JPH0260052B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This invention relates to an improvement in a liquid phase epitaxial crystal growth apparatus.

[Prior art]

BACKGROUND ART Mass production of liquid phase epitaxially grown crystal layers 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 the configuration of a conventional liquid phase epitaxial crystal growth apparatus used for such applications, and FIG. 2 is a cross-sectional view taken along the - line. In the figure, reference numeral 1 denotes the boat body, which has a three-stage structure: an upper chamber 2, a middle chamber 3, and a lower chamber 4.
5 is a drawer container inserted into the lower chamber 4, 6 is a first slider that partitions the upper chamber 2 and the middle chamber 3, and 7 is a second slider that partitions the middle chamber 3 and the lower chamber 4.
8 is a saturated gallium (Ga) melt contained in the upper chamber 2, 9 is a substrate placed in the middle chamber 3 on which epitaxial crystal growth is to be made, and 10 is a slider 6 in the first slider 6. aperture provided,
11 is an opening provided in the second slider 7; 12
is an L-shaped plate provided on the first slider 6, which moves the second slider 7 with a time delay when the first slider 6 is moved in the direction of the arrow shown in the figure. All of the above are made of carbon plates.

In this conventional apparatus, in the state shown in FIGS. 1 and 2, a substrate 9 is placed in the middle chamber 3, a saturated Ga melt 8 is stored in the upper chamber 2, and this boat is placed in a growth furnace. Increase temperature. After the boat reaches equilibrium at a predetermined temperature, when the first slider 6 is moved in the direction of the arrow, the aperture 10 comes to communicate between the upper chamber 2 and the middle chamber 3; through and saturated
The Ga melt 8 flows into the middle chamber 3 and immerses the substrate 9.
By slowly cooling the growth furnace in this state, epitaxial crystal growth is obtained on the substrate 9. During this epitaxial growth, the saturated Ga melt 8 is connected through the opening 10 into the upper chamber 2 and the middle chamber 3. After the epitaxial growth is completed, move the first slider 6 further in the direction of the arrow to L.
The second slider 7 is moved by the shape plate 12, the middle chamber 3 and the lower chamber 4 are communicated through the opening 11, and the saturated Ga melt 8 is allowed to flow into the drawer container 5.

In such a liquid phase epitaxial crystal growth apparatus, in order to make the surface of the epitaxially grown crystal mirror-like, the supersaturated portion of the saturated Ga melt 8 remaining in the upper chamber 2 is transferred to the first slider 6.
After separation, the saturated Ga in contact with the substrate 9
It is necessary to draw out only the melt and drop it into the container 5.

However, when trying to achieve this with the conventional device described above, the first slider 6 is moved greatly in the direction of the arrow, and the opening 10 comes out of the boat body 1, causing the upper chamber 2 and the middle chamber 3 to be connected. In order for the L-shaped plate 12 to move the second slider 7 only after the gap is cut off, the first slider 6 must be made extremely long, resulting in a large-sized device.

[Summary of the invention]

This invention was made in view of the above points, and after the epitaxial growth is completed, the opening provided in the first slider is closed by simply sliding the first slider a short distance, and the opening in the upper stage is closed. By cutting off the communication between the chamber and the middle chamber and allowing the second slider to slide in a dependent manner from this point on, it is possible to downsize the device, and if the device is the same size, the processing capacity will be reduced. The present invention provides a liquid phase epitaxial crystal growth apparatus with a large capacity.

[Embodiments of the invention]

FIG. 3 is a plan view showing the configuration of an embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along the - line. The same reference numerals as in the conventional example in FIGS. Avoid duplication of explanations. In this embodiment, a cover plate holding plate 13 is provided at the bottom of the upper chamber 2.
A cover plate 14 is held between this and the first slider 6. The cover plate 14 is dimensioned to enter into and close the first opening 10a provided in the first slider 6. Along with this, the first opening 10a corresponds to the opening 10 in the conventional example, but the lid plate 14
The shape is such that it will not fall out when inserted. Further, a second opening 15 is provided in the first slider 6 at a position below the cover plate holding plate 13 in the state shown in FIG. 4, and the first slider 6 is moved in the direction of the arrow. When the first opening 10a reaches the position where the upper chamber 2 and the middle chamber 3 are communicated with each other, the second opening 15 also comes out from under the cover plate retaining plate 13 and connects the upper chamber 2 and the middle chamber 3. Shares communication with room 3.
When the first opening 10a comes under the cover plate 14 and is closed, the second opening 15 is configured to come out of the boat body 1.

Now, the operation of this embodiment device is almost the same as that of the conventional example described above, but first, when the first slider 6 is moved in the direction of the arrow, the first opening 1 is opened as described above.
The upper chamber 2 and the middle chamber 3 communicate through 0a and the second opening 15, and the saturated Ga melt 8 contained in the upper chamber 2 flows into the middle chamber 3 and immerses the substrate 9 therein.
When the epitaxial crystal growth on the substrate 9 is completed by slow cooling, when the first slider 6 is further moved in the direction of the arrow, the first opening 10a is formed in the cover plate 1.
4, the cover plate 14 enters into this first opening 10a and closes it, and at this point, the second opening 15 has already come out of the boat body 1. , the upper chamber 2 of the saturated Ga melt 8
The supersaturated portion within is separated. Therefore, from then on, as the first slider 6 moves in the direction of the arrow, the second slider 7 is moved by the L-shaped plate 12, and the middle chamber 3 and the lower chamber 4 are separated by the opening 11. The saturated Ga melt 8 can be made to flow into the drawing container 5 by communicating with the saturated Ga melt 8. In this way, not only can an epitaxial crystal growth layer having a mirror surface be obtained on the substrate 9, but also the moving distance of the first slider 6 can be reduced.

Incidentally, in the above embodiment, epitaxial crystal growth using a Ga melt was exemplified, but it goes without saying that the present invention can also be used for the growth of other crystals.

〔Effect of the invention〕

As explained above, the liquid phase epitaxial crystal growth apparatus according to the present invention has a first slider that partitions the upper chamber and the middle chamber of the boat body, and a first slider that partitions the middle chamber and the lower chamber to perform epitaxial growth. A second slider is provided which slides subordinately to the first slider after completion of the operation, and the sliding distance of the first slider until the second slider is driven to slide is shortened, thereby reducing the size of the device. The processing capacity can be increased if the device is of the same size.

[Brief explanation of the drawing]

Figure 1 is a plan view showing the configuration of a conventional liquid phase epitaxial crystal growth apparatus, and Figure 2 is the same as in Figure 1.
3 is a plan view showing the configuration of an embodiment of the present invention, and FIG. 4 is a sectional view taken along the - line in FIG. 3. In the figure, 1 is the boat body, 2 is the upper chamber,
3 is a middle chamber, 4 is a lower chamber, 5 is a container (drawer container), 6 is a first slider, 7 is a second slider, 8 is a saturated melt, 9 is a substrate, 10a is a first aperture, 11 is the aperture of the second slider, 12 is the second
13 is a cover plate holding plate, 14 is a cover plate, and 15 is a second opening. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. An upper chamber for storing a saturated melt of the substance to be crystal grown, a middle chamber for accommodating a substrate on the surface of which the crystal is to be epitaxially grown, and an inflow chamber for the saturated melt used for the epitaxial growth. a boat body consisting of a lower chamber for accommodating a container to be stored; a first slider partitioning the upper chamber and the middle chamber and slidably provided; and the middle chamber and the lower chamber; and a second slider that slides in a predetermined relationship with the sliding of the first slider, the first slider has an epitaxy that is outside the boat body in a prepared state and that is attached to the first slider. During epitaxial growth, the epitaxial chamber is drawn into the boat body to communicate the upper chamber and the middle chamber, and after epitaxial growth is completed, it is placed at a predetermined position within the boat body. A first opening closed by a cover plate, which is covered by a required plate at a predetermined position within the boat body in a prepared state, and is pulled out from below the required plate during epitaxial growth to connect the upper chamber and the above. A second opening is provided that communicates with the middle chamber and is pulled out of the boat body after epitaxial growth is completed, and the second slider is subordinated to the first slider only after epitaxial growth. It is configured to slide on the boat, and is located outside the boat body during the preparation state and epitaxial growth, and is drawn into the boat body after the epitaxial growth is completed to form the middle chamber and the lower chamber. A liquid phase epitaxial crystal growth apparatus characterized in that an opening is provided to communicate with a chamber.