JP3010066B2 - Optical excitation process equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a photoexcitation process apparatus used for manufacturing semiconductors, liquid crystal displays, and the like.

[Conventional technology]

In recent years, a photoetching apparatus that uses a light energy to decompose a halogen gas such as a chlorine gas to etch a silicon wafer or the like, or decompose a compound gas such as silane or disilane to form a thin film on a silicon wafer or a glass substrate The development of optical CVD equipment is being actively pursued. Since the photoexcitation process apparatus using these lights can lower the temperature of the process and does not cause deterioration of a substrate or a formed film due to charged particles, it is attracting much attention as a next-generation device manufacturing method.

A conventional photoexcitation process apparatus will be briefly described with reference to FIG. In FIG. 1, reference numeral 1 denotes a reaction chamber for accommodating a substrate 4 to be processed, and a reaction gas introduction system and an exhaust system are connected to an introduction port 5 and an exhaust port 6, respectively. A stage 2 on which a substrate 4 is mounted is installed in the reaction chamber 1, and is usually controlled at a constant temperature by a heater 3 or the like. This reaction chamber 1 is usually
It is connected to a light source chamber 8 via a jet plate 7 having a number of small holes made of quartz. The light source room 8 is provided with a light source 10 that emits a wavelength suitable for a photochemical reaction. The light source 10 can irradiate light onto the substrate 4 and an inert gas introduction system is also connected to the introduction port 9. It also forms an inert gas chamber.

The reaction gas is introduced in a sheet form from the reaction gas introduction system through the introduction port 5 substantially parallel to the surface of the substrate 4, and is decomposed or reacted by light having a suitable wavelength to deposit a thin film on the substrate 4. At this time, the inert gas introduced from the inert gas inlet 9 is passed through the ejection plate 7 having many small holes to the substrate 4.
The light source 10 is introduced into the reaction chamber 1 so as to face the surface of the lamp, so that film deposition on the lamp surface of the light source 10 can be prevented.

In the light-excitation process device configured as described above, the light source 10 which can be said to be the heart of the light-excitation process device is usually a high-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, a deuterium lamp, a rare gas resonance line lamp, or the like. In the light source, when a large-diameter silicon wafer of 6 to 8 inches or a large glass substrate for liquid crystal is used, it is difficult to irradiate light with uniform illuminance and high illuminance. There is a problem that the film thickness distribution is deteriorated. In particular, for light sources that generate relatively short wavelengths, such as deuterium lamps and rare gas resonance line lamps, the light transmitting materials that can be used are very limited. I didn't. Therefore, increasing the area of the light source is an essential and serious problem.

In order to cope with the above problem, the present inventors arranged a large number of relatively small discharge tube units (electrodes) as shown in Japanese Patent Application Laid-Open No. We have developed (invented) a new light source for photo-excitation process equipment, which is an improved large-area irradiation light source provided with a perforated partition. As shown in FIG. 3 (a), this lamp is housed in a hollow lamp house 11 having a cooling water passage therein.
A large number of small lamps 12 (19 in FIG. 1B) are arranged at equal intervals on a plane or a curved surface, and the periphery of each of these lamps 12 flows in from a cooling water inlet 13 and flows out from a cooling water outlet 14. The lamps 12 are cooled by cooling water, and a control device 15 is connected to each of the lamps 12 so that each of the lamps 12 is independently turned on / off, or emits a pulse of an arbitrary length.

[Problems to be solved by the invention]

The above-mentioned newly developed light source for a photoexcitation process apparatus has solved the above-mentioned essential and serious light source problem. However, according to the results of the subsequent study, in the photoexcitation process apparatus having the above-described configuration, as the size of the light source is increased, an ejection plate having many small holes made of quartz (corresponding to 7 in FIG. 4) is also provided. Although it is necessary to increase the size, it is very difficult to form a large number of small holes over such a large area, and a new problem that the cost increases. Furthermore, in a photo-excitation process device using a vacuum ultraviolet light source with a relatively short wavelength such as a deuterium lamp or a rare gas resonance line lamp, MgF ₂ , CaF ₂ , LiF, It has also been found that a very large material having only a very limited material such as sapphire is difficult to obtain and a brittle material, so that it is not possible to form small holes efficiently.

The present invention solves a new problem caused by using a large-area light source in which a large number of independent, relatively small lamps are arranged on a plane or a curved surface as described above, and can reduce the cost of an optical path at low cost. Provided is a photo-excitation process apparatus including a jet plate having a large number of small holes, which can be used for any size of light source and at any wavelength of light without obstruction. It is an object.

[Means for solving the problem]

In order to achieve the above object, the photoexcitation process apparatus of the present invention includes a reaction chamber containing a substrate to be processed, a unit for introducing and exhausting a reaction gas into the reaction chamber, and a photochemical reaction of the reaction gas. A light source having a large number of independent, relatively small lamps arranged on a plane or a curved surface for forming a thin film on the substrate, a light source chamber containing the light source, a reaction chamber and a light source chamber. An ejection plate having a large number of small holes is arranged therebetween, and the first gas flow is introduced in a sheet shape substantially parallel to the surface of the substrate accommodated in the reaction chamber, and is opposed to the surface of the substrate. In a photo-excitation process apparatus in which a second gas flow is introduced from a jet plate having a large number of the small holes to maintain a laminar flow state near the surface of the substrate, the independent, relatively small lamp is used. Between the ramps, a squirt plate with many small holes It is characterized in that it has location.

(Operation)

The photoexcitation process apparatus according to the present invention configured as described above uses a large-area light source in which a number of relatively small lamps are arranged on a plane or a curved surface, and therefore has many small holes between individual lamps. It is possible to dispose the blowout plate, and such an arrangement does not impede the optical path at all. Therefore, the light absorption in the ejection plate is zero, and the light from the light source can be used most efficiently, so that a uniform and high light illuminance can be obtained on a large-area substrate.
The jet plate with many small holes is optically opaque,
For example, since a metal such as stainless steel or aluminum can be used, drilling is easy, and therefore, it can be manufactured at low cost.

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a photo-excitation process apparatus showing one embodiment of the present invention, in which the same reference numerals as those shown in FIG. 3 (a) indicate the same or similar parts. .

In the figure, a large number of small lamps 12 (19 in this embodiment) are arranged at equal intervals on a plane or a curved surface in a hollow annular lamp house 11 in which a cooling water passage is formed. Is cooled by cooling water flowing in from a cooling water inlet 13 and flowing out from a cooling water outlet 14, and a control device 15 is connected to each lamp 12, and each lamp 12 is independently controlled. The point of turning on / off or pulse light emission of an arbitrary length is the same as the previously developed one (FIG. 3 (a)).

In the present embodiment, an inert gas chamber 30 is formed between the independent relatively small lamps 12 and the lamps 12, one side of which is connected to the inert gas inlet 29 in contact with the bottom of the lamp house 11, The inert gas chamber 30 is connected to the lower reaction chamber 21 via an ejection plate 31 having a large number of small holes and arranged on the same plane as the lower end of each lamp 12.

The reaction chamber 21 accommodates a substrate 24 to be processed, and a reaction gas introduction system and an exhaust system are provided with an inlet 25 and an outlet, respectively.
Connected to 26. A rotatable stage 23 on which a substrate 24 is mounted is installed in the reaction chamber 21, and is usually controlled at a constant temperature by a temperature control device 22 such as heating or cooling.

FIG. 2 is a plan view of the light source 20 in FIG.
The ejection plate 31 having a large number of small holes is provided with a large number of small holes 32 from which the inert gas is ejected at a portion other than the lamp 12. The ejection plate 31 may be made of any material as long as there is no problem with the reactivity with the released gas or the process gas and the workability, but from the viewpoint of cost, a metal material such as stainless steel or aluminum is preferable.

Next, the operation will be described. During operation, as shown by the dashed line in FIG. 1, the reactant gas is introduced into the sheet from the reactant gas inlet 25 almost in parallel to the surface of the substrate 24, and the gas flows. Decomposes or reacts with light of various wavelengths,
A thin film is deposited on 24. At this time, the inert gas introduced from the inert gas inlet 29 is introduced into the reaction chamber 21 through the ejection plate 31 having a large number of small holes so as to be opposed to the surface of the substrate 24, thereby causing a reaction near the substrate 24. In order to suppress the rise of the gas flow and to prevent the turbulent diffusion of the reaction gas component, the reaction gas component is pressed only near the substrate to prevent a film from adhering to the surface of the lamp 30.

Further, since a large-area light source having a large number of relatively small lamps 12 arranged on a plane is used as the light source 20, a large number of small holes 32 for ejecting an inert gas are provided between the individual lamps 12. It is possible to dispose the ejection plate 31 having the same, and such an arrangement does not impede the optical path at all. Therefore, the light absorption in the ejection plate 31 is zero, and the light from the light source can be used most efficiently.
Uniform and high light illuminance can be obtained. In addition, since the ejection plate 31 having a large number of small holes 32 can be made of an optically opaque metal such as stainless steel or aluminum, it can be easily drilled, and can be manufactured at low cost. it can.

In the above-described embodiment, the structure in which the ejection plate 31 and the lamp 12 are aligned on the same plane has been described. However, when the ejection plate 31 causes an optical path obstruction of light emitted from the side surface of the lamp 12, these lamps 12 May be arranged so as to protrude from the ejection plate 31. Further, although the structure in which the lamps 12 are arranged on a plane has been described, a large number of lamps 12 may be arranged on a curved surface.

Further, in the above-described embodiment, the structure in which the control device (system) 15 is separately connected to each lamp 12 and the light source 20 itself has a degree of freedom to form an arbitrary illuminance distribution has been described. Therefore, the control devices 15 may be combined into one.

In addition, as for the kind of relatively small lamp in the present invention, a high-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, a deuterium lamp, a rare gas resonance line lamp and the like are often used, but are not particularly limited. In the present invention, the number is preferably three or more from the viewpoint of illuminance and uniformity. The interval between the lamps is not particularly limited.
The denser the better, from the viewpoint of uniformity.

(Experimental example)

In an experiment using the photoexcitation process apparatus according to the present invention, 19 small deuterium lamps having a diameter of about 20 mm were arranged at regular intervals with a distance between the lamps of 40 mm on a plane similarly to the arrangement shown in FIGS. 3 (a) and 3 (b). To produce a large area light source. Further, a jet plate 31 made of stainless steel and having a large number of small holes 32 having a thickness of 3 mm and a diameter of about 0.6 mm was arranged between the individual lamps 12 as shown in FIG.

A 5-inch wafer was used as the substrate 24, disilane was used as the reaction gas, and argon was used as the inert gas. The amorphous silicon film was formed by heating the wafer at 250 ° C. for 1 hour while rotating the stage 23. , Amorphous silicon was deposited. When the film thickness of this deposited film was measured, good film thickness uniformity within ± 5% was obtained within a 5-inch wafer, and the average film thickness was about 2,000.
Was Å. This film formation experiment was repeated 50 times, but no film adhesion was observed on the lamp surface, and it was confirmed that complete prevention of film adhesion was realized.

〔The invention's effect〕

As described above, a large-area light source in which a large number of independent relatively small lamps are arranged on a plane or a curved surface, invented earlier by the present inventors, is provided with a squirt plate having a large number of small holes. Incorporation between the lamp and the lamp makes it possible to use a light source of any wavelength with a large area, high light use efficiency, and to use a light source of any wavelength. It is possible to obtain a photo-excitation process apparatus for a large-area substrate capable of performing the above.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a photo-excitation process apparatus showing one embodiment of the present invention, FIG. 2 is a plan view of a light source according to the present invention, and FIGS. 3 (a) and 3 (b) are first invented by the present inventors. FIG. 4 is a sectional view and a plan view of a large-area light source, and FIG. 4 is a sectional view showing a conventional example. 11 ... Lamp house, 12 ... Small lamp, 13 ... Cooling water inlet, 14 ... Cooling water outlet, 15 ... Control device, 20 ... Light source, 21 ... Reaction chamber, 22 ... Stage temperature control device ,twenty three…
... Stage, 24 ... Substrate, 25 ... Reaction gas inlet, 26
... exhaust port, 29 ... inert gas inlet, 30 ... inert gas chamber, 31 ... jet plate, 32 ... small hole.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/205 H01L 21/365 H01L 21/31 C23C 16/00-16/56

Claims (1)

(57) [Claims] A reaction chamber for accommodating a substrate to be treated, means for introducing and exhausting a reaction gas into the reaction chamber, and an independent means for photochemically reacting the reaction gas to form a thin film on the substrate. A light source having a large number of relatively small lamps arranged on a plane or a curved surface, a chamber for introducing an inert gas, and a spout having many small holes between the reaction chamber and the inert gas chamber. A plate is arranged, a first gas flow is introduced in a sheet shape substantially parallel to the surface of the substrate contained in the reaction chamber, and the second gas flow is supplied to the small holes so as to face the surface of the substrate. In a photo-excitation process apparatus in which a laminar flow state is maintained near the surface of the substrate by introducing a large number of small holes between the independent and relatively small lamps, Photo-excitation process equipment characterized by having a jet plate .