JPH037752B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vapor phase growth apparatus capable of epitaxial growth processing on a large number of semiconductor wafers at the same time.

[Prior art]

As this type of vapor phase growth apparatus, apparatuses such as those shown in FIGS. 4 and 5 are conventionally known. FIG. 4 is a schematic cross-sectional view showing a conventional vapor phase growth apparatus, in which a susceptor 33 is horizontally rotatably arranged in the center of a bell gear 32 through a base 31, and below this susceptor 33 is a high-frequency heating coil. 34 arranged,
Further, a plurality of semiconductor wafers (hereinafter simply referred to as wafers) 35 are placed on the susceptor 33, and the susceptor 33 is heated by the coil 34, and the susceptor 35 is heated and maintained at a predetermined temperature with the heat of the susceptor 33. Through the nozzle 36 introduced into the bell gear 32 through the shaft portion 33a of the bell gear 33, the required raw material gas is supplied and passed through the bell gear 32, so that epitaxial growth can be performed on the wafer 35. There is.

FIG. 5 is a schematic cross-sectional view showing a conventional barrel-type vapor phase growth apparatus, in which a plurality of susceptors 44 are assembled in a polygonal pyramid shape around a shaft 43 that is rotatably suspended in a bell gear 42 through a substrate 41. and fix it.
A plurality of wafers 45 are provided on the surface of each susceptor 44.
and the bell gear 4 corresponding to this susceptor 44.
A high-frequency heating coil 46 is disposed on the outer periphery of the bell gear 2, and while the shaft 43 is rotated, the coil 46 heats the wafer 45, and the raw material gas is introduced into the bell gear 4 through an inlet 47 opened at the upper part of the peripheral wall of the bell gear 42.
2 and flow through the bell gear 42 to allow epitaxial growth to occur on each wafer 45.

[Problem that the invention seeks to solve]

However, in the conventional vapor phase growth apparatuses as described above, there are problems such as the density of the wafers occupying the space inside the bell gear is small, the number of wafers to be processed is small, and the uniform heating effect of the wafers due to radiation is also small. Ta. For this reason, in the past, as a means to increase the number of wafers processed, increase the density of wafers in the space inside the bell gear, and improve the heat uniformity effect,
A disk-shaped susceptor is placed on a rotating plate placed inside the bell gear, and a radiation plate is placed around the axis. Wafers are fixed on both sides of each susceptor to increase the density of wafers and susceptors in the bell gear. A vapor phase growth apparatus has been proposed in which the number of wafers to be processed and the uniform heating effect of wafers due to radiation are increased (Japanese Patent Application Laid-open No. 7899/1983).

However, with such equipment, although the wafer area can be increased, the number of wafers processed is at most 4th,
There is a desire for a vapor phase growth apparatus that is only about twice as large as the apparatus shown in FIG. 5 and has a large processing capacity for large wafers.

[Means for solving problems]

The present invention has been made in view of the above circumstances, and its purpose is to erect a plurality of supports on a substrate, to mount susceptors in multiple stages between the supports, and to place a plurality of susceptors on each susceptor. By mounting the wafers, it is possible to simultaneously perform vapor phase growth on a large number of wafers with high efficiency, and the radiation provides a uniform heating effect on the wafers, improving the quality of the epitaxially grown film itself. The object of the present invention is to provide a vapor phase growth apparatus that can obtain the desired results.

The vapor phase growth apparatus according to the present invention includes a frame on which a plurality of susceptors are formed in an annular shape or arranged in an annular shape on a horizontal rotating plate installed in a bell gear, and are erected on the horizontal rotating plate. In a vapor phase growth apparatus in which susceptors are arranged in multiple stages with a required interval between each susceptor and a semiconductor wafer can be placed on the top surface of each susceptor, the outer periphery of the susceptor is placed facing the rotation area of the susceptor. A plurality of air supply pipes facing the rotating region of the inner circumference of the susceptor and having different source gas blowing height positions are arranged. .

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof. FIG. 1 is a schematic cross-sectional view of a vapor phase growth apparatus according to the present invention (hereinafter referred to as the present invention apparatus), and FIG. 2 is a vertical cross-sectional view taken along the - line in FIG. indicates Berjia. The bell gear 2 is formed into a cylindrical shape with a closed upper end using a heat-resistant material such as quartz, and has a lower end fixed on the base 1. On the outside of the bell gear 2, there is a water cooling jacket 3 that has approximately the same diameter and is slightly larger, and inside the bell gear 2, there are a rotary plate 4, a frame 5, a susceptor 6, a wafer 7, a main heater 8, and an auxiliary heater 9.
etc. are arranged. The water cooling jacket 3 is constructed by wrapping a water cooling tube 3b around the outer periphery of a cylindrical inner shell 3a made of a heat-resistant metal such as stainless steel, and has a cooling gas inlet 3c on the top surface.
There are multiple exhaust ports 3 on the lower circumferential surface.
e is open. Inner shell 3 of water cooling jacket 3
The circular diameter of a is slightly larger than the outer diameter of the bell gear 2, and there is a cooling gas passage 3d between the bell gear 2 and the bell gear 2.
It is arranged so as to surround the outside of the bell gear 2 across a gap that constitutes the bell gear 2, and its lower end is positioned concentrically with the bell gear 2 on the base 1. The bell gear 2
It is designed to provide cooling.

The rotating plate 4 is formed into a disk shape using a heat-resistant material such as silicon carbide or other heat-resistant material, and a shaft portion 4a is integrally formed with the same material at the center of the lower surface. protrudes downward through the base 1 and is connected to a drive unit (not shown) so that it can be rotated at a predetermined speed.

A plurality of mounts 5 are erected on the upper surface of the rotary plate 4 at regular intervals in the circumferential direction, and a plurality of susceptors 6 are stacked and stacked on the adjacent mounts 5 at required intervals in the upper and lower directions. In addition, a plurality of main heaters 8 are located outside the rotation range of the rotary table 4 between the peripheral wall of the bell gear 2, and a plurality of auxiliary heaters 9 and a source gas are located at the rotation center of the rotary table 4. air supply pipe 1
0 are arranged upright. The pedestal 5 is made of silicon carbide or other heat-resistant material and has a fan-shaped portion 5a and an extending portion 5b from the fan-shaped portion 5a as shown in FIG. It is erected at a required height with the extension portion 5b positioned on the rotation center side. In this state, both side surfaces of the fan-shaped portions 5a of adjacent frames 5 are parallel to each other, and on both sides of the frame 5 including these portions, there are thick susceptors 6 at predetermined intervals in the upward and downward directions. A large number of recessed grooves 5c having a width slightly larger than that of the rotary plate 4 are formed, and the susceptor 6 is inserted and placed removably from the peripheral edge side of the rotary plate 4 across the recessed grooves 5c of the adjacent mounts 5. There is. The susceptor 6 is formed into a hexagonal plate shape, and is mounted on the pedestal 5 with both side edges engaged in the corresponding grooves 5c of the adjacent pedestals 5, 5, and a circular shape is formed on the top surface of the susceptor 6. A wafer 7 is placed thereon.

The main heater 8 is formed in an arc shape between the rotary plate 4 and the rotating range of the pedestal 5 erected thereon and the inner circumferential wall of the bell gear 2, and is spaced apart from each other at a constant interval in the circumferential direction. A plurality of auxiliary heaters 9 are arranged to stand apart from each other, and a plurality of auxiliary heaters 9 are also arranged on the circumference inside the rotation area of the pedestal 5 on the rotary plate 4 and are arranged at regular intervals in the circumferential direction. It is located. Each main heater 8 penetrates the base 1 and is erected at approximately the same height as the pedestal 5, and the base 1 between the main heaters 8
A plurality of exhaust ports 1a for raw material gas are opened in the opening.

Each of the auxiliary heaters 9 is introduced into the bell gear 2 through the shaft portion 4a of the rotary plate 4, and is erected at approximately the same height as the pedestal 5. A plurality of raw material gas supply pipes 10 are arranged.

Each air supply pipe 10 is constructed by opening an air outlet 10a in the circumferential wall near the upper end of a pipe whose upper end is closed. Change all susceptors 6
The setting is such that raw material gas can be uniformly supplied to the target area.

In the apparatus of the present invention configured as described above, the wafer 7 is placed on each susceptor 6, and in this state, each susceptor 6 is mounted by inserting both side edges into the groove 5c of the pedestal 5. . A motor (not shown) is driven to rotate the rotary plate 4 around its axis 4a, and the main heater 8 and auxiliary heater 9 are driven to heat the susceptor 6 and wafer 7 to a predetermined temperature.

Water is passed through the water cooling pipe 3b of the water cooling jacket 3, and cooling gas such as nitrogen is passed through the inlet 3c into the passage 3d to keep the bell gear 2 cool. When the susceptor 6 and wafer 7 are heated to a predetermined temperature, raw material gas is supplied into the bell gear 2 from the air supply pipe 10. The raw material gas is made to flow between the stacked susceptors 6 from the air supply pipes 10 having different heights, and an epitaxial film is grown on the wafer 7 in a vapor phase.

Therefore, in the apparatus of the present invention constructed as described above, a large number of susceptors 6 can be stacked and arranged between each mount 5, and a wafer 7 can be placed on each susceptor 6 at the same time. Uniform epitaxial growth can be performed on a large number of wafers 7, and work efficiency is greatly improved. In addition, a large number of susceptors 6 are arranged in multiple stages, and a main heater 8 and an auxiliary heater 9 are arranged, so that both Control enables uniform heating of the wafer, yields a homogeneous epitaxial film, and improves film quality.
It can be easily attached to and detached from the stand, which improves work efficiency.

The device of the present invention has an outer diameter of 800 mm and a height of 500 mm.
For the size of 6 inch diameter wafers at once
It was confirmed that it is possible to epitaxially grow approximately 100 to 500 sheets.

It was also confirmed that vapor phase growth is more effective when carried out under a reduced pressure of about 50 Torr to 600 Torr.

FIG. 3 is a schematic diagram showing a part of the structure inside the bell gear showing another embodiment of the present invention, and is a peripheral portion on the rotary plate similar to that shown in FIGS. 1 to 3, and A pillar 15, which is a pedestal, is made of a heat-resistant material such as silicon carbide and has a rectangular cross section and a number of horizontal grooves 15a formed on one side at four locations in the circumferential direction. A large number of annular susceptors 16 are stacked upright toward the center of rotation of the susceptors 15 so as to span the plurality of support columns 15, and a wafer 17 is placed on each susceptor 16. The configurations of the main heater, auxiliary heater, raw material gas supply pipe, rotary plate, bell gear, etc. are substantially the same as those in the embodiment shown in FIGS. 1 to 3, and their explanation will be omitted.

In addition to the effects of the embodiments shown in FIGS. 1 to 3, the present invention has the advantage of increasing the susceptor area, reducing the number of susceptors, making handling easier, and simplifying the configuration. It will be done.

Although each of the above-mentioned embodiments has shown a configuration in which the present invention is applied to an epitaxial growth apparatus, the present invention is not limited to this in any way; for example, various CVD ( C
Needless to say, it can also be applied to hemical V apor D epospition).

〔effect〕

As described above, in the apparatus of the present invention, a large number of susceptors can be stacked, the number of wafers that can be processed at one time is greatly increased, work efficiency is improved, and radiation is emitted by stacking the susceptors together. The present invention has excellent effects, such as increasing the uniform heating effect and making the film thickness uniform in the circumferential and radial directions of the wafer, thereby improving quality.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of the apparatus of the present invention, FIG. 2 is a vertical cross-sectional view taken along the line - in FIG. 1, and FIG. 3 is a partial perspective view showing the structure inside the bell gear of another embodiment of the present invention. , 4 and 5 are schematic longitudinal sectional views of the conventional device. DESCRIPTION OF SYMBOLS 1...Base, 2...Belgear, 3...Water cooling jacket, 4...Rotary plate, 4a...Shaft part, 5... Frame, 5a...Sectoral part, 5c...Concave groove, 6...Susceptor , 7... wafer, 8... main heater, 9...
Auxiliary heater, 10... Air supply pipe, 10a... Air outlet, 15... Strut, 17... Susceptor.

Claims (1)

[Scope of Claims] 1. A plurality of susceptors formed in an annular shape or arranged in an annular manner on a horizontal rotary plate installed in a bell gear are mutually connected using a frame erected on the horizontal rotary plate. In a vapor phase growth apparatus in which semiconductor wafers can be placed on the upper surface of each susceptor by arranging the susceptors in multiple stages with a required interval between the susceptors, A vapor phase growth method characterized in that a heater is disposed around the periphery of the susceptor, and a plurality of air supply pipes facing the rotating range of the inner circumference of the susceptor and having different source gas blowing height positions are disposed. Device.