JPS6128635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for performing liquid phase epitaxial growth in manufacturing edge-colored light emitting diodes and the like.

In the production of GaP (gallium phosphide) green light-emitting diodes, it is well known that relying on liquid phase epitaxial growth methods, especially two-melt continuous growth methods, is effective in obtaining high luminous efficiency. . By the way, the conventional apparatus for carrying out this two-melt continuous growth method is as shown in FIG. It is divided into three stages, an upper stage, a middle stage, and a lower stage by plates 21 and 22, and melt storage chambers 24 and 25 are formed in the upper stage divided by a partition wall 23, and these are filled with Ga (gallium), GaP polycrystal, and dopant, respectively. N-type melt a and P-type melt b made of a mixture of N-type and P-type epitaxial growth are stored, and a substrate storage chamber 26 is formed in the middle, and a carrier 27 is used inside this chamber. supported
A large number of GaP substrates 28 are accommodated therein. When performing epitaxial growth, the hollow cylindrical body 20 is placed in a heating furnace (not shown) with the saucer 29 disposed below it, and while being heated and maintained at a predetermined temperature in an appropriate atmospheric gas, Upper slide plate 21
is moved in the direction of the arrow using the operating rod 30 connected to this, and the continuous hole 3 bored in the upper slide plate 21 is moved.
1 is positioned below the melt storage chamber 24 of the N-type melt a, and the N-type melt a is allowed to flow down into the substrate storage chamber 26 and come into contact with the GaP substrate 28, and then heated to a constant temperature to form the GaP substrate. An N-type epitaxial layer is grown on the surface of 28, and when this is completed, the lower slide plate 22 is moved in the direction of the arrow using the operation rod 32, and the communication hole 33 bored therein is inserted into the substrate storage chamber 26.
The N-type melt remaining in the substrate storage chamber 26 located below is discharged into the receiving tray 29. Next, after returning the lower slide plate 22 to the position before movement, the upper slide plate 21 is further moved in the direction of the arrow to open the communication hole 3.
1 is positioned below the melt storage chamber 25 of the P-type melt b, and the P-type melt b is allowed to flow down into the substrate storage chamber 26, and the temperature is lowered to a constant temperature in the same manner as in the case described above.
P on top of the previously grown N-type epitaxial layer.
2. Grow a shaped epitaxial layer. When the growth of the P-type epitaxial layer is completed, the entire growth apparatus is taken out of the heating furnace, and the N-type melt a in the saucer 29 and the P-type melt b remaining in the substrate storage chamber 26 are recycled. One cycle is completed by transferring the melt to each melt storage chamber of the growth apparatus to be used next. However, in such an apparatus, as mentioned above, each time one epitaxial growth is performed, it is necessary to transfer the N-type and P-type melts from the growth apparatus or saucer to the next growth apparatus. First, the operation is time-consuming, and in the process of transferring, for example, in the case of N-type melt, it is transferred through the saucer 29, so that the melt itself becomes contaminated as it is repeated. Furthermore, in the process of cooling down in the heating furnace, GaP polycrystals are precipitated on the surface of the tray in the case of the N-type melt a stored in the tray, and also in the case of the P-type melt b.
0, and because GaP polycrystals precipitate on the surfaces of the slide plates 21 and 22, the components of the mixture each time it is used,
In particular, there was a disadvantage that the amount of components in the GaP polycrystal varied greatly, and the amount of change varied depending on the growth process. Therefore, it is extremely difficult to reuse the melt in the conventional apparatus described above.

The present invention has been made to eliminate such drawbacks, and its purpose is to selectively communicate with each other through relative movement between the melt container and the substrate container, thereby improving the structure of the structure. It is an object of the present invention to provide a liquid phase epitaxial growth apparatus which is greatly simplified, completely eliminates the chance of contamination due to contact with a saucer, etc. as in the prior art, and allows the melt to be reused very easily.

The liquid phase epitaxial growth apparatus according to the present invention includes:
In an apparatus for growing a plurality of different epitaxial layers, a melt container has a plurality of concave melt storage chambers each having an opening on one surface, and a concave storage chamber having an opening on one surface and capable of accommodating a plurality of substrates. and a substrate container having a storage chamber are arranged so as to be movable with respect to each other so that the opening side of each storage chamber faces each other so that the storage chamber of the substrate can selectively communicate with each melt storage chamber, and The present invention is characterized in that a shielding portion having an area sufficiently larger than the opening area of each opening of the melt storage chamber is provided around the storage chamber of the substrate container.

EMBODIMENT OF THE INVENTION The present invention will be specifically explained below based on drawings showing embodiments thereof.

FIG. 1 is a front sectional view of a liquid phase epitaxial growth apparatus according to the present invention, and FIG. 2 is a side sectional view taken along the line - in FIG. 1, in which 1 is a melt container and 2 is a substrate container. Both have a rectangular parallelepiped appearance as a whole, and the upper front and rear edges of the melt container are provided with flange portions 1a and 1a along the entire length.
1a is extended outward, and a groove 2a is provided on the lower surface of the substrate container 2, into which the upper part of the melt container 1 fits, extending between both left and right ends of the substrate container 2. The upper side wall is aligned with the upper bottom wall surface of the groove 2a, and the flange portions 1a, 1
guide grooves 2b, 2b that slidably hold the flange portions 1a, 1b are formed.
By fitting into the grooves 2b and 2b, the melt container 1 and the substrate container 2 are slidably disposed relative to each other with the upper surface of the melt container 1 and the upper bottom surface of the groove 2a in contact with each other. The melt container 1 is configured to be able to move the melt container 1 relative to the substrate container 2 by means of an operating rod 3 connected to a locking hole in a protrusion 2c extending from one end of the container 2. A storage chamber 1c for the N-type melt a and a storage chamber 1d for the P-type melt b are formed approximately in the center in parallel in the longitudinal direction of the melt container 1, each having a concave shape. The openings 1c and 1d are opened on the upper surface of the melt container 1 facing the substrate container 2. On the other hand, the substrate container 2 also has a substrate storage chamber 2d in the center.
is formed in a concave shape, and the opening of the substrate storage chamber 2d is opened downward in the upper bottom wall of the groove 2a so as to face the melt container 1. Further, on both sides of the opening of the substrate storage chamber 2d, there are shielding portions 2 formed of the upper bottom surface of the groove 2a and having an area sufficiently larger than the opening area of each opening of the melt storage chambers 1c and 1d.
E and 2f are provided. A large number of substrates 4 are housed in the substrate storage chamber 2d while being supported by carriers 5, and the carrier 5 is fixed to the wall of the substrate storage chamber 2d using a fastener (not shown). .

When the substrate container 2 is moved and the opening of the substrate storage chamber 2d is opposed to the N-type melt storage chamber 1c as shown in FIGS. 1 and 4, the melt storage chamber 1d is opened.
is opposed to the shielding part 2f, and when the opening of the substrate storage chamber 2d is opposed to the melt storage chamber 1d, the melt storage chamber 1c is opposed to the shielding part 2e, and the opening of the substrate storage chamber 2d is opposed to the melt storage chamber 1d. When facing one of the melt storage chambers, the other melt storage chamber is always closed facing the shielding part, and the entire device is closed at 180 degrees.
゜Even when the device is tipped over, the melt in the closed melt storage chamber will not be scattered outside.

Next, by the device of the present invention configured as described above,
An example of an operating procedure for manufacturing a GaP green light emitting diode by epitaxial growth will be described. First, as shown in FIG. 1, N-type melt and P-type melt made of Ga, GaP polycrystal, and dopant are placed in the N-type melt storage chamber 1c and the P-type melt storage chamber 1d of the melt container 1, respectively. A plurality of GaP substrates 4 are accommodated in the substrate accommodation chamber 2d of the substrate container 2 using fasteners and carriers 5 (not shown), and the whole is assembled as shown in FIG. The sample is then placed in a heating furnace (not shown) and heated to a predetermined temperature in an appropriate atmospheric gas. While maintaining the temperature at a predetermined temperature, the entire growth apparatus is turned over in a heating furnace as shown in FIG. 3, and the positions of the melt container 1 and the substrate container 2 are turned upside down. As a result, the opening of the P-type melt storage chamber 1d is closed by the shielding part 2f, so the P-type melt b does not flow out, but the N-type melt a flows into the substrate storage chamber 1d.
d and comes into contact with the substrate. When the temperature is lowered to a certain temperature in this state, an N-type epitaxial layer is grown on the substrate surface. When this N-type epitaxial growth is completed, the growth apparatus is returned to the state shown in FIG. 1 before being overturned, and the N-type melt a is returned to the N-type melt storage chamber 1c.

Next, the substrate container 2 is moved in the direction of the arrow by the operation rod 3, and the opening of the substrate storage chamber 2d is aligned with the opening of the P-type melt storage chamber 1d of the melt container 1, as shown in FIG. let As a result, the opening of the N-type melt storage chamber 1c is closed by the closing portion 2e. If the device is turned over again, the fifth
As shown in the figure, the P-type melt b in the P-type melt storage chamber 1d flows down into the substrate storage chamber 2d, and the substrate 4
Contact with an N-type epitaxial layer grown on the surface. When the temperature is lowered to a certain temperature again, a P-type epitaxial layer grows on top of the N-type epitaxial layer. When the P-type epitaxial growth is completed, the state is returned to the state shown in FIG. 4 before the overturning, and the P-type melt b in the substrate storage chamber 2d is returned to the P-type melt storage chamber 1d. N
When the formation of the P-type and P-type epitaxial layers is completed, the entire device or only the substrate container 2 is taken out.
Replace the board 4 with another one and create the melt storage chamber 1.
The N-type and P-type melts in c and 1d can be left as they are and an epitaxial layer can be grown again by the above-described procedure. During this time, both the N-type melt and the P-type melt only move back and forth between the melt storage chambers 1c and 1d and the substrate storage chamber 2d, and do not come into contact with anything else, resulting in extremely little contamination.

Note that the GaP polycrystals and some dopants consumed by the N-type and P-type epitaxial growth are replenished as appropriate each time. The amount of this replenishment is determined by the epitaxial growth conditions such as temperature and gas flow rate, and is approximately constant. Therefore, the consumption amount can be predicted in advance and the mixture can be prepared. The amount of GaP polycrystals does not vary greatly each time due to adhesion to the substrate, and it can be reused simply by replenishing the mixture corresponding to the amount lost during epitaxial growth.

As described above, the present invention includes a melt container,
By moving relative to the substrate container, the melt can be transferred easily and with a simple configuration, so there is no chance of discoloration during the process, and in addition, there is less waste of melt, and it can be used repeatedly. The present invention exhibits excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an embodiment of the liquid phase epitaxial growth apparatus according to the present invention, and FIG.
A side cross-sectional view taken along the - line in the figure, Figures 3, 4, and 5 are explanatory diagrams of operations during epitaxial growth, and Figure 6 is a cross-sectional view of the growth apparatus used in the conventional two-melt continuous growth method. be. 1...Melt container, 1c, 1d...Melt storage chamber, 2...Substrate container, 2d...Substrate storage chamber.

Claims (1)

[Claims] 1. In an apparatus for growing a plurality of different epitaxial layers, a melt container having a plurality of concave melt storage chambers each having an opening on one side and a concave housing capable of accommodating a plurality of substrates each having an opening on one side. and a substrate container having chambers, with the opening side of each storage chamber facing each other, and disposed so as to be movable with respect to each other so that the storage chamber of the substrate can selectively communicate with each melt storage chamber, A liquid phase epitaxial growth apparatus characterized in that a shielding portion having an area sufficiently larger than the opening area of each opening of the melt storage chamber is provided around the storage chamber of the substrate container.