Special-shaped PBN-quartz combined crucible

Abstract

The invention relates to the technical field of semiconductor material production, and discloses a special-shaped PBN-quartz combined crucible. The special-shaped PBN-quartz combined crucible comprises a quartz crucible, a PBN crucible and a quartz cap, wherein the quartz crucible comprises a coating cavity and a quartz crucible seed crystal cavity; the PBN crucible comprises a raw material cavityand a PBN crucible seed crystal cavity; the PBN crucible and the quartz cap are both arranged in the inner cavity of the quartz crucible; the quartz cap is arranged at one end close to the opening ofthe quartz crucible, and the opening of the quartz cap faces the PBN crucible; the seed crystal cavity of the quartz crucible comprises a first seed crystal cavity section and a second seed crystal cavity section, the second seed crystal cavity section is tightly attached to the outer wall of the seed crystal cavity of the PBN crucible; and spacing areas are arranged between the first seed crystal cavity section and the coating cavity of the quartz crucible and the PBN crucible. According to the invention, a semiconductor material is allowed to obtain a flat growth interface, the phenomenon of thermal stress concentration of crystals is effectively improved, and crystals with large size, high dislocation density and good uniformity are obtained.

Description

technical field [0001] The invention relates to the technical field of semiconductor material production, in particular to a special-shaped PBN and quartz combined crucible. Background technique [0002] Vertical temperature gradient solidification (VGF) and vertical Bridgman method (VB) are currently the most important production methods for compound semiconductor gallium arsenide (GaAs) and indium phosphide (InP) materials in the market. After long-term development, PBN crucibles and quartz crucibles are used in the current production process, and the thermal conductivity of the PBN crucible along the direction of the crucible wall is 62.8W / (m K) -1 , the high thermal conductivity causes the gap between the PBN crucible and the quartz crucible to have a great influence on the heat conduction of the temperature field. [0003] When the shapes of the PBN crucible and the quartz crucible are similar and they are tightly fitted, a large amount of heat flow is conducted away t...

AI Technical Summary

Problems solved by technology

The concave growth interface of semiconductor materials tends to produce fine twins at the edge, which is not conducive to the growth of large-sized crystals; in addition, the substrate impurity concentration obtained by crystals on the same horizontal plane is distributed in concentric circles, and the uniformity is poor, and the PBN crucible and the quartz crucible seed crystal The position of the inflection point from the cavity to the tapered part produces a large thermal stress, the ingot and the processed substrate are easy to crack and fragment, and the concentration of thermal stress is easy to produce polycrystalline, and the dislocation density is high; when the two are completely separated, The latent heat of phase change becomes the main factor affecting the shape of the growth interface, and the growth interface also presents a concave melt shape, but the PBN crucible is completely separated from the quartz crucible, and the overall thermal stress is relatively average; , when the cone angle and the equidiameter position are separated, the growth interface tends to be flat, which is conducive to obtaining large-sized crystals with low dislocation density and high uniformity, but the stress concentration problem at the seed cavity and the cone angle position is still difficult to solve

[0004] At present, in the industrial mass production of GaAs and InP materials on the market, the problem of the gap between the PBN crucible and the quartz crucible has not been paid attention to. The shapes of the two are basically similar, and the gap between the two cannot be well controlled.

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