JPH0336272A - Photo-cvd device - Google Patents

Abstract

PURPOSE:To prevent a film from being stuck on a susceptor and to prevent generation of dust and to enhance film quality by providing a means for irradiating the rear of a wafer with light to heat it and reducing heating of the whole susceptor holding the wafer. CONSTITUTION:A photo-CVD device is formed of a reaction chamber, a susceptor 10 which is provided therein and holds a wafer 5 and a means 13 for irradiating the rear of the susceptor 10 with light to heat it. Further, a means 12 for reflecting the light with which the rear of the susceptor 10 has been irradiated is provided. Furthermore, one part of the susceptor 10 is formed of material low in thermal conductivity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photo-CVD apparatus, and more particularly to a photo-CVD apparatus having a susceptor for holding a wafer.

[Summary of the Invention] The present invention provides a photo-CVD apparatus having a reaction chamber and a susceptor for holding a wafer in the reaction chamber, by providing a means in the reaction chamber for heating the back surface of the wafer by irradiating it with light. The entire susceptor is less heated, preventing film adhesion to the susceptor and generation of dust 1- CV with good film quality
D film can be formed.

[Prior Art] Photo-CVD, which forms a thin film on a substrate by a photochemical reaction from a reactive gas, has the following advantages: growth can be performed at low temperatures, there is no damage to charged particles and the damage is low, and the reaction is It is attracting attention as a thin film forming technology for future ultrahigh-integration circuits because it can be rolled, allowing for good film formation, and when combined with a mask, it can be deposited in a selective location. .

Conventionally, as shown in FIG. 3, a photo-CVD apparatus for performing this type of photo-CVD mainly consists of a chamber 1a for isolating a reaction chamber 1 from the surroundings, and a susceptor 3 is provided above the reaction chamber I. A heater 2 for heating a substrate (wafer) 5 is attached inside the susceptor 3. A substrate holder 4 for mounting a substrate 5 is fixed to the lower part of the susceptor 3. In addition, chamber 1a
A window 6 is provided in the middle of the film for introducing light (ultraviolet light) that causes a photochemical reaction necessary for film formation and advances the reaction. This window 6 is provided at a position where the light transmitted through it can illuminate the substrate 5. Further, as the feed for the window 6, a monthly feed that transmits ultraviolet rays, such as quartz or magnesium fluoride, is generally selected.

A reactive gas, such as disilane gas, which causes a photochemical reaction and deposits a thin film of reaction products on the substrate 5 is introduced into the reaction chamber 1, and light is irradiated from the light source 7 to the substrate 5 through the window 6. Then, the disilane gas is decomposed and a thin film of amorphous silicon is deposited on the substrate 5''.

Furthermore, as a conventional device for preventing film deposition on a window that transmits light used in a reaction, an invention described in Japanese Patent Laid-Open No. 63-50026 is known.

[Invention solves the problem 1. However, in such a conventional optical C:VD device, in order to take advantage of the advantages of optical CVD, the substrate 5 is heated 1.
．． If the film is grown without it, the film quality will become unstable, which is a problem.

In addition, since the substrate 5 is heated by the heater 2 buried in the susceptor 3, the susceptor 3 body is heated, and film growth may occur on the susceptor 3, or a gas phase reaction may occur due to the heat of the susceptor 3. The problem was that nuclear growth occurred. Such film growth and nuclear growth cause dust generation, which has a negative impact on the ultra-high integrated circuits being manufactured.

The present invention was devised in response to these conventional problems [1], and provides an optical CVO device that prevents film adhesion to the susceptor, nuclear growth, etc., and suppresses the occurrence of It is something that you are trying to gain.

[Means for Solving 1 Problem] Therefore, the present invention provides an optical CVD apparatus that includes a reaction chamber and a susceptor that holds a wafer in the reaction chamber, and heats the back surface of the wafer by irradiating light onto the back surface of the wafer in the reaction chamber. The solution is to provide a means to do so.

[Effect 1: By heating the wafer by irradiating light from the back side,
This prevents the entire susceptor from being heated and prevents film growth and nucleus growth from occurring on the susceptor.

Therefore, it is possible to prevent dust from being generated from the susceptor side, and it is possible to form a CVD film with good film quality.

In addition, by providing a light reflecting means on the back surface of the susceptor,
Prevents the susceptor from being heated by light irradiation.

Furthermore, by forming at least a portion of the susceptor from a material with low thermal conductivity, heating of the susceptor can be prevented.
Suppresses film growth and nuclear growth on the susceptor.

[Example] Hereinafter, details of the optical CVD apparatus according to the present invention will be explained based on an example shown in the drawings.

(First Embodiment) FIG. 1 is a partial cross-sectional view showing the main parts of a photo-CVD apparatus according to the present invention.

The present embodiment includes a susceptor 10 for placing and holding a wafer 5 in a reaction chamber (not shown), and other configurations are substantially the same as those of the conventional example.

The susceptor IO has an opening in the center with a slightly smaller diameter than the wafer 5.
11 is opened, and the wafer 5 is opened at one side periphery of the opening I+.
A stepped portion 10a is formed for placing the.

Further, the inner wall and other side surfaces of the opening 11 of the susceptor 10 are coated with an aluminum thin film I2 serving as a light reflecting means, as shown in FIG.

and. On the other side of the susceptor IO, a halogen lamp 13 serving as a heating means for the wafer 5 is arranged. Further, on one side of the susceptor IO, a light source (not shown) for irradiating ultraviolet light (7) and subjecting it to a photochemical reaction is disposed.

In the embodiment, since the light emitted from the halogen lamp 13 is reflected by the aluminum thin film 12,
The susceptor 10 is not heated, and film growth by photo-CVD,
Nuclei growth due to heat-induced gas phase reactions does not occur on the susceptor 10. Note that the wafer 5 is exposed to a halogen lamp 13.
It is heated by light irradiation from. Therefore, it is possible to form a CVD film with good film quality.

(Second Embodiment) FIG. 2 is a partial sectional view showing a second embodiment of the optical CVD apparatus according to the present invention.

This embodiment (1) Open the susceptor IO from one side to the other side and install the opening [111]. Next, form the wafer 5 with this flange portion 101).
Second, it was designed to be able to be maintained.

In addition, the flange part] One side of 0'll and the opening 1'1
A heat insulating layer 14 made of quartz is integrally provided as a part of the susceptor 10 on the upper half surface of the inner wall 1 and the surface 10-L of the susceptor 10.

Note that the other configurations are the same as those in the first embodiment described in -1-.

In this way, a part of the susceptor IO is formed with the heat insulating layer 14 having a low thermal conductivity, so that even if the susceptor 10 is heated by the halogen lamp 13, the surface on one side of the susceptor where the photochemical reaction occurs (The heat insulating layer 13) is not heated and film growth by photo-CVD does not occur.

The above is a description of the first and second embodiments.1. However, the present invention is not limited to this, and various design changes are possible.

For example, in the first embodiment, the aluminum thin film I2
Although this is used as the luminous intensity measuring means, it is of course possible to provide a light reflecting plate made of other materials.

Further, in the second embodiment, the heat insulating layer 14 is formed as a part of the susceptor, but the entire susceptor may of course be formed of quartz or other material with low thermal conductivity.

Furthermore, in the first and second embodiments, the halogen lamp 13 is used as a means for heating the wafer 5), but other light irradiation means or microwaves may be used.

Furthermore, the present invention is applicable to CVD other than optical CVD.

[Effect of the invention] As is clear from the explanation below, the optical CV according to the present invention
T) The device reduces the heating of the entire susceptor, suppresses the formation of deposits on the susceptor, prevents the generation of dust during the manufacturing process of semiconductor devices, and produces CVD films with good film quality. There is an effect that can be formed.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing a first embodiment of the optical CVD apparatus according to the present invention, FIG. 2 is a partial sectional view showing the second embodiment, and FIG. 3 is a conventional optical CVD apparatus. FIG. 5...Wafer, ]0 - Susceptor, 11 - Opening, 12
...Aluminum thin film, 13...Halogen lamp,
14...Insulating layer. 1st Shima YIJ and the 9th division's side view Figure 1 top ■ 13 [// Figure 2 I ALL Ida 11's @ side Figure 8

Claims (3)

[Claims] (1) An optical CVD apparatus having a reaction chamber and a susceptor for holding a wafer in the reaction chamber, characterized in that a means for heating the back surface of the wafer by irradiating light with light is provided in the reaction chamber. (2) The optical CVD apparatus according to claim 1, further comprising means for reflecting light irradiated onto the back surface of the susceptor. (3) The optical CVD apparatus according to claim 1, wherein at least a portion of the susceptor is formed of a material with low thermal conductivity.