Sumitomo Electric Device Innovations, Inc.

Shiseido Company, Limited

Senju Pharmaceutical Co., Ltd.

Hajime Matsuda

Tadashi Watanabe

Kenzo Ito

Yohei Hamano

Hideyuki Sumiyoshi

Yoshikazu Soyama

Takashi Minami

Noriko Tomita

Akio Nasu

Takayuki Miyazaki

Takashi Matsumoto

Osamu Uejima

Akio Taki

Yoshio Fujiyama

Yoshihiro Kanda

A process of forming a field effect transistor (FET) of a type of high electron mobility transistor (HEMT) reducing damages caused in a semiconductor layer is disclosed. The process carries out steps of: (a) depositing an insulating film on a semiconductor stack; (b) depositing a conductive film on the insulating film; (c) forming an opening in the conductive film and the insulating film by a dry-etching using ions of reactive gas to expose a surface of the semiconductor stack; and (d) forming a gate electrode to be in contact with the surface of the semiconductor stack through the opening, the gate electrode filling the opening in the conductive film and the insulating film.

Process of forming high electron mobility transistor (HEMT) and HEMT formed by the same

A process of forming a nucleus fanning layer in a nitride semiconductor epitaxial substrate is disclosed. The process includes steps of growing: a lower layer of the nucleus forming layer on a substrate; an upper layer of the nucleus thrilling layer on the lower layer; and a nitride semiconductor layer each by the metal organic chemical vapor deposition (MOCVD) technique. The growth of the nitride semiconductor layer is done at a temperature lower than a growth temperature for the upper layer, and the growth of the upper layer is done by supplying ammonia (NH) at a flow rate greater than the flow rate of ammonia (NH) timing the growth of the lower layer.

Process of forming epitaxial substrate and semiconductor device provided on the same

A process for forming a nitride semiconductor device is disclosed. The resulting semiconductor device includes a semiconductor stack with a top layer containing gallium (Ga) and nitrogen (N), electrodes of a source, a gate and a drain provided on the semiconductor stack, and a silicon nitride (SiN) film provided on the GaN layer between the drain electrode and the gate electrode but apart from the gate electrode. The SiN film has a silicon rich composition with a composition ratio of Si/N that is greater than &#xbe; and substantial oxygen contents.

Semiconductor device

A high electron mobility transistor (HEMT) includes a semiconductor layer on a substrate; an insulating film on the semiconductor layer; a gate electrode in contact with a surface of the semiconductor layer through an opening in the insulating film; and a conductive film provided between the insulating film and a portion of the gate electrode at peripheries of the opening. The insulating film and the conductive film are made of respective materials containing silicon (Si). The gate electrode includes a Schottky metal in contact with the semiconductor layer and a cover metal provided on the Schottky metal. The Schottky metal covers the conductive film thereunder.

A process of growing a barrier layer made of AlGaN on a GaN channel layer is disclosed. The process includes steps of, growing the GaN channel layer, growing the AlGaN barrier layer, and growing a cap layer made of GaN. The growth temperature of the AlGaN barrier layer monotonically lowers from the initial temperature, which may be equal to the growth temperature for the GaN channel layer, to the finish temperature that is lower than the initial temperature and may be substantially equal to the growth temperature of the GaN cap layer.

Process of forming semiconductor epitaxial substrate

A nitride semiconductor device is disclosed. The semiconductor device includes a semiconductor stack with a top layer containing gallium (Ga) and nitrogen (N), electrodes of a source, a gate and a drain provided on the semiconductor stack, and a silicon nitride (SiN) film provided on the GaN layer between the drain electrode and the gate electrode but apart from the gate electrode. The SiN film has a silicon rich composition with a composition ratio of Si/N that is greater than 3/4 and substantial oxygen contents.

A process of forming an epitaxial substrate that includes nitride semiconductor layers is disclosed. The process includes steps of; (a) growing a nucleus forming layer on the substrate, and (b) growing a nitride semiconductor layer on the nucleus forming layer. The step (a) sets first and second growth temperatures in an upstream side and a downstream side, respectively, of the substrate for the flow of the source gases, where the first temperature of the upstream side is at least 5&#xb0; C. but at most 10&#xb0; C. lower than the second temperature of the downstream side, and the second temperature is higher than 1100&#xb0; C.

Process of producing epitaxial substrate

A process of forming a semiconductor device by use of a MOCVD technique is disclosed. The semiconductor device, which is made of primarily nitride semiconductor materials, includes a GaN channel layer, an AlGaN barrier layer, and a GaN cap layer on a substrate. The barrier layer and the cap layer are grown under a gradient temperature condition where the upstream side of the substrate with respect to the flow of the MOCVD source gases is at a higher temperature as compared with the temperature at the downstream side of the substrate with respect to the flow of the source gases.

Process of forming nitride semiconductor layers

A semiconductor device having a via hole whose side surface is covered with nitride metal is disclosed. The via hole is formed within an insulating region that surrounds a conductive region, where both regions are made of nitride semiconductor materials. The via hole is filled with a back metal and in side surfaces thereof is covered with the nitride metal which is heat treated at a preset temperature for a preset period. Nitrogen atoms in the nitride metal diffuse into the nitride semiconductor materials in the insulating regions and compensate nitride vacancies therein. The interface between the nitride metal and the nitride semiconductor material is converted into an altered region that shows enough resistivity to suppress currents leaking from the via hole metal to the conductive region of the nitride semiconductor material.

Semiconductor device having via hole coated in side surfaces with heat treated nitride metal and method to form the same

A cholesterol ester clathrate comprising a cholesterol ester included in a hydroxyalkylated cyclodextrin; a hydrous composition comprising a hydroxyalkylated cyclodextrin, a cholesterol ester and water; a hydrous composition comprising a hydroxyalkylated cyclodextrin, a cholesterol ester, a hydrous stabilizer, and water; a hydrous composition comprising a hydroxyalkylated cyclodextrin, a cholesterol ester, a clay mineral, and water; cosmetics containing these hydrous compositions; and process for the preparation thereof. The clathrate exhibits an emulsifying effect in itself. Further, the hydrous compositions are excellent in water-holding capacity and are improved in hydration properties and separation stability at a high temperature.

Cholesterol ester clathrate, water-holding composition, hydrous compositions, cosmetics containing the same, and process for the preparation thereof

The invention provides a clathrate comprising a cyclodextrin or hydroxyalkylated cyclodextrin and, as included therein, dl-.alpha.-tocopheryl L-ascorbyl phosphate. In another aspect, the invention provides a dermal composition for external use, particularly a cosmetic composition. The composition is characterized by reduced foam production in aqueous solution and good stability against light.

Tocopheryl ascorbyl phosphate-cyclodextrin clathrate and a topical

Cholesterol ester clathrate, water-holding composition, hydrous

A cosmetic composition comprising an inclusion product having a slightly water-soluble component with a hydroxyalkylated cyclodextrin formulated therein.

Cosmetic composition containing inclusion product with hydroxyalkylated

A cosmetic stick having an excellent spreading property on human skin is prepared from a water-in-oil emulsion which comprises 1 to 50 weight % of water, 1 to 10 weight % of a polyhydroxy compound selected from glycerol, mannitol, dulcitol and carbohydrates, 1 to 5 weight % of an oleic acid esters of polyhydric alcohols and the balance consisting of a cosmetic base material.

Growing community of inventors

Yokohama, Japan

Hajime Matsuda