Sumitomo Electric Industries, Limited

Takashi Sakurada

Makoto Kiyama

Hideaki Nakahata

Tomohiro Kawase

Kouhei Miura

Yoshiyuki Yamamoto

Koji Uematsu

Michimasa Miyanaga

Tatsuya Tanabe

Takao Nakamura

Katsushi Akita

Youichi Nagai

Shinsuke Fujiwara

Koji Katayama

Naho Mizuhara

Issei Satoh

Keisuke Tanizaki

Shin Hashimoto

Susumu Yoshimoto

Ayako Ikeda

Takuji Okahisa

Kyoko Okita

Tomoki Uemura

Tomihito Miyazaki

Yoshiaki Hagi

Shunsaku Ueta

Eiryo Takasuka

Sho Sasaki

Hidehiko Mishima

Satoshi Arakawa

Naoki Kaji

Hirokazu Eguchi

Seiji Nakahata

Yusuke Yoshizumi

An electrically conductive GaAs crystal has an atomic concentration of Si more than 1×10cm, wherein density of precipitates having sizes of at least 30 nm contained in the crystal is at most 400 cm. In this case, it is preferable that the conductive GaAs crystal has a dislocation density of at most 2×10cmor at least 1×10cm.

Crystal and substrate of conductive GaAs, and method for forming the same

In a case where a detector is positioned in a [11-20] direction, and where a first measurement region including a center of a main surface is irradiated with an X ray in a direction within &#xb1;15&#xb0; relative to a [&#x2212;1-120] direction, a ratio of a maximum intensity of a first intensity profile is more than or equal to 1500. In a case where the detector is positioned in a direction parallel to a [&#x2212;1100] direction, and where the first measurement region is irradiated with an X ray in a direction within &#xb1;6&#xb0; relative to a [1-100] direction, a ratio of a maximum intensity of a second intensity profile is more than or equal to 1500. An absolute value of a difference between maximum value and minimum value of energy at which the first intensity profile indicates a maximum value is less than or equal to 0.06 keV.

Silicon carbide single crystal substrate

An electrically conductive GaAs crystal has an atomic concentration of Si more than 1&#xd7;10cm, wherein density of precipitates having sizes of at least 30 nm contained in the crystal is at most 400 cm. In this case, it is preferable that the conductive GaAs crystal has a dislocation density of at most 2&#xd7;10cmor at least 1&#xd7;10cm.

Relates to a method of producing a semiconductor crystal having generation of a defect suppressed in the semiconductor single crystal. The production method includes the steps of: forming a boron oxide film () on the inner wall of a growth container () having a bottom section and a body section continuous to the bottom section; bringing the boron oxide film () into contact with boron oxide melt containing silicon oxide to form a boron oxide film () containing silicon oxide on the inner wall of the growth container (); forming raw material melt () above seed crystal () placed in and on the bottom section of the growth container (); and solidifying the raw material melt () from the seed crystal () side to grow a semiconductor single crystal.

Growth container

Relates to a method of producing a semiconductor crystal having generation of a defect suppressed in the semiconductor single crystal. The production method includes the steps of: forming a boron oxide film on the inner wall of a growth container having a bottom section and a body section continuous to the bottom section; bringing the boron oxide film into contact with boron oxide melt containing silicon oxide to form a boron oxide film containing silicon oxide on the inner wall of the growth container; forming raw material melt above seed crystal placed in and on the bottom section of the growth container; and solidifying the raw material melt from the seed crystal side to grow a semiconductor single crystal.

Method of producing semiconductor single crystal

A method of producing a semiconductor crystal is provided. The method includes the steps of preparing a longitudinal container with a seed crystal and an impurity-containing melt placed in a bottom section and with a suspension part arranged in an upper section and suspending a dropping raw material block made of a semiconductor material having an impurity concentration lower than the impurity concentration of the impurity-containing melt, and creating a temperature gradient in the longitudinal direction of the longitudinal container to melt the dropping raw material block, and solidifying the impurity-containing melt from the side that is in contact with the seed crystal () while dropping a produced melt into the impurity-containing melt, thereby producing a semiconductor crystal.

Method and apparatus for producing semiconductor crystal, and semiconductor crystal

A method of manufacturing a nitride substrate includes the following steps. Firstly, a nitride crystal is grown. Then, the nitride substrate including a front surface is cut from the nitride crystal. In the step of cutting, the nitride substrate is cut such that an off angle formed between an axis orthogonal to the front surface and an m-axis or an a-axis is greater than zero. When the nitride crystal is grown in a c-axis direction, in the step of cutting, the nitride substrate is cut from the nitride crystal along a flat plane which passes through a front surface and a rear surface of the nitride crystal and does not pass through a line segment connecting a center of a radius of curvature of the front surface with a center of a radius of curvature of the rear surface of the nitride crystal.

Method of manufacturing nitride substrate, and nitride substrate

A compound semiconductor single-crystal manufacturing device () is furnished with: a laser light source () making it possible to sublime a source material by directing a laser beam onto the material; a reaction vessel () having a laser entry window () through which the laser beam output from the laser light source () can be transmitted to introduce the beam into the vessel interior, and that is capable of retaining a starting substrate () where sublimed source material is recrystallized; and a heater () making it possible to heat the starting substrate (). The laser beam is shone on, to heat and thereby sublime, the source material within the reaction vessel (), and compound semiconductor single crystal is grown by recrystallizing the sublimed source material onto the starting substrate (); afterwards the laser beam is employed to separate the compound semiconductor single crystal from the starting substrate ().

Compound semiconductor single-crystal manufacturing device and manufacturing method

Method of high-yield manufacturing superior semiconductor devices includes: a step of preparing a GaN substrate having a ratio S/S&#x2014;of collective area (Scm) of inversion domains in, to total area (S cm) of the principal face of, the GaN substrate&#x2014;of no more than 0.5, with the density along the (0001) Ga face, being the substrate principal face, of inversion domains whose surface area where the polarity in the [0001] direction is inverted with respect to the principal domain (matrix) is 1 &#x3bc;mor more being D cm; and a step of growing on the GaN substrate principal face an at least single-lamina semiconductor layer to form semiconductor devices in which the product S&#xd7;D of the area Sof the device principal faces, and the density D of the inversion domains is made less than 2.3.

Semiconductor device and method of its manufacture

Affords Group III nitride semiconductor devices in which the leakage current from the Schottky electrode can be reduced. In a high electron mobility transistor, a supporting substrateis composed of AlN, AlGaN, or GaN, specifically. An AlGaN epitaxial layerhas a full-width-at-half maximum of (0002) plane XRD of 150 sec or less. A GaN epitaxial layeris provided between the gallium nitride supporting substrate and the AlGaN epitaxial layer (0&#x3c;Y&#x2266;1). A Schottky electrodeis provided on the AlGaN epitaxial layer. The Schottky electrodeconstitutes a gate electrode of the high electron mobility transistor. The source electrodeis provided on the gallium nitride epitaxial layer. The drain electrodeis provided on the gallium nitride epitaxial layer

Group III nitride semiconductor device and epitaxial substrate

Flat, thin AlN membranes and methods of their manufacture are made available. An AlN thin film () contains between 0.001 wt. % and 10 wt. % additive atomic element of one or more type selected from Group-III atoms, Group-IV atoms and Group-V atoms. Onto a base material (), the AlN thin film () is formable utilizing a plasma generated by setting inside a vacuum chamber a sintered AlN ceramic containing between 0.001 wt. % and 10 wt. % additive atomic element of one or more type selected from Group-III atoms, Group-IV atoms and Group-V atoms, and with the base material having been set within the vacuum chamber, irradiating the sintered AlN ceramic with a laser.

Thin film of aluminum nitride and process for producing the thin film of aluminum nitride

A method of producing an AlGaN (0&#x3c;x&#x2266;1) single crystal of the present invention is directed to growing an AlGaN single crystal by sublimation. The method includes the steps of preparing an underlying substrate, preparing a raw material of high purity, and growing an AlGaN single crystal on the underlying substrate by sublimating the raw material. At the AlGaN single crystal, the refractive index with respect to light at a wavelength greater than or equal to 250 nm and less than or equal to 300 nm is greater than or equal to 2.4, and the refractive index with respect to light at a wavelength greater than 300 nm and less than 350 nm is greater than or equal to 2.3, measured at 300K.

[object Object]

Affords a GaN single-crystal mass, a method of its manufacture, and a semiconductor device and method of its manufacture, whereby when the GaN single-crystal mass is being grown, and when the grown GaN single-crystal mass is being processed into a substrate or like form, as well as when an at least single-lamina semiconductor layer is being formed onto a single-crystal GaN mass in substrate form to manufacture semiconductor devices, cracking is controlled to a minimum. The GaN single-crystal masshas a wurtzitic crystalline structure and, at 30&#xb0; C., its elastic constant Cis from 348 GPa to 365 GPa and its elastic constant Cis from 90 GPa to 98 GPa; alternatively its elastic constant Cis from 352 GPa to 362 GPa.

GaN single-crystal mass and method of its manufacture, and semiconductor device and method of its manufacture

There is provided a method for fabricating a gallium nitride crystal with low dislocation density, high crystallinity, and resistance to cracking during polishing of sliced pieces by growing the gallium nitride crystal using a gallium nitride substrate including dislocation-concentrated regions or inverted-polarity regions as a seed crystal substrate. Growing a gallium nitride crystalat a growth temperature higher than 1,100&#xb0; C. and equal to or lower than 1,300&#xb0; C. so as to bury dislocation-concentrated regions or inverted-polarity regionsreduces dislocations inherited from the dislocation-concentrated regions or inverted regions, thus preventing new dislocations from occurring over the dislocation-concentrated regions or inverted-polarity regions. This also increases the crystallinity of the gallium nitride crystaland its resistance to cracking during the polishing.

Growing community of inventors

Itami, Japan

Takashi Sakurada