Oki Electric Industry Co., Ltd.

Toshio Nonaka

Kazuhiro Watanabe

Keisuke Shinozaki

Toshimasa Ishida

Katsuzo Kaminishi

Choho Yamagishi

An element for generating second-harmonic waves of a short wavelength from a fundamental wave emitting from a semiconductor laser and the like. The element includes a substrate made of a ferroelectric crystal, a second-harmonic wave generator for generating a second-harmonic wave from a fundamental wave entered therein, and periodically arranged portions formed in a front stage region and a rear stage region of the element. The periodic portions or structures, each have pairs of parts or regions of a high optical refractive index and of a low optical refractive index so as to confine the fundamental waves in the second-harmonic wave generating portion. These regions have various kinds of material diffused or introduced therein and of a thickness. According to another example of the element, the sign of a nonlinear optical coefficient of the region is periodically reversed and the region satisfies a quasi-phase-matching condition.

Second-harmonic wave generating element

A semiconductor device and a method of manufacturing the same are disclosed. The device comprises a GaAs semiconductor body, a source and a drain region formed in the semiconductor body, a channel region placed between the source and drain regions, a source and a drain electrodes provided by patterning treatment onto the surfaces of the source and drain regions and making ohmic contact thereto, and a gate electrode provided onto the surface of the channel region and consisting of a W-Al alloy. The method comprises steps of providing a GaAs semiconductor body as a substrate, forming an active layer into the body, forming a pattern of a W-Al alloy as a gate electrode, implanting donor ion with high concentration into a region including a portion of the active layer other than the underlying region of the portion on which the gate electrode is at least provided thereby forming a source and a drain region, subjecting the semiconductor body to an annealing treatment to activate the active layer and the source and drain regions, and providing ohmic contacts onto the source and drain regions.

Schottky barrier gate FET including tungsten-aluminum alloy

A method of manufacturing a GaAs compound semiconductor device is disclosed. The method comprises steps of applying a Ge film on an n+ region for forming ohmic electrode thereon, injecting impurity ion into the Ge film with high concentration, applying metal of high melting point overall surface of the semiconductor body to an annealing treatment after final ion implantation step.

Growing community of inventors

Tokyo, Japan

Toshio Nonaka