Sumitomo Electric Industries, Limited

Nippon Telegraph and Telephone Corporation

Nippon Telegraph and Telephone Public Corporation

Shintaro Miyazawa

Toshihiro Kotani

Akihisa Kawasaki

Kohji Tada

Masashi Mukaida

Takao Ishii

Junya Kobayashi

Yasuo Tazou

Ryusuke Nakai

Shigeo Murai

Kazuhisa Matsumoto

Yasushi Nanishi

Shinichi Akai

Hiroshi Morishita

Keigo Hoshikawa

An LiGaO.sub.2 single crystal manufactured by the Czochralski method has a crystallographic axis as a pulling direction set within an angle range of 30.degree. from a b- or a-axis direction. An LiGaO.sub.2 single-crystal substrate and a method of manufacturing the single crystal and the substrate are also disclosed.

LiGaO.sub.2 single crystal, single-crystal substrate, and method of

Method of manufacturing a LiGaO.sub.2 single-crystal substrate

A lattice matching device includes a substrate having thereon monocrystal regions having different lattice mismatches with respect to a LnBa.sub.2 Cu.sub.3 O.sub.x superconductor. A superconducting thin film is formed on the substrate, which film consists essentially of a superconductor of LnBa.sub.2 Cu.sub.3 O.sub.x wherein Ln represents yttrium or a lanthanide, and 6&lt;x&lt;7. The first and second superconducting thin film portions have different axes of orientation perpendicular to a main surface of the substrate, and arranged in contact with each other or at a distance which allows transmission of electron pairs from one to another.

Lattice matching device and method for fabricating the same

Lattice matching super conducting device with a- and c- axes

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 liquid encapsulation Czockralski method for growing a single crystal of a semiconductor compound which comprises: melting a semiconductor compound in the presence of a B.sub.2 O.sub.3 liquid encapsulant to form a two phase liquid; dipping a semiconductor seed crystal into the compound melt covered with the B.sub.2 O.sub.3 encapsulant; growing the crystal from the compound melt by pulling up and rotating the seed crystal; and, cooling the crystal in a cooling zone above a crucible. The cooling zone is maintained at a substantially uniform temperature distribution with a small temperature gradient by using primarily an independently controlled crystal cooling zone heater H3. In addition, an independently controlled melt heater H1 and an independently controlled crystal growing heater H2 are employed. Also, a crystal cooling zone heat shield 11 can be provided to aid in slowly cooling the grown crystal in the substantially uniform temperature distribution. Preferably, a crystal cooling zone heater H3 is employed to control the temperature distribution in the cooling zone. The semiconductor crystals produced by employing the process and apparatus of the invention are substantially crack-free both before and after grinding and cutting. Also the etch pitch density (EPD) of the semiconductor crystal material is significantly lower than conventionally produced material.

Liquid encapsulation method for growing single semiconductor crystals

The quality of a compound semiconductor crystal such as gallium arsenide used for an integrated circuit is upgraded by a method comprising optionally forming a protective film on the obverse surface and reverse surface of a substrate consisting of a compound semiconductor crystal, subjecting the substrate to a heat treatment in an inert atmosphere at a temperature of at least the same as the activating temperature after the ion implantation into the substrate and then optionally revmoving the protective film.

Method of homogenizing a compound semiconductor crystal prior to

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

Kanagawa, Japan

Shintaro Miyazawa