JPS5941842A - Chemical vapor deposition device - Google Patents

Abstract

PURPOSE:To narrow a space between substrates, and to improve capability for treatment by setting up a gas introducing pipe introducing a reaction gas and a second reaction pipe encasing a first reaction pipe in the first reaction pipe encasig a sample. CONSTITUTION:A quartz pipe 15 is installed in the reaction quartz pipe 14 of a CVD device 11, and two series of the gas introducing pipes 16, 17 are welded along a slit formed to the outer circumference of the quartz pipe 15. The slit functions as a scoop-out window along the outer circumference of the quartz pipe 15, and the reaction gas is introduced into the quartz pipe 15 from the jets of the gas introducing pipes 16, 17. The substrates 12 placed on a susceptor 13 are encased in the quartz pipe 15, and the inside of the pipe 15 is decompressed up to fixed pressure while being heated at a fixed temperature of approximately 425 deg.C by a heater 18. A substance, such as monosilane (SiH4), phosphine (PH3) or the like is introduced into one gas introducing pipe 16 and a substance such as oxygen (O2) into the other gas introducing pipe 17 and a gas reaction is induced, and the surfaces of the substrates 12 are coated with PSG films (SiO2- P2O5).

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to an apparatus used for forming a phosphorous silicate glass film (CVD-PSG) or the like used as a final protective film for an integrated circuit board. Particularly related to CVD equipment that increases the number of wafers processed (b) Technology Background As the degree of integration of semiconductor devices increases, the manufacturing process passes through multiple and diverse steps, and unstable factors tend to increase. . For example, adsorption of various gases and ionic substances is an unstable factor from the outside world.

This induces the formation of an inversion layer and the generation of interface states in the silicon bulk, which affects device characteristics.

On the other hand, instability factors that are present or generated in the circular part, such as a phenomenon in which the inside of the oxide film contains alkali ion contamination during film formation or during the treatment process, are caused to move inside the oxide film due to the electric field. Furthermore, in the 'VIO8 type configuration, there is an increase in inter-electrode leakage current and fluctuation in surface potential caused by sodium ion contamination.

The padding technology that removes these external and internal instability factors has become an important 'fx' issue in recent years, and the conditions required for the final protective film are as follows: It has excellent resistance to sodium-17ium ion contamination and is particularly effective at low temperatures. C film formed by
VD-PSGi is widely used.

(C) Prior Art and Problems FIG. 1 is a block diagram showing a conventional low-temperature, low-pressure CVD apparatus for forming a CVD-PSG film.

2 is a sectional view taken along line A-AI in FIG. 1.

The substrate 2 is placed on a susceptor 3 and housed in a low-temperature reduced pressure CVD apparatus 1 (hereinafter referred to as a CVD apparatus) for forming a PSG film. CVI) The apparatus 1 is equipped with a reaction quartz tube 4 whose pressure is reduced to a constant pressure through an exhaust port 5, and a gas inlet tube 6゜7 made of two series of stainless steel pipes inside the tube. It has a heater 8 that heats the film at 425° C. so as to accelerate the temperature and obtain a uniform film thickness.

Monosilane SiH4° phosphine PH3 is introduced into one series of gas introduction pipes 6, and oxygen 02 is introduced into the other gas introduction pipe 7. The gas introduction tubes 6 and 7 are stainless steel pipes with a diameter of 1/4 inch and are equipped with a shower-shaped spout 9, which induces a gas reaction by introducing gas into the reaction quartz tube 4.
A PSG film (SiOz-PzOs) is formed on the surface.

The substrates 2 are arranged back-to-back, and the intervals between them are CV. 1) The number of substrates to be processed is determined by setting the optimum film thickness distribution depending on the configuration conditions of the apparatus 1.

In other words, it is the processing capacity of the CVD apparatus l.

A specific example thereof will be explained with reference to FIG.

To find the appropriate value for the spacing l between substrates 20, b = 2 (R
1-R2). As is clear from the figure, 1]-Rz=d, so h=2d 1, hit d
The distance between the substrates can be narrowed and the number of substrates processed can be increased.

The persistent reaction quartz v4 is subject to restrictions because gas introduction g6 and g7 are involved.

(d) Object of the Invention In view of the above points, the present invention aims to provide a gas introduction mechanism that narrows the distance between substrates in a CVD apparatus and improves processing capacity.

(e) Structure of the Invention According to the present invention, the above-mentioned object includes a first reaction tube that accommodates a sample, and a reaction tube that is attached along the length direction on the outside of the first reaction tube, Providing a gas introduction tube for introducing gas and a second reaction tube for accommodating the first reaction tube (achieved by C).

(“) Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3 is a configuration diagram showing a CVD apparatus which is an embodiment of the present invention. A quartz tube 15 is again installed in the reactive quartz tube 4 of the CVD apparatus 11, and two series of gas introduction tubes 16 and 17 are fused along the slit provided on the outer periphery of this quartz tube 15.

The slit forms a hollow window along the outer circumference of the quartz tube 15, and the reaction gas is introduced into the quartz tube 15 from the gas introduction tube 16° 170 outlet (see FIG. 1, 9).

The substrate 12 placed on the susceptor 13 is housed in the quartz tube 15, and the pressure is reduced to a constant level and the tube is heated to a constant temperature of about 425° C. by the heater 18.

One series of gas introduction pipes 16 is filled with monosilane (SiH2) and phosphine (PH3), and the other gas introduction pipe 17 is filled with oxygen (oxygen).
02) is introduced to induce a gas reaction on the surface 1' of the substrate 12.
An mPsG film (8302-P2O3) is formed.

Using the CVD apparatus 11 configured in this way, the substrate 12
The substrate spacing h' for obtaining the optimum film thickness distribution can be reduced compared to the conventionally configured CVD apparatus, and the processing capacity can be improved.

FIG. 4 is a sectional view taken along line B-B' in FIG.

In the figure, if the radius of the quartz tube 15 is rb and the radius of the substrate 12 is r2, the optimum substrate spacing h/ can be expressed by the following equation as described above.

h'= 2 (rl - r 2 ) As is clear from the figure, since rl<Rh (r 1 -
r 2 )=D<d. Therefore, h'== 2D(
h, which is greatly improved compared to h=2d in the conventional configuration (see FIG. 2).

The appropriate spacing value obtained in the embodiment of the present invention is the CV of the conventional configuration.
With the D device, it became possible to set the pitch to 9.52 inches against a pitch of 14.28 meters.

Conventionally, in order to increase the number of film formation processes for substrates, it was necessary to perform so-called back-to-back batch processing in which the surface of the substrate is placed outside, but with the CVD apparatus 11 of the present invention, an increase in the number of film formation processes can be expected. It is also possible to consider arranging them at equal intervals in the same direction, which has the advantage of making it possible to adopt an automatic material feeding system.

(g) Effects of the Invention As explained in detail above, the CVD apparatus equipped with the gas introduction mechanism of the present invention has improved processing capacity compared to the conventional one.
It has excellent effects such as promising automation.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram showing a conventional CVD apparatus, and Figure 2 is a diagram showing the configuration of a conventional CVD apparatus.
3 is a sectional view taken along line hA in the figure, and FIG.
FIG. 4 is a block diagram showing the VD device, and FIG. 4 is a sectional view taken along line B-B' in FIG. In the figure, 11 is a CVD device, 12 is a substrate, 13
is a susceptor, 14 is a reaction quartz tube, 15 is a quartz tube, 16.
17 indicates a gas introduction pipe and 18 heaters. spear/i

Claims (1)

[Claims] a first reaction tube that accommodates a sample; a gas introduction tube that is attached along the length of the outside of the first reaction tube and that introduces a reaction gas into the first reaction tube; A CVD characterized by comprising a second reaction tube accommodating the reaction tube.
Device.