JPH0562908A - Substrate supporting stand for cvd thin film forming device - Google Patents

Abstract

PURPOSE:To obtain the substrate supporting stand for a CVD thin film forming device provided with a heating structure with which the surface to be treated can be heated up uniformly as much as possible even when the objective surface of treatment, requiring the formation of a thin film, becomes large in area by the formation of a large-calibered substrate. CONSTITUTION:In the substrate retaining stand of a CVD thin film forming device, provided with a heating device 7a with which a thin film 6 is formed on a substrate 4 while it is being retained, a coating layer 8, made of far infrared ray radiation material, is formed on the surface of the retaining part of the substrate retaining stand of a thin film forming device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a CV having a heating means for holding a substrate and forming a thin film on the substrate.
The present invention relates to a substrate holder of a D thin film forming apparatus.

[0002]

2. Description of the Related Art A conventional CV equipped with such a substrate holder.
The structure of the D thin film forming apparatus is shown in FIG. This apparatus 1 has a thin film forming chamber 1 in which the internal pressure can be adjusted.
The thin film forming chamber 1a is provided with a raw material gas supply passage 2 for supplying the raw material gas g and a raw material gas discharge passage 3 for discharging the raw material gas g from the thin film forming chamber 1a. Further, in the central portion 1c of the thin film forming chamber 1a, the above-mentioned substrate holding base 7 on which the substrate 4 to be thin film formed is placed is arranged, and the substrate holding base 7 has the resistance heating body 7a therein. The heating element 7a heats the raw material gas g and the film being formed. Further, a laser beam irradiation window 10 is provided in the thin film forming chamber 1a, and the source gas g in the upper region of the substrate is excited by the laser beam 9 introduced through the window 10. At the time of film formation, the substrate holder 7 and its vicinity are at a temperature suitable for formation (700 to 700 when the source gas is excited and the film formation promoting energy is supplied only by heat).
A thin film is formed by keeping the temperature at 800 ° C. and 350 ° C. or less when a laser is shared (mainly by the heating by the resistance heating body 7a described above).

[0003]

However, in such a substrate holder, in the conventional resistance heating element, generally, a thin rod-shaped member is appropriately arranged according to the shape of the object to be heated. .. For example, when the object to be heated has a disk shape like a wafer, the above-mentioned thin plate rod-shaped member is wound into a claw shape to form this. Then, a metal as a heat transfer medium is merely provided between the resistance heating element and the substrate. Therefore, in such a substrate holder, between the portion having the resistance heating element (immediately above the thin rod-shaped member) and the portion having no resistance heating element (immediately above the middle portion of the thin rod-shaped member), A non-uniform portion of the heating state and eventually the temperature state is generated. As a result, the substrate to be heated is non-uniformly heated two-dimensionally, and the thin film formation on the substrate occurs unevenly, leaving a problem in the film performance. For these reasons, the yield of finished products is poor, and when the situation is bad, about 40% of defective products may be produced. This tendency is particularly remarkable since the diameter of the substrate on which a thin film is formed has recently been increased. Therefore, an object of the present invention is to heat the substrate as uniformly as possible, for example, even when the substrate has a large diameter and the area of the object to be processed that requires thin film formation is large,
It is to obtain a substrate holder of a CVD thin film forming apparatus having a heating structure capable of forming a uniform thin film.

[0004]

To achieve this object, the substrate holding table of the CVD thin film forming apparatus according to the present invention is characterized in that a coating layer of far-infrared radiation material is formed on the surface of the holding portion holding the substrate. The actions and effects are as follows.

[0005]

That is, in the substrate holder of the present application, the far infrared ray emitting material formed on the surface of the holder is first heated by the heating means in the substrate holder. Far-infrared heating is an efficient heating method for ceramics, polymers, fibers, woods, resins, etc. whose absorption wavelength is generally 3 microns or more. Then, the far infrared rays emitted from the far infrared ray emitting material supply the raw material gas with energy necessary for forming a thin film. Here, in the present application, since the above-mentioned far-infrared radiation material is coated on the surface of the holding portion, the heat generated partially unevenly distributed from the resistance heating body is converted into infrared rays to form a thin film. The target substrate is surface-dispersed and uniformed over the entire surface and supplied. Of course, some of the energy is also transferred by normal heat transfer. Therefore, the energy required for forming the thin film is supplied to the substrate in a planar manner and evenly due to the properties of the far infrared ray material. As a result, in forming the thin film, the distribution of nuclei necessary for forming the film is made uniform, and the film grown centering on the nuclei also grows uniformly. The thin film thus formed is uniform and homogeneous along the surface of the substrate, and a good thin film can be obtained.

[0006]

Therefore, it is possible to obtain a thin film having a good film quality, as compared with the conventional case where the resistance heating element heats the substrate in a non-uniform manner to heat the substrate. It was Further, for example, far-infrared rays are not absorbed by the Si substrate which is a single crystal and are transmitted therethrough. Therefore, when the substrate is a Si substrate, the Si substrate is not unnecessarily heated, and distortion or cracking due to the heat of the substrate It became possible to avoid etc. On the other hand, for the same reason, since the energy is directly supplied to the reactants (raw material gas and thin film), it becomes possible to activate the reactants and increase the film forming speed. As described above, if the configuration of the present application is adopted from various elements, a good thin film can be formed, and the yield of the product is remarkably increased (the yield of the conventional example is about 60%, It was about 90% by adopting.).

[0007]

Embodiments of the present application will be described with reference to the drawings. FIG. 1 is a CVD thin film forming apparatus 1 including a substrate holder 7 of the present application.
The structure of is shown. This CVD thin film forming apparatus 1
This is a so-called laser CVD thin film forming apparatus, in which the source gas is decomposed / excited / formed by heat energy supplied by a heating element and energy supplied by laser light. Since this laser CVD thin film forming apparatus can form a thin film at a lower temperature than a conventional simple CVD thin film forming apparatus, it has an advantage that a substrate or the like is less thermally damaged and a good film can be formed. I have it. The case where the thin film 6 is formed on the semiconductor (IC, LSI, etc.) substrate 4 will be described below as an example. Here, the substrate 4 is exemplified by a silicon substrate, and the thin film 6 of silicon oxide, which is an insulating film or a passivation film, is formed on the substrate 4.

First, the configuration of the device 1 will be described.
This apparatus 1 is provided with a thin film forming chamber 1a whose internal pressure can be adjusted, and a raw material gas supply path 2 for supplying a raw material gas g into the thin film forming chamber 1a and a thin film forming chamber A source gas discharge path 3 for discharging the gas from the chamber 1a is provided. Further, a substrate holding table 7 on which the substrate 4 to be a thin film is placed is provided in the central portion 1c of the thin film forming chamber 1a. The substrate holder 7 is configured to have a resistance heating body 7a as a heating means therein, and a holding portion surface 7b of the substrate holder 7 has a coating layer 8 of aluminum oxide as a far infrared ray emitting material. Are formed. Further, a laser beam irradiation window 1 in which a laser beam 9 for exciting the source gas g on the substrate is introduced into the thin film forming chamber 1
0 is provided, and an excimer laser 11 that is a laser light source that oscillates the laser light 9 is provided on a side portion of the apparatus 1. Further, a laser light exit window 12 through which the laser light 9 is led out of the thin film forming chamber 1a is provided.

The case of forming the thin film 6 on the substrate 4 using the apparatus 1 of the present application will be described below. This board 4
The vicinity of the part is maintained in a temperature range of about 350 ° C. by the resistance heating body 7a, and SiH ₄ and N ₂ O as the source gas g are supplied from the source gas supply passage 2. This source gas g
Are diffused and supplied to the upper region 4a of the substrate. On the other hand, the substrate holder 7
In this case, the pedestal 7 is heated by the resistance heating body 7a, and the aluminum oxide coating layer 8 is also heated to emit far infrared rays L from the layer 8.
That is, the source gas g is decomposed and excited by receiving energy from the far infrared rays L and the laser beam 9 described above, and a thin film is formed. Then, the raw material gas g is excited and dissociated at the site 4 a on the substrate, and SiO 2 is deposited on the substrate 4.
_Two films will be grown. In this way, it becomes possible to form a film on the substrate 4.

In the structure of the present application, since the far infrared rays L supplied by the coating layer 8 of the far infrared radiation material formed on the substrate holding base 7 advances the film formation in this film formation, the raw material gas g In addition to being able to spatially evenly heat the substrate, the spatial heat distribution is even and good even at the film forming stage.
Therefore, it is possible to form a more uniform and uniform film than the conventional one.

[Other Embodiments] Other embodiments of the present application will be described below.
Bullet into. (A) FIG. 2 shows the configuration of another embodiment of the present application.
In the above embodiment, the substrate holder 7 has a substantially flat plate shape.
An example of providing a coating layer 8 of far infrared radiation material of
However, the substrate surface was made concave with the bottom side, and the substrate surface
It is also possible to supply far infrared rays L in a concentrated manner.
Noh. In this case, increase energy efficiency
Concentration of the excitation and / or dissociation part of the gas in the upper part near the substrate
It is possible to improve the efficiency and film formation efficiency. (B) Further, in the above embodiment, the laser light 9 is
Laser CV used as a means for decomposing / exciting source gas
An example of adopting the configuration of the invention of the present application to the D device has been shown.
The invention of the present application is to supply heat energy to a raw material gas etc.
For anything that forms a film
Can be adapted. Examples of such things are:
There is a simple thermal CVD device. (C) Further, in the above-mentioned embodiment, S is formed on the Si substrate.
iO₂Although the example of forming a film has been described,
Then, (SiH_Four NH₃), (Si₂H₆ NH ₃) One
When using as a pair to form a SiN film
Also, the configuration of the present application can be adopted. On board
This does not matter as to the type of film formed.

(D) As far-infrared radiation materials,
Any substance can be used as long as it efficiently radiates infrared rays corresponding to the absorption wavelength of the SiO ₂ or SiN film in the infrared region. In addition to the above aluminum oxide, aluminum titanate, Si
There are also C, MnO ₂ , ZrO ₂ , Cr ₂ O ₃ , TiO ₂ TiN and the like. In particular, transition metal oxides are often desirable because they generally have a radiation characteristic close to that of a black body.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a CVD thin film forming apparatus of the present application.

FIG. 2 is a diagram showing the configuration of another embodiment of the CVD thin film forming apparatus of the present application.

FIG. 3 is a diagram showing a configuration of a conventional CVD thin film forming apparatus.

[Explanation of symbols]

 4 Substrate 6 Thin Film 7a Heating Means 8 Coating Layer L Infrared g Raw Material Gas

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoji Dohi Osaka Prefecture Osaka City Chuo-ku Hiranomachi 4-1-2 1-2 Osaka Gas Co., Ltd.

Claims (1)

[Claims] 1. A substrate holding table of a CVD thin film forming apparatus, comprising a heating means (7a) and forming a thin film (6) on the substrate while holding the substrate (4), wherein the substrate (4) is A substrate holder of a CVD thin film forming apparatus in which a coating layer (8) of a far-infrared emitting material is formed on the surface of a holding portion for holding.