Sumitomo Electric Industries, Limited

Nippon Telegraph and Telephone Public Corporation

Panasonic Intellectual Property Management Co., Ltd.

Akihisa Kawasaki

Toshihiro Kotani

Shintaro Miyazawa

Kohji Tada

Ryusuke Nakai

Yasushi Nanishi

Keigo Hoshikawa

Herein disclosed are apparatuses for manufacturing compound semiconductor polycrystals comprising a pressure vessel, an upper shaft, a container for a first component fixed to the upper shaft, a heater around the container, a lower shaft, a susceptor and a crucible for charging a second component, a heater for the crucible and a communicating pipe for spatially connecting the container and the crucible optionally provided with a porous member at the lower extremity and/or a cylindrical member for confining a space over a part of the melt surface contained in the crucible from the remaining inner space of the vessel, the apparatuses permitting the substantial reduction of the reaction time and an improvement of the yield of the polycrystals due to the presence of the porous member and/or the cylindrical member separating the inner space of the vessel into two portions.

Method for synthesizing compound semiconductor polycrystals and

A method and apparatus for drawing up a single crystal using a double-crucible apparatus and a liquid capsule process. The inner crucible of the double-crucible apparatus is attached to the outer crucible. The presence of through holes in the lower portions of the inner crucible allow communication between the molten raw material in the inner and outer crucibles. Through holes in the upper portion of the inner crucible allow communication between the liquid sealing agent covering the molten raw material in the inner and outer crucibles. Single crystals having uniform impurity concentration and few defects are rapidly grown because the interface between the liquid sealing agent and molten raw material in the inner crucible is even with the same interface in the outer crucible.

Method of drawing-up a single crystal using a double-crucible apparatus

A method and apparatus for recovering the inner crucible used in a double crucible process of drawing-up a single crystal. The inner crucible is recovered by pulling up the inner crucible above the molten raw material using only a simply arranged jig which does not require reconstruction of the vessel accommodating the single crystal drawing-up system. The arrangement is such that the inner crucible is allowed to rotate during the period in which the single crystal is being grown.

Crucible recovering method and apparatus therefor

An apparatus for pulling a single crystal by CZ method or LEC method is improved. To this end, the heater for heating the inside of the furnace is divided at least in the vicinity of the solid-liquid interface into at least two heaters. Using this apparatus, a single crystal with a decreased dislocation density can be obtained.

Process for pulling a single crystal

A single crystal is prepared by drawing up a single crystal by the Czochralski process and cooling it at a temperature not lower than 600.degree. C. in vacuo. In this manner a single crystal having a dislocation density of 1.5.times.10.sup.4 cm.sup.2 or less is prepared.

Single crystal article

A process for preparing a single crystal comprising drawing up a single crystal by the Czochralski process and cooling it at a temperature not lower than 600.degree. C. at a reduced pressure or in vacuo, by which a single crystal having a dislocation density of 1.5.times.10.sup.4 cm.sup.2 or less is prepared.

Process for preparing single crystal

A process for manufacturing boron-doped GaAs single crystals which comprises preparing a mixture of boron, gallium and arsenic covered by a liquid B.sub.2 O.sub.3 encapsulant, melting the mixture, pulling up boron-doped GaAs crystals from the mixture melts in accordance with the LEC method, crushing those crystals into small pieces after removing the seed end therefrom, remelting those pieces in the presence of B.sub.2 O.sub.3, and pulling up single crystals from the mixture melts in accordance with the LEC method.

Growing community of inventors

Osaka, Japan

Akihisa Kawasaki