JPH0264090A - Container for liquid phase epitaxial growth - Google Patents

Abstract

PURPOSE:To reduce the moving rate of a raw material melted liquid on a carbon-made container so that the raw material melted liquid can be separated from a substrate in a single mass state by disposing a moderately inclined surface between an inclined surface capable of setting the substrate thereon and a horizontal surface for growing a crystal thereon. CONSTITUTION:A moderately inclined surface 6 gentler than an inclined surface 3 is disposed between the inclined surface 3 having a substrate 4 thereon in a carbon-made container 1 and a horizontal surface 2 at the bottom portion of the container. When a raw material melted liquid 5 transferred to the inclined surface 3 contacts with the substrate 4 to grow the thin filmy crystal thereof on the substrate 4 and subsequently returned to the horizontal surface 2, the presence of the moderately inclined surface 6 permits the reduction of the transferring rate of the raw material melted liquid 5 and the separation of the remaining raw material melted liquid 5 from the substrate 4 in a single mass state, thereby enabling to use the approximately whole surface of the substrate for devices although the portions of the surface of the substrate to be used for the devices have been heretofore limited.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention relates to a container for liquid phase epitaxial growth in which container growth is performed by a tilting method.

(Prior Art) The liquid phase epitaxial growth method using the tilting method is carried out using a crystal growth container 1 made of pure carbon and having an internal structure consisting of a horizontal surface 2 and an inclined surface 3 as shown in FIG. The base number 4 and the raw material 5 for crystal growth are charged into this. This is not shown in the figure or is vacuum sealed in a quartz sealed tube, placed in a rotary electric furnace (also not shown), and the temperature is raised to turn the raw material 5 for crystal growth into a raw material melt 5. This raw material melt 5 is rotated together with the electric furnace in the direction of the arrow in the figure, moved onto the inclined surface 3 as shown by the dotted line, and brought into contact with the substrate 4, whereby a thin film crystal is grown on the substrate due to temperature drop. Once the desired film thickness is obtained, the electric furnace is rotated in the opposite direction to the previous direction to separate the raw material melt 5 from the substrate 4 and terminate the growth.

(Problem to be solved by the invention) However, in the conventional technology, the speed at which the raw material melt moves after the growth is completed cannot be controlled. When the raw material melt is separated from the substrate (because the substrate, more precisely, the grown thin film crystal is large and the carbon is small), the raw material melt breaks off and some of it becomes sloppy. However, there was a problem in that it remained on the substrate as shown in FIG. If such stagnation remains, the area of the epitaxially grown thin film crystal will naturally be much smaller than the initial substrate area, making it impossible to obtain a thin film crystal with a sufficient area for the purpose, and reducing the area that can be used for devices. This is extremely uneconomical.

An object of the present invention is to provide a container for liquid phase epitaxial growth in which the moving speed of the raw material melt is suppressed so that the raw material melt behaves as one solid and will never break.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a gentle slope having a gentler slope than the slope between the slope on which the substrate is placed and the horizontal surface of the bottom of the container. .

(Function) When separating the raw material melt from the substrate after epitaxial growth,
The wettability between the raw material melt and carbon, which is the container material, is smaller than the wettability between the raw material melt and the substrate, so as a result, the area near the boundary between the substrate and carbon (indicated by the white arrow in Figure 2) This acts to try to tear the raw material melt apart. This is because the part on the carbon has low wettability and tries to flow smoothly, whereas the part on the substrate has high wettability and cannot keep up. The raw material melt has a large surface tension, so when it moves slowly it tends to move as a single mass, but when it moves quickly, the parts on the substrate break off and remain on the substrate as slivers for the above reason. become.

From the above, by reducing the speed at which the raw material melt moves on the carbon and increasing the relative speed at which it moves on the substrate, the part on the carbon is pushed by the part on the substrate. It is an object of the present invention to prevent this from tearing. This objective can be achieved by providing a gentle slope below the slope of the substrate in order to reduce the moving speed of the melt.

(Example) FIG. 1 shows an example of the present invention. A gentle slope 6 having a gentler slope than the slope 3 is provided between the slope 3 on which the substrate 4 is placed and the horizontal surface 2 at the bottom of the container.

A raw material 5 for crystal growth is charged into this container, vacuum-sealed in a quartz sealed tube, and placed in a rotary electric furnace, whereby the raw material 5 for crystal growth is turned into a raw material melt 5 by increasing the temperature. Next, the electric furnace is rotated in the direction of the arrow in the figure, moved onto the inclined surface 3 as shown by the dotted line, and brought into contact with the substrate 4 to grow a thin film crystal on the substrate due to temperature drop. When the required film thickness is obtained, the electric furnace is rotated in the opposite direction to the previous direction to separate the raw material melt 5 from the substrate 4 and finish the growth. As described above, even when this container which is an embodiment of the present invention is used, the growth procedure is the same as in the conventional example. In other words, the container according to the present invention has no effect on the conventional growth method, such as changing the procedure. has no effect at all.

FIG. 4 shows a container according to the present invention, which is 10 mm square and has a thickness of 1 mm.
Hg+-xCd, Te (x
Of the several examples in which a thin film crystal (approximately 20 μm thick) with a thickness of 0.22) was grown, an example in which the most thick film remained is shown. FIG. 3 shows a typical example where the same thin film crystal is grown on the same substrate under the same conditions using a conventional container. As is clear from the comparison, in the conventional example, the area that can be used for the device was limited by the remaining cisks, whereas in the embodiment according to the present invention, the usable area is significantly increased, and it is possible to use almost the entire surface. It has become possible.

(Effects of the Invention) As can be seen from the above, in the present invention, by reducing the speed at which the raw material melt moves on the carbon that is the container material, the raw material melt is separated from the substrate while remaining as a lump. This has an extremely excellent advantage in that the entire surface of the substrate can now be used for devices, whereas previously the surface area that could be used for devices was limited due to residual disks.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a container for epitaxial growth according to an embodiment of the present invention. FIG. 2 is a sectional view of a conventional epitaxial growth container. FIG. 3 is a diagram showing the appearance of the surface of a substrate after growing a thin film crystal using a conventional container. FIG. 4 is a diagram showing the appearance of the surface after growing a thin film crystal using the container according to the embodiment of the present invention. In the figure: 1. Carbon container; 2. Horizontal surface; 3. Slope, 4. Substrate, 5. Raw material melt (raw material for crystal growth) 6. gentle slope,
7. Growth substrate, 8. Nzuku.

Claims (1)

[Claims] In a container for liquid phase epitaxial growth, which has an inclined surface on which a substrate can be placed and a horizontal surface on which a raw material for crystal growth is placed, the slope between the inclined surface on which the substrate can be placed and the horizontal surface is gentler than the inclined surface. 1. A container for liquid phase epitaxial growth, characterized in that it is provided with a gentle slope.