JPH04186823A - Vapor growth device - Google Patents

Abstract

PURPOSE:To reduce the dissipation of the heat of a susceptor to the side of a susceptor receiver, to make uniform a temperature distribution in the susceptor and to make it possible to vapor grow a good compound semiconductor thin film on a substrate by a method wherein the susceptor is supported attachably or detachably by the susceptor receiver in almost a linear contact or a point contact. CONSTITUTION:In a vapor growth device wherein a susceptor 4 for placing a substrate 3 and a susceptor receiver 5 for supporting attachably or detachably the susceptor 4 are arranged in a reaction tube 2, the substrate 3 placed on the susceptor 4 is heated by a heating means 6 and a thin film is vapor-phase grown on the substrate 3 with gas which is fed in the tube 2, the susceptor 4 is supported attachably or detachably by the receiver 5 in almost a linear contact or a point contact. For example, a groove part 5a is formed in the slant face-shaped inner peripheral surface of the upper part of a cylindrical susceptor receiver 5 consisting of molybdenum or the like and the outer peripheral surface of the susceptor 4 consisting of molybdenum or the like and the lower part of the outer peripheral surface are respectively supported attachably or detachably by protrusion parts 5b and 5c of the tips of the groove part 5a in a linear contact.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to a vapor phase growth apparatus used for manufacturing compound semiconductors and the like.

(Prior Art) A vapor phase growth apparatus for manufacturing a semiconductor or the like by vapor phase growing a crystalline thin film of a semiconductor or the like on a substrate is configured as shown in FIG. 7, for example.

As shown in this figure, in this vapor phase growth apparatus, a substrate 3 is placed in a reaction tube 2 that is hermetically fixed on a base plate 1.
a susceptor 4 on which the susceptor 4 is placed, a cylindrical susceptor receiver 5 that removably supports the susceptor 4, a heater 6 that heats the substrate 3 via the susceptor 4, and an electrode that supports the heater 6 and energizes the heater 6. 7 are arranged.

A supply port 2a for supplying gas (reactant gas, carrier gas, etc.) into the reaction tube 2 is formed in the upper part of the reaction tube 2, and a supply port 2a for supplying gas (reaction gas, carrier gas, etc.) into the reaction tube 2 is formed in the lower part of the reaction tube 2. An exhaust port 2b is formed for discharging the gas.

A step 5f is formed on the inner peripheral surface of the upper part of the susceptor receiver 5, and the susceptor 4 is detachably attached so that the entire outer peripheral surface and the lower part of the outer peripheral surface of the susceptor 4 are in contact with the step 5f. ing. Further, the heater 6 is disposed within a susceptor receiver 5 that supports the susceptor 4.

Although not shown in the figure, a cooling device for water-cooling the inner wall surface of the reaction tube 2 is provided on the outside of the reaction tube 2, and a cooling device for rotating the susceptor 4 is provided at the bottom of the susceptor receiver 5. Rotary drive device or connected.

The conventional vapor phase growth apparatus is configured as described above, in which the substrate 3 placed on the susceptor 4 is heated to a predetermined temperature by the heater 6, and the reaction tube 2 is supplied from the supply port 2a.
reaction gas (e.g. SiH4,5tH2Cl□,5
iHC1,,5iC14, etc.) with a carrier gas (e.g.
H2, etc.), and a thin film of a compound semiconductor is grown on the substrate 3 in a vapor phase.

(Problem to be Solved by the Invention) By the way, in the conventional vapor phase growth apparatus described above, the outer circumferential surface and the lower portion of the outer circumferential surface of the susceptor 4 are in surface contact with the stepped portion 5f formed on the inner circumferential surface of the upper part of the susceptor receiver 5. are in contact with each other.

Therefore, since the contact area between the susceptor 4 and the stepped portion 5f of the susceptor receiver 5 is large, the heat of the susceptor 4 heated by the heater 6 is considerably lost by conduction from the outer peripheral surface of the susceptor 4 to the susceptor receiver 5 side. . Therefore, since the temperature on the outer circumferential side of the susceptor 4 is lower than that on the center side, the temperature distribution becomes uneven (see Fig. 8), and the temperature of the substrate 3 placed on the susceptor 4 also becomes uneven. . Therefore, the thin film of the compound semiconductor grown on the substrate 3 in vapor phase becomes non-uniform, which causes problems such as variations in oscillation frequency, especially when such a thin film is used to fabricate a laser diode, for example.

The present invention was made for the purpose of solving the above-mentioned problems, and it reduces the heat of the susceptor heated by the heater escaping to the side of the susceptor receiver, and makes the temperature distribution of the susceptor uniform, thereby forming a good compound semiconductor on the substrate. The present invention aims to provide a vapor phase growth apparatus capable of vapor phase growth of thin films.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides a susceptor for placing a substrate in a reaction tube, and a susceptor receiver for detachably supporting the susceptor. In the vapor phase growth apparatus, the substrate mounted on the susceptor is heated by a heating means, and a thin film is vapor-phase grown on the substrate using gas supplied into the reaction tube. It is characterized by being removably supported by almost line contact or point contact.

(Function) According to the present invention, by detachably supporting the susceptor on the susceptor receiver through line contact or point contact, the contact area between the susceptor and the susceptor receiver is reduced, so that the heat of the susceptor escapes to the side of the susceptor receiver. can be reduced. Therefore, since the temperature drop on the outer peripheral side of the susceptor is reduced, the temperature distribution of the susceptor can be made approximately uniform, and a good compound semiconductor thin film can be grown on the substrate by vapor phase growth.

(Example) Hereinafter, the present invention will be explained in detail based on the illustrated example.

FIG. 1 is a sectional view showing a vapor phase growth apparatus according to the present invention. In addition, the same reference numerals are attached to the same members as in the conventional case for explanation.

As shown in this figure, a reaction tube 2 that is airtightly fixed on a base plate 1 includes a disk-shaped susceptor 4 made of molybdenum or the like on which a substrate 3 is placed, and a susceptor 4 that is detachably supported. A susceptor receiver 5 made of cylindrical molybdenum or the like, and a heater 6 that heats the substrate 3 via the susceptor 4.
An electrode 7 is disposed to support the heater 6 and to supply electricity to the heater 6.

A supply port 2a for supplying gas (reactant gas, carrier gas, etc.) into the reaction tube 2 is formed in the upper part of the reaction tube 2, and a supply port 2a for supplying gas (reaction gas, carrier gas, etc.) into the reaction tube 2 is formed in the lower part of the reaction tube 2. An exhaust port 2b is formed for discharging the gas.

A groove 5a is formed in the sloped inner peripheral surface of the upper part of the susceptor receiver 5, and protrusions 5b, 5 are formed at the tips of the groove 5a.
c, the outer circumferential surface and the lower portion of the outer circumferential surface of the susceptor 4 are removably supported in line contact.

The heater 6 is disposed below the susceptor 4 in the susceptor receiver 5, and is energized through an electrode 7 that supports the heater 6.

Also, although omitted in the figure, there is a reaction tube 2 on the outside of the reaction tube 2.
A cooling device for cooling the inner wall surface of the susceptor 4 with water is provided, and a rotation drive device for rotating the susceptor 4 is connected to the lower part of the susceptor receiver 5.

The vapor phase growth apparatus according to the present invention is configured as described above, and rotates the susceptor receiver 5 by driving the rotation drive device (not shown) to rotate the substrate 3 placed on the susceptor 4 (
For example, at a rotation speed of 10 rpm or more), the substrate 3
The susceptor 4 on which the SiH4
, SiH2Cl 2 , SiHCl 3 ,
S ICl 4 etc.) is supplied together with a carrier gas (eg H2 etc.) to grow a compound semiconductor thin film on the substrate 3 in a vapor phase.

At this time, the susceptor 4 is attached to the protrusions 5b and 5 of the susceptor receiver 5.
Since the susceptor 4 is supported in line contact with the susceptor 4, the conduction of the heat of the susceptor 4 heated by the heater 6 to the susceptor receiver 5 side is reduced, and the escape of the heat of the susceptor 4 to the susceptor receiver 5 side is significantly reduced. I can do something. Therefore, since the temperature drop on the outer peripheral side of the susceptor 4 is reduced, the temperature distribution of the susceptor 4 heated by the heater 6 becomes approximately uniform (see FIG. 8), and the temperature of the substrate 3 also becomes approximately uniform. Become. Therefore, a uniform and good compound semiconductor thin film can be grown in vapor phase over the entire surface of the substrate 3.

In this way, by making the temperature distribution of the susceptor 4 approximately uniform, it is possible to obtain a good compound semiconductor thin film. For example, by manufacturing a laser diode using this thin film, it is possible to produce a laser diode with no variation in oscillation frequency. A good laser diode can be obtained.

FIGS. 2 to 5 and 6 are a sectional view and a plan view, respectively, showing contact surfaces between a susceptor and a susceptor receiver according to other embodiments of the present invention.

In FIG.
a, and the upper part of the susceptor receiver 5 is inclined inward, so that the tip surface of the susceptor receiver 5 supports the stepped portion 4a formed on the outer circumferential surface of the susceptor 4 in line contact.

In FIG. 3, the susceptor 4 of the protrusion 5b and 5C at the tip of the groove 5a formed in the susceptor receiver 5 shown in FIG.
The area of the surface in line contact with the projections 5b and 5c is slightly increased.
It has a configuration in which a flat part is formed at the tip.

In FIG. 4, a groove 5a is formed on the inner peripheral surface of the upper part of the susceptor receiver 5, and protrusions 5b, 5 at the tip of the groove 5a are formed.
c, the susceptor 4 is supported in the same way as in the embodiment shown in FIG.
The susceptor 4 is supported by making point contact (at least three or more protrusions 5C are formed) with the lower part of the outer circumferential surface of the susceptor 4 at a plurality of points without extending over the entire circumference.

In addition, on the contrary, the protrusions 5b of the susceptor receiver 5 are brought into point contact with the outer peripheral surface of the susceptor 4 at multiple points, and the protrusions 5c of the susceptor receiver 5 are brought into line contact with the lower part of the outer peripheral surface of the susceptor 4. May be supported.

In FIG. 5, a separate susceptor receiver 8 made of, for example, ceramic or glass with low thermal conductivity is disposed above the conventional susceptor receiver 5 shown in FIG. The outer peripheral surface of the susceptor 4 and the lower part of the outer peripheral surface are supported in line contact by the projections 8b and 8c at the tip of the groove 8a formed in the upper part of the susceptor 4, and it is possible to further reduce the escape of heat from the susceptor 4. .

Further, a plurality of separate susceptor receivers 8 may be interposed between the susceptor 4 and the susceptor receiver 5.

In FIG. 6, a plurality of protrusions (three in the figure) 5e having a flat portion at the tip are formed on a stepped portion 5d formed on the inner circumferential surface of the susceptor receiver 5 on which the susceptor 5 is disposed, and these protrusions 5e supports the susceptor 5 in almost point contact.

In this case, by supporting the susceptor 4 with only point contact with the susceptor receiver 5, the heat of the susceptor 4 can be transferred to the susceptor receiver 5.
Heat conduction to the sides can be effectively reduced.

In this way, in each of the embodiments shown in FIGS. 2 to 6, as in the embodiment shown in FIG. 1, the conduction of heat from the susceptor 4 heated by the heater 6 to the susceptor receiver 5 side is reduced Therefore, the escape of heat from the susceptor 4 to the susceptor receiver 5 side is significantly reduced, and the temperature distribution of the susceptor 4 can be made uniform.

Furthermore, in each of the embodiments described above, by forming the susceptor receiver 5 from ceramics, glass, or the like having low thermal conductivity, it is possible to further reduce the escape of heat from the susceptor 4 to the susceptor receiver 5 side.

[Effects of the Invention] As described above in detail based on the embodiments, according to the present invention, the temperature distribution of the susceptor heated by the heater can be made approximately uniform, so that the entire surface of the substrate can be heated. A uniform and good compound semiconductor thin film can be grown by vapor phase growth.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a vapor phase growth apparatus according to the present invention, and FIGS. 2 to 5 and 6 respectively show contact surfaces between a susceptor and a susceptor receiver according to other embodiments of the present invention. FIG. 7 is a cross-sectional view showing a conventional vapor phase growth apparatus, and FIG. 8 is a diagram showing the temperature distribution of the susceptor of the present invention and the conventional vapor phase growth apparatus. 1... Base plate 2... Reaction tube 3... Substrate 4... Susceptor 5... Susceptor receiver 5a...
Groove portions 5b, 5c...Protrusion portion 6...Heater
7. Electrode

Claims (1)

[Claims] A susceptor for placing a substrate in a reaction tube and a susceptor receiver for detachably supporting the susceptor are provided, and the substrate placed on the susceptor is heated by a heating means and supplied into the reaction tube. A vapor phase growth apparatus for growing a thin film on the substrate using gas in a vapor phase, characterized in that the susceptor is detachably supported on the susceptor holder in substantially line contact or point contact.