JP3203428B2 - Substrate holder for liquid phase epitaxy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a substrate holder for liquid phase epitaxy, and more particularly to a slide board having a concave portion on its upper surface for accommodating a single crystal substrate such as GaAs or GaP on which liquid phase epitaxial growth of a III-V compound semiconductor is to be performed. The present invention relates to a substrate holder for liquid phase epitaxy of a liquid crystal type.

[0002]

2. Description of the Related Art Conventionally, this type of substrate holder for liquid phase epitaxy is formed by coating a part or all of the surface of a holder body such as graphite with a silicon carbide film (Japanese Patent Application Laid-Open No. 54-16816).
No. 5).

[0003]

However, in the above-mentioned conventional substrate holder for liquid phase epitaxy, a suitable binder is added to a powdery graphitizable carbon material such as coke and kneaded, and the kneaded material is formed. After firing,
Furthermore, the holder body is covered with a silicon carbide film to prevent the release of occluded gas from the holder body afterwards, thereby preventing the release of occluded gas from the holder body. The single crystal substrate is consumed by the occluded gas released from cracks in the silicon carbide film generated by repeated use under a cooling / heating cycle, or the single crystal substrate becomes uneven during the cooling process due to its relatively large thermal conductivity. There is a problem that the epitaxial layer becomes non-uniform due to cooling.

In addition, since the silicon carbide film is easily wetted by Ga as a solvent, it becomes difficult to remove the single crystal substrate after the epitaxial growth from the substrate holder, chipping or the like occurs on the single crystal substrate, The carbon particles dropped from the main body are caught in the epitaxial layer of the single crystal substrate and become defective, resulting in a decrease in yield.

Accordingly, an object of the present invention is to provide a substrate holder for liquid phase epitaxy which can make the quality of an epitaxial substrate uniform and can increase the yield.

[0006]

In order to solve the above problems, a substrate holder for liquid phase epitaxy according to the present invention comprises:
A substrate holder for liquid phase epitaxy for accommodating a single crystal substrate such as GaAs or GaP on which liquid phase epitaxial growth of a group V compound semiconductor is to be performed, wherein the impurity content is 5 pp.
m or less, and all the closed pores present are 50 μm or less.
It is made of only the glass-like carbon Ru bottom der.

Here, glassy carbon is obtained by firing and carbonizing a cured product of a liquid thermosetting resin in a non-oxidizing atmosphere, and has excellent gas impermeability, high hardness and no anisotropy. It is a carbon material having a three-dimensional network glass structure having a texture.

[0008]

In the above means, no occluded gas is released,
In addition, the thermal conductivity is relatively small, and only the glassy carbon having an impurity content of 5 ppm or less is used.
The non-wetting property with Ga, which is a catalyst such as s, P, and Al, is increased, and the generation of verticles is reduced.

The glassy carbon has an impurity content of 5 pp
If it exceeds m, the wettability with Ga, which is a solvent such as As, P, Al, etc., is improved, and at the same time, impurities are released. Also exist
If the size of all the closed pores exceeds 50 μm, occluded gas is likely to be generated.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram of a liquid phase epitaxy apparatus having a liquid phase epitaxy substrate holder according to one embodiment of the present invention.

[0011] The liquid-phase epitaxy for the substrate holder 1, the presence
All independent closed pores is only glassy carbon of high purity Ru der below 50 [mu] m (hereinafter impurity content 5 ppm), the single crystal substrate on the upper surface of the rectangular plate-shaped holder main body 2 3
A substrate accommodating recess 4 for accommodating the quartz rod 5 is provided.
Into and out of the furnace tube (not shown).

On the substrate holder 1, a rectangular flat slider 6 made of the same glassy carbon is slidably mounted by a quartz rod 7, and its slider body 8 is provided.
Is provided with a hole 10 for accommodating the GaP solution 9 and the like.

In manufacturing the substrate holder for liquid phase epitaxy having the above structure, first, a liquid thermosetting resin such as furan resin, phenol resin, epoxy resin, unsaturated polyester resin, urea resin, melamine resin, alkyd resin, After repeating the operation of adding the organic sulfonic acid little by little to the xylene resin and polymerizing at room temperature, and defoaming the polymerized fluid polymer, pour it into a mold and place it in the dryer, The temperature was slowly raised from 80 to 100 ° C. at a rate of 20 ° C./hr and kept at this temperature for 10 hours to obtain a rectangular resin plate.

Then, the resin plate is placed in a non-oxidizing atmosphere (an inert gas atmosphere such as helium, argon or nitrogen, a reducing gas atmosphere such as hydrogen or halogen, or an atmosphere under reduced pressure or vacuum or in a state where the atmosphere is shut off). 2 in
The temperature was raised to 1000 ° C. at a temperature rising rate of 3 ° C./hr, followed by firing and carbonization to obtain a three-dimensional network glass structure. A substrate holder for epitaxy was obtained.

When liquid phase epitaxial growth was performed on 100 GaAs single crystal substrates using the above-described substrate holder for liquid phase epitaxy, the number of occurrences of slip of the epitaxial layer, defective particles with particles such as carbon particles adhered, chipping defects, etc. Are as shown in Table 1 together with a case where a conventional substrate holder in which a graphite-based holder body is coated with a silicon carbide film is used.

[0016]

[Table 1]

Therefore, by using the substrate holder for liquid phase epitaxy of the present invention, the homogeneity of the epitaxial layer can be greatly improved, the generation of particles can be largely suppressed, and the generation of chipping and the like can be reduced. You can see that.

[0018]

As described above, according to the substrate holder for liquid phase epitaxy of the present invention, since no occluded gas is released and the thermal conductivity is relatively small as compared with the conventional one, the single-layer substrate holder is simple. The crystal substrate is not consumed by the occluded gas, the quality thereof can be improved, and the single crystal substrate is cooled uniformly in the cooling process, so that the epitaxial layer can be made uniform.

Further, since it is composed of only glassy carbon having an impurity content of 5 ppm or less, the non-wetting property with Ga as a solvent such as As, P, and Al is increased, and the generation of particles is reduced. The single crystal substrate on which the epitaxial growth has been completed can be easily taken out from the substrate holder without causing chipping or the like, and the contamination of the single crystal substrate can be reduced, and the durability can be increased. Yield can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a liquid phase epitaxy apparatus provided with a substrate holder for liquid phase epitaxy according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate holder 2 Holder main body 4 Substrate accommodation recess

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ritsuo Makita 378 Oguni-machi, Oguni-machi, Oguni-machi, Nishiokitama-gun, Yamagata Prefecture Inside the Oguni Plant, Toshiba Ceramics Co., Ltd. 378, Toshiba Ceramics Co., Ltd.Oguni Factory (72) Inventor Takashi Tanaka 378, Okunicho, Oguni-machi, Nishiokitama-gun, Yamagata Prefecture Toshiba Ceramics Co., Ltd.Oguni Factory (56) References (JP, A) JP-A-3-223196 (JP, A) JP-A-2-172887 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/208, 21 / 368 C30B 19/06

Claims (1)

(57) [Claims] 1. A liquid phase epitaxy substrate holder for accommodating a single crystal substrate such as GaAs or GaP on which liquid phase epitaxial growth of a III-V compound semiconductor is performed,
And at 5ppm or less impurity content, all independent closed liquid-phase epitaxy substrate holder holes is equal to or only one <br/> Ranaru glassy carbon Ru der below 50μm present.