JPH02243588A - Crystal growth device - Google Patents

Abstract

PURPOSE:To suppress formation of compound of plural raw materials on the surface of other materials and to grow crystal in good reproducibility in a crystal growth device of carrying out crystal growth by using plural materials and by deposition method by equipping a trap mechanism to catch vapor of the materials in a crucible. CONSTITUTION:An inner pipe 12 is set in a crucible 11, a first material 21 (e.g. zinc) is stored at the outside of the inner pipe 12, a second material (e.g. selenium) is stored in the inner pipe and a trap mechanism 20 is equipped in the crucible 11. The first material 21 and a second material 22 are heated to different temperatures by a heater 15 to evolve vapors. Consequently, the vapor of the first material 21 is passed through the trap mechanism 20, reached to a substrate, the vapor of the second material 22 is directly reached to the substrate 17 to grow crystal. Then even if part of the vapor of the second material 22 flows into the trap mechanism 20, the part is retained in the interior thereof for >= a given period of time and reacted with the vapor of the first material 21 so that the vapor of the second material 22 will not reach the surface of the first material 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a crystal growth apparatus, and more particularly to a crystal growth apparatus that performs crystal growth by depositing vapor generated by heating a plurality of materials onto a substrate.

Crystal growth equipment such as hot wall epitaxial equipment that grows crystals by vapor deposition heats multiple materials at predetermined temperatures to generate steam, which is then deposited on a substrate, so that the generation of steam is not hindered. This is necessary from the point of view of reproducible crystal growth.

[Conventional technology]

FIG. 6 shows a cross-sectional view of an example of a conventional crystal growth apparatus. In the figure, 11 is a crucible, and an inner tube 12 is provided inside. The inner tube 12 has an opening 1 at one end on the opening side of the crucible 11.
2a, and the other end is sealed. A first material 13 is housed outside an inner tube 12 in the crucible 11, and a second material 14 is housed inside the inner tube 12.

A heater 15 is provided outside the crucible 11, which allows the first and second materials 13 and 14 to pass through the crucible 11.
It is configured to heat the A substrate 17 is placed on the substrate stand 16 above the opening of the crucible 11. The surface of the substrate 17 on which the crystal is to be grown faces the crucible 11 through the opening 16a of the substrate table 16. Crucible 1
1 and the entire substrate 17 are kept in a vacuum.

In the crystal growth apparatus having such a configuration, the heater 15
The first material 13 and the second material 14, each heated at a different temperature, generate steam, and this steam flows into the crucible 11.
and the opening 16a of the substrate table 16 to reach the surface of the substrate 17, where the surface of the substrate 17 is deposited and crystal growth is performed.

[Problem to be solved by the invention]

However, a part of the steam generated by heating the second material 14 and taken out from the opening 12a descends and reaches the surface of the first material 13, where it is combined with the first material F113. Put it away.

Therefore, the surface of the first material 13 is covered with the compound,
Evaporation of the first material 13 is hindered, and the amount of evaporation gradually decreases. Therefore, conventionally the first and second materials 13
There was a problem that the amount of evaporation could not be controlled using the temperature of 1 and 14 as an index, and crystal growth could not be performed with reproducibility.

The present invention has been made in view of the above points, and an object of the present invention is to provide a crystal growth apparatus that can prevent mixing or adhesion between a plurality of materials and can perform crystal growth with reproducibility.

[Means to solve the problem]

The crystal growth apparatus of the present invention heats multiple materials in a crucible at different temperatures to generate vapors of the multiple materials, and allows the vapors to reach a substrate to grow crystals on the substrate. In this device, a trap mechanism is provided inside the crucible.

This trap mechanism traps the vapors of the plurality of materials therein for a predetermined period or longer and combines them.

[Effect]

The trap mechanism is provided on the path of at least one of the plurality of vapors generated by heating each of the plurality of materials to the substrate, and other vapors are combined with the one vapor inside the trap mechanism. , the compound adheres to the trapping mechanism or the walls of the crucible.

Therefore, the trap mechanism can prevent other vapors from reaching the surface of the material that generates the one vapor.

〔Example〕

FIG. 1 shows a sectional view of a first embodiment of the invention.

In the figure, the same components as those in FIG. 6 are denoted by the same reference numerals, and the explanation thereof will be omitted. In FIG. 1, 20 is a trap mechanism whose central through hole is inserted into the inner tube 12.

Moreover, 21 is zinc (Zo) as a first material accommodated in the crucible 11 outside the inner tube 12. 22 is selenium (S, ) as a second material housed inside the inner tube 12.

Since S8 has a higher vapor pressure than 2°, the heating temperature for generating steam needs to be lower than that of Zn, so S8 of the second material 22 is heated toward the inside of the inner tube 12. be accommodated.

FIG. 2 shows the external appearance of the trap mechanism 20 shown in FIG. 1. In the figure, 23, 24, and 25 are quartz disks having the same diameter, and the center portions of these disks are connected at equal intervals. The disk 23 has small diameter through holes 23a and 23b.
are bored at positions facing each other. Similarly,
The disk 24 has 24a and 24b, and the disk 25 has 25a.
Two small-diameter through holes are bored, indicated by 25b and 25b, respectively.

The above-mentioned through holes 23a, 23b,! =24a, 24b and 2
The distances of 5a and 25b from the tube 26 are made different from each other as shown in FIG. This is for the same reason as the reason why the disc 24 is provided as a partition, and is to prevent steam from flowing into the trap mechanism 20 from the outside for as long as possible. The length in the longitudinal direction of the cylinder 26 of this trap mechanism 20 is, for example, about 1 (: l to 5 m).

Next, the operation of the trap mechanism 20 will be explained with reference to the enlarged sectional view of FIG. 1 shown in FIG. 3.

In FIG. 3, the same components as in FIGS. 1 and 2 are designated by the same reference numerals, and their explanations will be omitted.

In FIG. 3, the first vapor obtained by heating the zinc 21 passes through the through holes 25b → 24b → 23b in this order, and at the same time passes through the through holes 25a → 24a → 23a in the order of the substrate 17. reach. Further, the second vapor obtained by heating the selenium 22 is transferred to the substrate 1 from the opening 12a of the inner tube 12.
Reach in 7 directions.

As a result, the first and second
Crystal growth of zoS8 is performed by vapor deposition of . Note that at this time, the substrate 17 is also heated by a heater (f, not shown) located above.

On the other hand, a portion of the second vapor descends and passes through, for example, the through hole 23b, as shown by B in FIG.
flows into the interior of. However, inside the trap mechanism 20, as shown by A in the same figure, there is first steam that passes sequentially through the through holes 25b and 24b and reaches the through hole 23b. 2 steam trap mechanism 2
0 and the compound adheres to the trap mechanism 20 or the wall of the crucible 11.

Since the partition disk 24 retains the second vapor in the trap mechanism 20 for a long time, it is possible to increase the probability that it will combine with the first vapor. However, since the amount of this second vapor is not so large, the Z, S,
does not interfere with crystal growth.

As a result, the second vapor is trapped by the trap mechanism 20 before reaching the surface of the zinc 21.
Generation of znS8 on the surface can be suppressed. Therefore, zinc 21. It becomes possible to control the amount of evaporation using the temperature of selenium 22 as an index, and crystal growth can be performed with reproducibility.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a sectional view of a second embodiment of the present invention, in which the same components as those in FIG.

In FIG. 4, reference numeral 30 denotes a trap mechanism, which is provided at the upper part of the inner tube 12.

Further, 31 is a first material, and 32 is a second material.

The trap mechanism 30 has through holes 30a, 30b, and 30c, and the second steam generated by heating the second material 32 in the inner tube 12 flows through these through holes 30a-+30c.
, 30b-+30c, and reach the surface of the substrate 17. On the other hand, the first vapor generated by heating the first material 31 passes through the opening of the crucible 11 and reaches the surface of the substrate 17 .

Here, the first steam enters the inner pipe 12 and the second steam enters the inner pipe 12.
Even if an attempt is made to generate a compound on the surface of the material 32, the trap mechanism 30 causes the first vapor to be combined with the second vapor from the inner pipe 12 inside the trap mechanism 30. It almost never reaches the surface of 32. Therefore, in this embodiment, compounds generated on the surface of the second material 32 can be suppressed, and crystal growth can be performed on the surface of the substrate 17 with reproducibility.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a sectional view of a third embodiment of the present invention, in which the same components as those in FIG. 4 are designated by the same reference numerals, and their explanation will be omitted.

In FIG. 5, reference numeral 35 denotes a trap mechanism, which is constituted by a spiral or other conduit provided above the opening 12a of the inner tube 12.

According to this embodiment, the second
The steam travels up the pipe line of trap machine #t35 over a long period of time, and reaches the surface of the substrate 17 through the terminal opening of the pipe line. Here, a part of the first steam is transferred to the trap mechanism 3
5, the trap mechanism 35 has a long pipe length and can be retained therein for a long period of time, increasing the probability that it will combine with a portion of the second vapor. Therefore, this embodiment also has the same effects as the second embodiment.

(Effects of the Invention) As described above, according to the present invention, vapors of a plurality of materials can be combined inside the trap mechanism, so generation of compounds on the surfaces of other materials of the plurality of materials can be suppressed. This makes it possible to perform reproducible crystal growth on the substrate using the temperature of multiple materials as an index, and the crucible with the same source can be used for multiple crystal growths, which is effective in reducing overall costs. It has the following features.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention, FIG. 2 is a perspective view of an embodiment of the trap mechanism, FIG. 3 is an enlarged sectional view of the main part of FIG. 1, and FIGS. The figures are sectional views of second and third embodiments of the present invention, respectively, and FIG. 6 is a sectional view of an example of a conventional device. In the figure, 11 is a crucible, 12 is an inner tube, 17 is a substrate, 20, 30, 35 is a trap mechanism, 21 is zinc (first material), 22 is selenium (second material), 31 is a first material Material: 32 indicates the second material. Closing of the gate (deer cross-section Fig. 1, Fig. 2, whistle Fig. 1, etc.), small cross-section, Fig. 4 (with 5 days of moon grass, 3P! On the other hand, W shell of the case, m) Figure No!: Top view of the second missing example of the Ming era.

Claims (1)

[Claims] A plurality of materials (21, 22, 31) in the crucible (11)
, 32) at different temperatures to prepare the plurality of materials (21, 32).
22, 31, 32), and the vapor is applied to the substrate (1).
7) In a crystal growth apparatus for growing crystals on the substrate (17), the plurality of materials (21, 22
, 31, 32) for a predetermined period of time or more to combine the vapors inside the crucible (11).