CS200784B1 - Device for single-crystal production - Google Patents

Description

( ⁵⁴ ) MONOCRYSTAL PRODUCTION EQUIPMENT

The invention relates to a device for the production of single crystals.

Bulk single crystals of binary and ternary compounds can be prepared by a variety of methods in a vertical or horizontal configuration, either from the melt itself or from the melt solution. Among the most widely used methods for growing volumetric single crystals from a stoichiometric melt in a horizontal arrangement are the Bridgman method or the zone melting method or the Eoomgard method. Methods for growing single crystals from solution in a melt in a horizontal arrangement are method. Mason and Cook or Method 8 by internal regulation of composition.

Band refining can be used to obtain pure single crystals. Vibration melt mixing is used to accelerate the refining process, thereby reducing the effect of the resulting diffusion layer and improving the conditions for transporting impurities from the crystallization interface to the melt as well as transporting the surface slag layer to the end of the ingot, which is often a source of defects such as heterogeneous nucleation. twinning in single crystal growth.

The vibration mixing can advantageously be used both for the zone refining of the melt itself and for refining from the solution in the melt. Existing methods of applying vibration mixing have been limited to melt refining alone. Mixing by rotation of the crucible or seed is used for the cultivation of single crystals.

200 784

200 784

The disadvantages of rotary mixing methods in single crystal cultivation and are manifested mainly by the fact that the effect of mixing is dependent on the diameter of the grown crystal - different peripheral velocity, and leads to micro-homogeneities.

These drawbacks are overcome by the device according to the invention for producing single crystals by growing them from the melt itself or from the solution in the melt. The principle of the device consists in that the single crystal cultivation vessel is mounted on at least two supports, the distance of these supports from the single crystal crypting container during the crystallization process remains the same

The advantages of the device consist mainly in increasing the rate of the crystallization process, i.e. the movement of the molten zone and in increasing the homogeneity of the molten zone, and thus creating better conditions for increasing the homogeneity of the cultivated single crystal. This is even more pronounced in the case of crystallization from solution in the melt. The process according to the invention makes it possible to apply vibration mixing, for example, in zone refining from a solution in the melt. At the same time, it provides a vibration mixing of washed away impurities from the crystallization treatment.

The device is explained in more detail below with reference to the accompanying drawing, in which a schematic diagram is drawn.

The sealing container 6, in this case a quartz ampoule, provided with holders 2 ', is supported on two rollers 11 which are fastened to the supporting supports 2' connected to the base of the entire device, which is a fixed, moving furnace. Alternatively, however, the furnace may be constructed such that the furnaces are rigidly connected to the base of the device and the base with the vibrator, the supports 2 and the container 6 is moved, while maintaining constant distances between the supports 2> of the holder 10 and the vibrator. for both alternatives so that the vial 6 connected by the β holders 7 ^{8 8 by the} vibrator 1 can be diverted from the horizontal by -10 °. The left-hand container holder 6 is tapered at the end and bonded to a portion of the exponential pin 2 of the vibrator 1. The vibrator 1 is mounted on a holder 10 connected to the base of the device. Thus, during the crystallization process to ensure a constant distance pěetovací container 6 with respect to the supports ⁸ of the vibrator 2 first vibrator 1 is connected to the power amplifier výetup

8. Amplifier 8 is driven by function generator 2 ·

The device according to the invention operates as follows:

The longitudinal vibrations induced by the vibrator 1 are transferred via the holder ^{28 of the} actual trapping container 6 to the molten zone 5 in the ingot 4. Constant distances of the supports 2 of the trapping container 6 and the vibrator 1 ensure that the distribution of strains and knots does not change throughout the process. On the function generator 9 ee, it adjusts the frequency, amplitude and DC component so that the reciprocating and reflected waves interact with each other on the surface of the molten zone 5 to move away from the crystallization interface, i.e. in the direction of the band motion.

This ensures mixing of the molten zone 2 of the solution in the melt, rinsing the crystallization interface and washing away the teat-like layer of impurities that accumulate at the end of the ingot 4 after the molten zone 5 has passed.

Claims (1)

< tklt TllilSZU Apparatus for producing single crystals by growing them with a micrometer size in a melt, characterized in that the baking container (6) and the crystal (4) are rigidly connected and are capable of being deposited at least on two supports (3) »the distance between these supports (3) and the vibrator (1) from the cultivation vessel (6) of the single crystals remains the same during the cryogenisation of the proees ·