portion, 40 ... Silicon substrate, 41 ... Thermal oxide film, 42
... Lower magnetic thin film, 43 ... SiO ₂ film, 44 ... Coil, 4
5 ... Polyimide film, 46 ... Upper magnetic thin film, 47 ... Polyimide film, 50 ... Silicon substrate, 51 ... Thermal oxide film, 52 ...
Primary coil, 53 ... Secondary coil, 54 ... Magnetic material, 55 ...
Polyimide film, 60 ... Silicon substrate, 61 ... Thermal oxide film,
63 ... SiO ₂ film, 64 ... MR sensor, 65 ... Lower core, 66 ... SiO ₂ film, 67 ... Multilayer conductor coil, 68 ...
Polyimide film, 69 ... Upper core.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 27, 1995

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] Figure 8

[Correction method] Change

[Correction content]

[Figure 8]

Claims (7)

[Claims] 1. An electronic component having a conductor wiring covered with a base insulator and a surrounding insulator, wherein the conductor wiring is
Ti, T processed into a predetermined pattern on the surface of the underlying insulator
a, a Mo, Cr, Nb, W, a base conductor made of at least one selected from the group consisting of a, a main conductor made of Cu processed into a predetermined pattern on the base conductor, and a main conductor made of Cu. Of Ti, Ta, Mo, and N formed by sequentially laminating so as to cover the surface facing the surrounding insulator
a first coated conductor made of at least one selected from the group consisting of b and Ni, and a second coated conductor made of at least one selected from the group consisting of Au and Al. Electronic components to do. 2. An electronic component having a conductor wiring covered with a base insulator and a surrounding insulator, wherein the conductor wiring is
Ti, T processed into a predetermined pattern on the surface of the underlying insulator
a, a Mo, Cr, Nb, W, a base conductor made of at least one selected from the group consisting of a, a main conductor made of Cu processed into a predetermined pattern on the base conductor, and a main conductor made of Cu. On the exposed surface of the pattern
formed by sequentially stacking at least one selected from the group consisting of a, Mo, Nb, and Ni and at least one selected from the group consisting of Au and Al, and then removing the unnecessary portion by etching. An electronic component comprising: the first and second coated conductors. 3. When the etching rates of the main conductor Cu and the underlying conductor are R _{1, Cu} and R _{1, A} for the first etchant used when simultaneously etching them, R _{1, Cu} The etching rates for the second etchant used for simultaneously etching the first and second coated conductors satisfying the condition ≧ R _{1, A} are R _{2, B} and R _{2, C ,} respectively. At this time, the electronic component according to claim 1 or 2 _{, wherein} the condition of R _{2, C} ≧ R _{2, B} is satisfied. 4. The main conductor Cu, the base conductor, and the first and second conductors have etching rates of R _Cu , R _A , R _B , and R _C with respect to an etchant used when simultaneously etching them. The electronic component according to claim 1 or 2, wherein the condition of R _C ≧ R _B ≧ R _Cu ≧ _RA is satisfied. 5. A magnetic component having a coil made of a conductor covered with a base insulator and a surrounding insulator, wherein the coil is made of Ti, Ta, Mo, Cr, which is formed into a predetermined pattern on the surface of the base insulator. A base conductor made of at least one selected from the group consisting of Nb and W, a main conductor made of Cu processed into a predetermined pattern on the base conductor, and a surface surrounding the insulator around the main conductor made of Cu. Ti, Ta, formed by sequentially laminating so as to cover the surface
A first coated conductor made of at least one selected from the group consisting of Mo, Nb, and Ni; and a second coated conductor made of at least one selected from the group consisting of Au and Al. Characteristic magnetic parts. 6. When the etching rates of the main conductor Cu and the underlying conductor are R _{1, Cu} and R _{1, A} with respect to the first etchant used when simultaneously etching them, R _{1, Cu} The etching rates for the second etchant used for simultaneously etching the first and second coated conductors satisfying the condition ≧ R _{1, A} are R _{2, B} and R _{2, C ,} respectively. The magnetic component according to claim 3 _{, wherein} the condition of R _{2, C} ≧ R _{2, B} is satisfied. 7. The main conductor Cu, the base conductor, and the first and second conductors have etching rates of R _Cu , R _A , R _B , and R _C with respect to an etchant used for simultaneously etching these, respectively. 4. The magnetic component according to claim 3, wherein the condition of R _C ≧ R _B ≧ R _Cu ≧ _RA is satisfied.