JPS6359529B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid phase epitaxial growth apparatus. The following will explain the case of liquid phase epitaxial growth of a - group compound semiconductor, particularly gallium aluminum arsenic (GaAlAs), as an example.

Liquid phase epitaxial growth is an important technology for semiconductor devices using - group compound semiconductors, such as light emitting diodes and solar cells.

FIG. 1 is a plan view showing a conventional boat for liquid phase epitaxial growth, FIG. 2 is a sectional view taken along the line --- in FIG. 1, and FIG. 3 is a sectional view taken along the -- line in FIG. This boat 1 is divided into an upper chamber 2, a middle chamber 3, and a lower chamber 4.
The middle chamber 3 is partitioned by a first slider 5, and a hole 6 is provided in a part of the first slider 5, and a hook 7 is provided in one end. A substrate holder 8 is provided in the middle chamber 3,
A substrate 9 is held on which crystals are to be epitaxially grown. It is partitioned into a middle chamber 3, a lower chamber 4, and a second slider 10, and the second slider 10 is provided with a hole 11 corresponding to the hole 6 of the first slider 5. A slideable melt storage box 12 is inserted into the lower chamber 4.

In this conventional boat 1, in the state shown in the figure, a saturated Ga melt 13 is stored in the upper chamber 2, and then the first slider 5 is pulled to the right in the figure to open the hole 6 in the upper chamber 2. and the middle chamber 3, and the saturated Ga melt 13 is introduced into the substrate holder 8 through the hole 6 to perform liquid phase epitaxial growth on the substrate 9.

At this stage, the catch 7 provided on the first slider 5 is configured not to come into contact with the end of the second slider 10 yet. When the liquid phase epitaxial growth is completed, the first slider 5
When further moved to the right in the figure, the second slider 10 is moved together by the catch 7, and the hole 11 is located between the middle chamber 3 and the lower chamber 4. The saturated Ga melt 13 that has been used for liquid phase epitaxial growth is stored in the melt storage box 12 in the lower chamber 4 through the hole 11.

Using such a boat, the mass productivity of liquid phase epitaxial growth has improved, but in the conventional boat structure shown in Figure 1, saturated Ga melt is stored in the upper chamber at the initial stage of boat operation. As a result, the center of gravity of the boat is high and unstable, requiring skill to operate the boat. In addition, the boat has a three-tier structure, and considering the amount of saturated Ga melt to be accommodated in the upper chamber and the length of the slider, there are significant restrictions on the size and number of substrates to be grown by liquid phase epitaxial growth. There was a drawback to receiving it.

This invention was made in view of the above points, and provides an apparatus that is easy to operate without the risk of tipping over, and that can perform liquid phase epitaxial growth on a large number of large-area substrates at the same time. is intended to provide.

FIG. 4 is a plan view showing an embodiment of the present invention, and FIG. 5 is a sectional view taken along the line V--V in FIG. 4. 21
22 is a melt storage chamber, 23 is a saturated Ga melt contained therein, and 24 is adjacent to the melt storage chamber 22 in the direction of arrow A. A slidably provided substrate holder; 25 is a substrate held by the substrate holder 24; 26 is a partition between the melt storage chamber 22 and the substrate holder 24; The partition plate 28 is configured to be rotatable only toward the side 22 and is closed by the hydraulic pressure of the saturated Ga melt 23. The partition plate 28 forms the bottom of the melt storage chamber 22 and passes under the substrate holder 24. 29 is a hole provided in a part of the slider 28; 30 is a small hole provided in a portion of the slider 28 that is hidden by the substrate holder 24; Holder 24
32 is a pin attached to the substrate holder 24 so as to be movable up and down; 33 is provided below the slider 28 of the boat body 21; This is a used melt storage box.

In this embodiment, a slider 2 is attached to the boat body 21.
8 to close the bottom of the melt storage chamber 22. next
A saturated Ga melt 23 consisting of Ga melt, GaAs, aluminum (Al), and zinc (Zn) is transferred to the melt storage chamber 22.
to be accommodated. In this state, the partition plate 26 is closed by the pressure of the saturated Ga melt 23, and the saturated Ga melt 23 does not leak out. Next, after installing the "slatted" board 31 and the board 25 on the board holder 24, this is attached to the boat body 21. Then pin 32
Insert. The used melt storage box 33 is installed in advance.

The boat body 21 prepared in this manner is placed in a growth furnace, and when the boat is equilibrated at a predetermined temperature, the substrate holder 24 is slid in the direction of arrow A in the figure. As a result, the substrate holder 24 pushes and rotates the partition plate 26 and enters the melt storage chamber 22 . and saturation
The Ga melt 23 passes through the "slatted" plate 31 and enters the substrate holder 24 cleanly. Then, the pin 32 is inserted into the hole 30 to connect the substrate holder 24 and the slider 28.

In this state, the growth furnace is gradually cooled to perform epitaxial growth. When the temperature drops to a predetermined temperature, the slider 28 is moved together with the substrate holder 24 by sliding it in the direction opposite to the arrow A in the figure, and the hole 29 is placed at the bottom of the melt storage chamber 22 in communication with the substrate holder 24. The saturated Ga melt 23 is stored in the melt storage box 33 after use. Note that since the bottom surface of the substrate holder 24 is sloped, saturation may occur.
The Ga melt 23 is reliably and quickly discharged.
Since the used melt storage box 33 stores the melt after use, there is no need to consider the temperature, and the height may be lowered and the length may be increased. Therefore, the height of the entire boat body 21 can also be reduced.

In the above embodiments, - group compound semiconductors, especially
Although the liquid phase epitaxial growth of GaAlAs has been described as an example, the present invention can also be applied to the liquid phase epitaxial growth of other general crystals.

As explained above, the liquid phase epitaxial growth apparatus according to the present invention has a two-stage structure, upper and lower, and the lower stage only contains a box for storing the used melt, so the height can be reduced. The apparatus is capable of accommodating many large substrates on which crystals are to be grown without fear of tipping over, and can easily grow crystals on a large number of substrates in a single growth operation.

[Brief explanation of drawings]

Fig. 1 is a plan view showing a conventional liquid phase epitaxial growth boat, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 2, and Fig. 4 is a sectional view taken along the - line in Fig. 2. The figure is a plan view showing an embodiment of the present invention, and FIG. 5 is a sectional view taken along the line -- in FIG. In the figure, 21 is the boat body (device body);
22 is a melt storage chamber, 23 is a saturated Ga melt (saturated crystal melt), 24 is a substrate holder, 25 is a substrate, 26
is a partition plate, 28 is a slider (slide plate), 29
30 is a hole, 32 is a pin [30 and 32 constitute a coupling means], and 33 is a used melt storage box.

Claims (1)

[Claims] 1. The main body of the device is divided into upper and lower parts by a slidable slide plate, and the upper part is provided with a storage chamber for the saturated crystal melt and can only be opened in the direction of this storage chamber. A substrate holder for holding a substrate on which crystals are to be grown is slidably disposed in a position partitioned by a partition plate, and a used melt storage box is disposed in the lower part of the storage chamber. The substrate holder holding the substrate in a state containing the saturated crystal melt is pushed open the partition plate and slid into the storage chamber, and after epitaxially growing crystals on the substrate, Slide the substrate holder together with the slide plate in a direction in which the substrate holder exits the storage chamber, and position the hole provided in the slide plate below the storage chamber to saturate the area in the storage chamber. A liquid phase epitaxial growth apparatus characterized in that the crystal melt is configured to be stored in the used melt storage box through the hole. 2. The liquid phase epitaxial growth apparatus according to claim 1, wherein the substrate holder has a bottom surface that is sloped to facilitate outflow of the saturated crystal melt. 3. Claims 1 or 2 further comprising a coupling means for coupling the substrate holder and the slide plate in that state when the substrate holder is slid into the storage chamber. The liquid phase epitaxial growth apparatus described in 2.