JPH043101B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to an improvement in a liquid phase epitaxial crystal growth apparatus.

[Conventional technology]

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. 4 is a plan view showing the configuration of a conventional liquid phase epitaxial crystal growth apparatus used for such applications, and FIG. 5 is a cross-sectional view taken along the - line.
In the figure, 1 is 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 first slider that partitions the middle chamber 3 and the lower chamber 4. A slider 2, 8 a saturated gallium (Ga) melt housed in the upper chamber 2, 9 placed on the second slider 7 and a middle chamber 3
10 is an opening provided in the first slider 6, 11 is an opening provided in the second slider 7, and 12 is an opening provided in the second slider 7. This is an L-shaped plate that is provided on one slider 6 and that moves the second slider 7 with a time delay when the first slider 6 is moved in the direction of the arrow shown.

It should be noted that all of the above-mentioned parts are made of carbon plates except for the substrate 9 and the saturated Ga melt 8.

In the conventional apparatus configured in this way, the substrate 9 is placed in the middle chamber 3 in the state shown in FIGS. 4 and 5, and the saturated Ga melt 8 is accommodated in the upper chamber 2.
This boat is placed in a growth furnace and the temperature is raised. After the boat has reached equilibrium at a predetermined temperature, the first slider 6
When moved in the direction of the arrow, the aperture 10 communicates between the upper chamber 2 and the middle chamber 3, through which the saturated Ga melt 8 falls and flows into the middle chamber 3. Substrate 9 is immersed. By slowly cooling the growth furnace in this state, epitaxial crystal growth is obtained on the substrate 9. During this epitaxial crystal growth, the saturated Ga melt 8 is connected to the upper chamber 2 and the middle chamber 3 through the opening 10. After the epitaxial crystal growth is completed, the first slider 6 is further moved 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 is made to flow into the drawing container 5.

[Problem that the invention seeks to solve]

The conventional liquid phase epitaxial crystal growth apparatus has a complicated structure because the first and second sliders 6 and 7 are connected to each other, and the boat is large because each slider 6 and 7 is long. There are problems in that the growth furnace requires a long soaking length, and saturated Ga
Since the melt 8 falls directly and soaks the substrate 9, there is a problem that the oxide on the surface of the saturated Ga melt 8 also soaks the substrate 9.

The present invention has been made to solve the above-mentioned problems, and aims to provide a liquid phase epitaxial crystal growth apparatus having a short boat length, miniaturization, and high throughput.

[Means for solving problems]

The liquid phase epitaxial crystal growth apparatus according to the present invention comprises an upper chamber for accommodating a saturated melt, a middle chamber for accommodating a substrate, and a lower chamber for accommodating a saturated melt after epitaxial crystal growth. Although it has a three-stage structure, there is only one slider, and a convex portion is formed on this slider, which becomes the side wall of the middle-stage chamber, isolates the upper-stage chamber and the middle-stage chamber in the preparation state, and connects them during epitaxial crystal growth. This is what I did.

[Effect]

In this invention, by providing the slider with a convex portion that becomes the side wall of the middle chamber, it is possible to connect and disconnect each chamber by moving the slider, so that the saturated melt between each chamber can be Can move.

〔Example〕

FIG. 1 is a cross-sectional view of a liquid-phase epitaxial crystal growth apparatus in a prepared state showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view during the epitaxial crystal growth process.
FIG. 3 is a cross-sectional view of a state in which epitaxial crystal growth is completed.

In these figures, 1 to 5 and 8 and 9 are the same as in FIGS. 4 and 5, and 13 is a slider, and this slider 13 is provided with a convex portion 14 that becomes the side wall of the middle chamber 3. . 15 is a substrate holder that holds the substrate 9, and an inlet for the saturated Ga solution 8 is formed at the bottom of the basic holder so that the saturated Ga melt 8 introduced from the upper chamber 2 flows from the lower part of the middle chamber 3. has been done. 16 is an opening provided in the slider 13.

In the liquid phase epitaxial crystal growth apparatus having the slider 13 having the convex portion 14 configured as described above, the upper chamber 2 is in the state shown in FIG.
A saturated Ga melt 8 is placed in the middle chamber 3, and a substrate 9 is placed in the middle chamber 3, and the boat body 1 is placed in a growth furnace and heated. After the boat body 1 reaches equilibrium at a predetermined temperature, when the slider 13 is moved in the direction of the arrow, the convex portion 14 of the slider 13 as shown in FIG.
The upper chamber 2 and the middle chamber 3, which had been partitioned by , are now in communication with each other, through which the saturated Ga melt 8 flows into the middle chamber 3 and immerses the surface of the substrate 9. By slowly cooling the growth furnace in this state, epitaxial crystal growth occurs on the substrate 9. After the required epitaxial crystal growth is completed, the slider 13 is further moved in the direction of the arrow, and this opening 16 allows
The middle chamber 3 and the lower chamber 4 are communicated with each other, and the saturated Ga melt 8 is caused to flow into the drawing container 5.

In this way, not only can an epitaxial crystal growth layer having a mirror surface be obtained on the substrate 9, but also the structure of the boat body 1 can be simplified.

In the above embodiment, epitaxial crystal growth using the saturated Ga melt 8 was exemplified, but it goes without saying that it can be used for other crystal growth as well.

〔Effect of the invention〕

As explained above, this invention is a boat consisting of an upper chamber for storing a saturated melt, a middle chamber for accommodating a substrate on which epitaxial crystal growth is to be performed, and a lower chamber for accommodating a saturated melt after epitaxial crystal growth. The main body is provided, a slider is provided movably between the middle chamber and the lower chamber, and a convex portion that becomes a side wall of the middle chamber is formed on the slider.
By moving this slider, each chamber can be communicated with or shut off, making it possible to simplify the structure and downsize the device.If the device is of the same size, the processing capacity can be increased by using this invention. can do. Furthermore, when pouring the saturated melt into the middle chamber, by pouring it from the bottom of the middle chamber, the oxides on the surface of the saturated melt do not adhere to the substrate, making it possible to obtain a high-quality epitaxial crystal growth layer. There are advantages.

[Brief explanation of drawings]

1, 2, and 3 are cross-sectional views showing the configuration of a liquid phase epitaxial growth apparatus according to an embodiment of the present invention, with FIG. 1 showing the preparation state and FIG. 2 showing the epitaxial crystal growth state. , Fig. 3 is a diagram showing the completed state of epitaxial crystal growth, Fig. 4,
FIG. 5 is a top view and a side sectional view of a conventional liquid phase epitaxial growth apparatus. In the figure, 1 is the boat body, 2 is the upper chamber,
3 is the middle chamber, 4 is the lower chamber, 8 is the saturated Ga melt,
9 is a substrate, 13 is a slider, 14 is a convex portion, and 15 is a substrate holder. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. An upper chamber that stores a saturated melt of a substance used for crystal growth, a middle chamber that accommodates a substrate on which a crystal is to be epitaxially grown using the saturated melt on its surface, and a saturated melt after epitaxial growth is completed. In a liquid phase epitaxial crystal growth apparatus equipped with a boat body consisting of a lower chamber containing Then,
A liquid phase epitaxial growth apparatus characterized in that a convex portion is provided that isolates the upper chamber and the middle chamber in a prepared state and allows them to communicate during epitaxial crystal growth.