JPS6186498A - Gas phase growth apparatus - Google Patents

Abstract

PURPOSE:To form the broad gas flow and to make the film thickness of gas phase growth uniform by providing plural nozzles for feeding gas to the end part side of a susceptor and making the directions of gas injection of the nozzle holes different. CONSTITUTION:A barrel type susceptor assembly body 11 is fitted to a rotary axis 13 lengthened upward by perforating a base plate 16. Plural nozzles 18A for feeding the reaction gas are provided to one end part side of the susceptor 11. Every nozzle holes 36 of these nozzles 18A are slantingly provided in such shape that they are mutually faced. Thereby two reaction gas flow in ected from the nozzle holes 36 are allowed to collide against each other in the position close to the upper part of the surface of the susceptor assembly body 11 and the broad gas flow directed downward is formed. By this mechanism, the film thickness of gas phase growth for many wafers fitted on the susceptor 11 is made uniform and the velocity of gas phase growth is accelerated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to which the Invention Pertains] The present invention relates to a barrel-type vapor phase growth apparatus for performing pure vapor phase deposition of silicon crystal onto a semiconductor material substrate (hereinafter referred to as a wafer) such as silicon.

[Prior Art 9-i] A conventional barrel-type vapor phase growth apparatus has a nozzle provided at one end of a susceptor to supply a reaction gas along the rotation axis t of the susceptor. In this case the flow of reactant gas n
The flow becomes striped and almost laminar, and the reaction gas does not come into active contact with the wafer, resulting in slow growth.
Because of the striped flow, there was a drawback that the film thickness of the vapor phase was not uniform.

[Purpose of the invention]

The present invention completely eliminates these drawbacks, and its purpose is to
Reactant gas is applied to a large number of wafers attached to a susceptor.
The film thickness K of vapor phase growth is
It is an object of the present invention to provide an apparatus that can uniformly form a high-strength vapor phase growth layer of high quality efficiently.

[Rest of invention]

In the vapor phase growth apparatus of the present invention, a plurality of nozzles for supplying a reaction gas are arranged on one end side of the susceptor, and the nozzle holes of the nozzles are arranged on the surface of the susceptor. It is characterized in that the directions of gas ejection are set at different angles with respect to the moving direction of the susceptor.

[Embodiments of the invention]

A diagram showing an embodiment of the present invention will be described below. In FIG. 1, the susceptor assembly 11 has a plurality of strip-shaped susceptors arranged in a polygonal shape, and has a carefully sloped top surface and a lid-like body on the bottom surface. 9. A large number of wafers 12 are attached to its outer circumference. The susceptor assembly 11 is made of a hollow rotating shaft made of non-metallic material such as ceramics fixed to the upper and lower lid-like bodies, and is designed to rotate in both directions. It is completely covered by Belljar 14.

Below the bell jar 4, there is a cylindrical body 15 made of quartz that is concentric with the susceptor assembly 4 and has a small gap in close proximity thereto that does not hinder the rotation of the susceptor assembly 11. Both the bell jar 14 and the cylindrical body 15 are made of stainless steel. The base plates 16 are placed in close contact with each other and layered. The cylindrical body 15 is assembled into a susceptor assembly, and the belljar 14 and the susceptor assembly 11 are assembled together.
The space formed in the cylindrical body 5 is called a reaction chamber, and the rotating shaft 13 passes through the base plate 16 in an airtight manner. A quartz ring 19A is laid between the lower inner periphery of the bell jar 14 and the lower outer periphery of the cylindrical body 15. spray plate 1
6 is provided with a narrow hole 19B for discharging gas from the reaction chamber to the outside.

At the center of the rotation @ 13, a double pipe of a fixed inner pipe 17 and an outer pipe 18 is provided, and N2 or H2 gas flows upward from the inner pipe 17, and the outer pipe 18 has a plurality of fixed pipes at its upper end. (
The details of the flow of the reactant gas will be described later.

The lower outer periphery of the bell jar] 4 is an exhaust duct 21 that surrounds this and opens only the bell jar 1aljllll to the base 2 (1), which is placed on the outer periphery of the base grate 16.
is provided, and this exhaust pipe is connected to an exhaust pipe 22 shown in FIG. 2V. A lamp house 24 having a large number of lamps 23 is arranged on the exhaust duct 21, surrounding the bell jar 14, as shown in FIG.

A cooling fluid supply section 25 is formed on the back surface 4411 of the lamp house 24, and cooling fresh air is blown from a blower or cooler (not shown) into the kl/frDj fluid supply section 25 to cool the cooling air. It is supposed to be done.

A lifting and lowering mechanism (428) is provided adjacent to the μ exhaust duct 21Vc on the base 20.
9 is fixed, and the tip of the arm 29 removably grips a gripping part 31 fixed to the top of the gripping tool 3 Otic upper jibber jar 140. Also, the tip of the arm 29 is attached to the gripper 32 with an edge 1.
3. A cooling fluid supply section 33 is attached. The lower end of the B cooling fluid supply section 33 is placed on the upper surface of the lamp house 24, and the inner wall 34 has a large number of holes 35, so that cooling air is supplied to the bell jar 14 in the same way as the A cooling fluid supply section 25. sprayed onto the top of the Here Bellja 14 and B
Since the cooling fluid supply section 33 is attached to the arm 29, it can be raised and lowered at the same time, and once the lower surface of the bell jar 14 has risen above the nozzle 18A, the arm 29 must be rotated. When the cooling fluid supply section 33 is turned laterally, the ends A and B are rotatably connected to each other, and the lower center is separated, as shown by the dotted line in the figure. It can be moved to any position.

The cooling air blown out from the cooling fluid supply section 25 is sent to the outer periphery of the bell jar 14 and the lamp 2.
3 descends while being cooled, enters an exhaust duct 21, and is then forcibly discharged to the outside through an exhaust pipe 22 shown above. In this example, eight nozzles 18Ai-4 through which the reaction gas flows are provided radially, as shown in Figure 1, and there is one downward hole 36 (see Figure 1) near the tip. As shown in the figure, two of the eight nozzles 11'lA are arranged as a set, and the third nozzle hole 36p is provided at an angle facing each other, so that the flows of the two ejected reaction gases are directed to the susceptor. Assembly] Collision occurs at a position near the upper side of the surface of 1 to form a downward wide gas R.

Next, the operation of the embodiment described above will be explained. Lifting mechanism 2
8, the belljar 14 and the B cooling fluid supply section 33 are raised, and then the lamp jar 24 is lowered to the position shown in FIG. In this state, N2 gas is jetted out from the inner tube 17 and outer tube 18 to purge the air, and after the air purge is completed,
The H2 gas is then purged of the N2 gas, and then heated by the lamp 23. When the heating process reaches a predetermined temperature, the reaction gas such as silane is ejected from the outer tube 18 and the nozzle 18A together with N2 gas to perform vapor phase growth. Because they face each other, the reaction gas ejected from each nozzle hole 36 flows between the susceptor assembly 1 and the bell jar 1.
The collision near the upper part of the space between the wafer 12 and the wafer 12 generates a wide downward gas flow, which uniformly contacts the entire wafer 12, and the movement of the reaction gas becomes active, increasing the strength of the contact. Formation of a vapor phase growth layer is promoted.

At this time, N2 gas is directly jetted from the inner tube 17 to fill the upper space of the bell jar 14 with N2 gas, thereby cooling the upper wall surface of the bell jar 14 and preventing reaction scum from coming into contact with the upper wall surface. These gases are discharged from hole 19B of base grade 6. At this time, since the cylindrical body L 15 exists between the susceptor assembly 1=4 and the base plate 16, the gas may flow around the susceptor assembly ≠ the lower part of the husk and kick up dust, or the gas flow inside the belljar 14 may be Do not disturb (smoothly discharged. Lamp 23
The cooling air from the blower and cooler is simultaneously heated by the holes 26 of the A and B cooling fluid supplies 25 and 33.
The air is blown through the bell jar 14 and the lamp 23 through 35, cools the lamp 23 and the bell jar 14, descends along the bell jar 14, and is forcibly exhausted from the exhaust duct 21 to the exhaust pipe 22. . This air volume depends on the size of the quartz bell jar] 4, but it ranges from several 10-7 to several 1 nOi/
Although the exhaust duct 21 is extremely large in size, the belljar 1
Since the circumference is thick surrounding the lower part of the exhaust pipe 22, the exhaust resistance is small and suction from the exhaust pipe 22 allows smooth exhaust.

After vapor phase growth has been performed for a certain period of time, the lamp 23f is turned off to stop heating, and the wafer 12 is cooled through a 14ft bell jar while purging the reaction gas by blowing out only N2 gas from both tubes 17 and 18. Then, the N2 gas was stopped and the N2 gas was spouted out.
Turn the inside into N2 gas. Finally, the bell jar] 4 etc. is raised through the elevating mechanism 28, and the Lampnous 24
When the wafer 12 is opened and the wafer 12 is taken out, the series of vapor phase growth operations is completed. If it is necessary to clean the bell jar 14, after raising the bell jar 14, turn it to the side using the lifting/lowering/rotating mechanism 28, then lower it and place it on a stand (not shown). Remove from the gripper 30 and clean.

In the embodiment described above, the holes 36 of two adjacent nozzles 18A are inclined so as to face each other.
Various combinations are possible, such as forming a pair of three nozzles 18Alt with the central nozzle hole 36 facing downward.

〔Effect of the invention〕

As explained above, the vapor phase growth apparatus of the present invention has a barrel-shaped rod guard or susceptor, which is attached to a rotating shaft that extends upward through a base plate, and has a plurality of reactor gas supply ports on one end side. The nozzles of these nozzles were arranged so that their nozzle holes were approximately along the surface of the susceptor, and their gas ejection directions were set at different angles with respect to the direction of the susceptor.

With this configuration, the reaction gas ejected from the nozzle holes collides with and mixes with a large number of wafers attached to the susceptor, forming a wide gas flow, which makes the film thickness of the vapor phase growth uniform and increases the growth rate. has the advantage of being promoted.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a sectional view, FIG. 2 is a sectional view taken along the line 2--2 in FIG. 1, and FIG. 3 is a partially enlarged cross-sectional view of a nozzle hole. 1]...Susceptor assembly, 12...Unino 1.13
... Rotating shelf, ]4... Bell jar, 15... Cylindrical body, 16... Base plate, 17... Inner tube, 18...
...Outer tube, 18A...Nozzle, 23...Lamp, 2
4...U/Jino1us, 25.33...Cooling fluid supply section, 28...Elevating/lowering and rotating mechanism, 36...Nozzle hole.

Claims (1)

[Claims] 1. In a vapor phase growth apparatus having a barrel-shaped susceptor, a plurality of nozzles for supplying a reaction gas are arranged on one end side of the susceptor, and the nozzle holes of the nozzles are arranged approximately on the surface of the susceptor. A vapor phase growth apparatus characterized in that the directions of gas ejection are set at different angles with respect to the axial direction of the susceptor. 2. The vapor phase growth apparatus according to claim 1, wherein two adjacent nozzle holes form pairs and are opened at an angle toward opposite sides.