Denso Corporation

Koichi Hoshino

Akihisa Fujita

Tetsuya Katayama

Takashi Taguchi

Teruaki Kohara

An antenna section is housed in a housing space which is defined by a radome and a housing, and provided with a transmitting antenna that transmits radar waves composed of radio waves of a predetermined frequency and a receiving antenna that receives the radar waves. The radome has a transmission section that is a portion transmitting the radar waves and an attenuation section that is a portion attenuating the radar waves. The attenuation section includes a first attenuation layer formed of a material for attenuating the radar waves. The first attenuation layer has a thickness that is 2n&#x2212;1 times (n is a natural number) of one-quarter of a wavelength of the radar waves in the first attenuation layer.

Radar apparatus provided with radome

An insulating layer is formed on a semiconductor substrate, and a first resist layer having a first resist opening portion is formed on the insulating layer. Then, the insulating layer is etched thought the opening portion to expose the substrate. After removing the first resist layer, a second resist layer having second resist opening portions are formed. One of the second resist opening portions is provided to expose the substrate, and a recess is formed in the substrate through the opening portion. Further, the insulating layer exposed from the other of the second resist opening portions is removed. Then, an electrode member for gate, source, and drain electrodes is deposited on the substrate. As a result, variations in intervals between the gate and drain electrodes and between the gate and source electrodes can be reduced.

Method of producing a MESFET semiconductor device having a recessed gate

A semiconductor device includes a semi-insulating substrate. A channel layer is formed on the semi-insulating substrate. An electron supply layer is formed on the semi-insulating substrate for generating a two-dimensional electron gas. The electron supply layer includes a doped superlattice layer. The superlattice layer includes layers of In.sub.X Al.sub.1-X As and layers of In.sub.Y Al.sub.1-Y As which alternate with each other, where 0.ltoreq.X.ltoreq.1.0 and 0.ltoreq.Y.ltoreq.1.0, and X differs from Y.

Growing community of inventors

Obu, Japan

Koichi Hoshino