JPS63277592A - Production unit for single crystal - Google Patents

Abstract

PURPOSE:To suppress the reduction of X-rays by the liquid sealant and enable correct and precise monitoring of crystal growth with X-ray detector, by allowing a ring to float on the melt in the crucible in the system for single crystal growth by the liquid-sealed Chokralsky method, provided with an X-ray detector as a monitor. CONSTITUTION:A ring having U-shaped cross section 14 is allowed to float on the melt 1 in crucible 3 and the weight of the ring 14 is controlled to position the inside bottom surface 15 lower than the solid-liquid interface. Thus, the X-rays 11 radiated from one side of the crucible 3 passes through the hollow part in the ring 14 instead of through the sealant 2 and the reduction of X-ray caused by the sealant can be avoided. As a result, the crystallization state near the solid-liquid interface can be monitored with clear contrast and the growth and control of single crystal becomes very easy compared with conventional apparatus.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is a liquid-sealed liquid-encapsulation method for manufacturing Li-V group compound semiconductors such as GaAs and InP and 1-Vl group compound semiconductors such as Zn5e and Cd'l'e. This invention relates to a device manufactured by the ski method.

[Conventional technology]

FIG. 5 shows an apparatus for producing single crystals using the conventional liquid-sealed Czochralski method.

In the figure, a raw material melt 1 and a liquid sealant 2 are stored in a crucible 5 supported by a lower shaft 6, and the contents in the crucible are heated and melted by a heater 9 disposed around the crucible 3. be done.

On the other hand, the upper shaft 5 with the seed crystal 4 attached to its lower end is lowered to bring the seed crystal 4 into sufficient contact with the raw material melt 1, and then the single crystal 7 is gradually pulled up. Note that 10 is a heat insulating material.

As means for monitoring this single crystal growth state, there are two methods: one is equipped with a window 13 for observing the crucible from above, and the other is equipped with a detector 12 that irradiates X-rays 11 from the side of the crucible and detects the transmitted image. . The latter method was effective because it allowed the state of the solid-liquid interface 8 of the crystal to be directly observed.

[Problem that the invention seeks to solve]

However, in conventional devices equipped with an X-ray detector, the X-rays are attenuated while passing through the liquid sealant 2, so the amount of X-rays reaching the detector 12 is weak and the transmitted image cannot be clearly seen. It was difficult to accurately monitor the state of the solid-liquid interface.

The present invention eliminates the above-mentioned drawbacks, and provides a manufacturing apparatus that makes it possible to manufacture a single crystal while minimizing the attenuation of X-rays by the liquid sealant, making the transmission image clear, and accurately monitoring the solid-liquid interface. This is what we are trying to provide.

[Means for solving problems]

The present invention includes a crucible containing a raw material melt and a liquid sealant;
Production of a single crystal that has a seed crystal attached to the lower end and an upper shaft that can be raised and lowered, a heater placed around the crucible, and an X-ray detection device installed on the side of the crucible to monitor the shape of the crystal O solid-liquid interface. In the device, it is an annular jig made of a relatively thin material, and when it is floated on the melt inside the crucible,
The single crystal is pulled up from the raw material melt surface in the center of the jig, using a jig adjusted such that the inner bottom of the jig is located below the raw material melt surface. This is a single crystal manufacturing device.

Note that the annular jig is made of BN, PBN, carbon, Al40.
s *Zr01. It can be made from ceramics such as ``O*nα, SiC, etc., and the cross-sectional shape does not matter as long as the annular jig floats in the raw material melt, but for example, it can be U-shaped or 0-shaped. In addition, in order to reduce the attenuation of X-rays, it is desirable that the jig be made of a plate as thin as the material allows.

[Effect]

FIG. 1 is a sectional view of a single-crystal O manufacturing apparatus which is one specific example of the present invention. The annular jig, which is a feature of the present invention, is applied to the conventional device shown in FIG. 5. In Figure 1,
The same members as in FIG. 3 have been given the same numbers, so their explanations will be omitted. The annular jig 14 has a U-shaped cross section as shown in FIG. 2, and by adjusting the weight, the inner bottom 15 of the annular jig is positioned below the solid-liquid interface 8.

By establishing the above relationship, most of the X-rays 11 irradiated from the side surface of the crucible 5 pass through the liquid sealant 2, but instead pass through the hollow part of the annular jig 14, and the liquid sealant Attenuation of X-rays due to Agent 2 could be avoided. As a result, the crystal state near the solid-liquid interface can be monitored with clear contrast, making it extremely easy to grow and control single crystals compared to conventional equipment.

[Metal practice]

A GaAs5 single crystal was manufactured using the apparatus shown in FIG.

A 90a As polycrystal obtained by the HB method was placed in a quartz crucible with a diameter of 4 inches, and 200f of B10m was placed therein.

The annular jig is made of PBN plate material with a wall thickness of 2cm, and the outer wall O radius is 9cm.
51, the radius of the inner wall was 40 m and the height was 50 m. When this annular jig was floated on the crucible, its bottom surface would be above the surface of the raw material melt, so a carbon weight k)2oat was placed on the annular jig.

A tungsten target of 80 KV and 2 mA was used for the X-rays.

When irradiating the above X-rays without using a ring jig) 0
．． It was almost impossible to observe the transmission image near the solid-liquid interface of the crystal.

On the other hand, when the above-mentioned annular jig is used, GaA at the solid-liquid interface
The shape of the s-crystal can be monitored with clear contrast, making it possible to manufacture single crystals with good reproducibility.

[Effects of the Invention] By employing the above-mentioned component tube, the present invention can avoid X@O attenuation and detect a transmitted image with good contrast, while accurately grasping the situation at the solid-liquid interface. This makes it possible to select the optimal crystal growth conditions and produce high-quality single crystals.

Brief description of the front surface FIG. 1 is a cross-sectional view of a single crystal manufacturing apparatus that is a specific example of the present invention, and FIG. 2 is an enlarged perspective view of an annular jig used in the apparatus shown in FIG. 1. , FIG. 3 is a sectional view of a conventional single crystal manufacturing apparatus.

Claims (3)

[Claims] (1) A crucible that accommodates the raw material melt and liquid sealant, an upper shaft with a seed crystal attached to its lower end that can be raised and lowered, a heater placed around the crucible, and a solid-liquid crystal placed on the side of the crucible. In a single crystal manufacturing apparatus equipped with an X-ray detection device for monitoring the shape of the interface, the jig is an annular jig made of a relatively thin material, and when the jig is floated on the melt in the crucible, Production of a single crystal, characterized in that the single crystal is pulled up from the raw material melt surface in the center of the jig using a jig whose inner bottom is adjusted to be located below the raw material melt surface. Device. (2) Annular jig made of BN, PBN, carbon, Al_2O
_3, ZrO_2, MgO, AlN, SiC, or other ceramics.
The apparatus for producing a single crystal as described in 1. (3) The single crystal manufacturing apparatus according to claim 1 or 2, wherein the annular jig has a U-shaped or O-shaped cross section.