Abstract: According to one embodiment, a high-frequency switch includes a high-frequency switch IC chip. The high-frequency switch IC chip has a high-frequency switching circuit section including an input terminal, a plurality of switching elements, a plurality of high-frequency signal lines, and a plurality of output terminals. The input terminal is connected to each of the plurality of output terminals via each of the plurality of switching elements with the high-frequency signal lines having the same lengths. The plurality of output terminals are arranged on a surface at an outer periphery of the high-frequency switch IC chip. The input terminal is arranged on the surface of the high-frequency switch IC chip at the center of the high-frequency switch IC circuit section.

Abstract: According to one embodiment, a high-frequency switch includes a high-frequency switch IC chip. The high-frequency switch IC chip has a high-frequency switching circuit section including an input terminal, a plurality of switching elements, a plurality of high-frequency signal lines, and a plurality of output terminals. The input terminal is connected to each of the plurality of output terminals via each of the plurality of switching elements with the high-frequency signal lines having the same lengths. The plurality of output terminals are arranged on a surface at an outer periphery of the high-frequency switch IC chip. The input terminal is arranged on the surface of the high-frequency switch IC chip at the center of the high-frequency switch IC circuit section.

Abstract: A heterojunction type compound semiconductor field effect transistor includes a channel layer, a first electron supply layer, an electric field strength reducing layer, a first contact layer, a recess stopper layer, and a second contact layer sequentially stacked on a compound semiconductor substrate. This transistor has a double recess structure. The first contact layer is composed of GaAs or InGaAs doped with n type impurities with a high electron mobility. The electric field strength reducing layer is composed of intrinsic InGaP.

Abstract: A heterojunction type compound semiconductor field effect transistor includes a channel layer, a first electron supply layer, an electric field strength reducing layer, a first contact layer, a recess stopper layer, and a second contact layer sequentially stacked on a compound semiconductor substrate. This transistor has a double recess structure. The first contact layer is composed of GaAs or InGaAs doped with n type impurities with a high electron mobility. The electric field strength reducing layer is composed of intrinsic InGaP.

Abstract: A high-gain monolithic antenna with high freedom of design has a signal circuit and a stripline dipole antenna which are provided on a substrate. A dielectric film and a conductor cover covering the dielectric film are provided on the upper surface of the substrate, in addition to a hole extending vertically downward to the underside of the substrate, a conductor wall being provided on the surface thereof. Furthermore, a metallic film is evaporated so as to contact both a metallic cover and a conductor wall. A first grounding conductor and a dielectric are provided on the lower surface of the substrate, and a second grounding conductor is provided on the upper surface of the substrate. A horn, which is tapered into the dielectric and the first grounding conductor thereby forming the shape of a quadrangular pyramid, is provided so as to overlap a hole etched into the substrate. Microwaves or milliwaves are radiated to/from the horn to/from the underside of the substrate.

Abstract: A semiconductor device has an active layer formed on a semiconductor substrate with different types of junctions, a source region, a drain region, a T-shaped gate electrode in which the cross-sectional area of the upper surface is larger than that of the lower surface, a first dielectric layer covering at least the exposed surface of the active layer, and the gate electrode, and a second dielectric layer enclosing the first dielectric layer. In the device, when the specific inductive capacities of the first and second dielectric layers are .epsilon.(1) and .epsilon.(2) respectively .epsilon.(1)<.epsilon.(2) and the water absorption ratio of the first dielectric layer is greater than the water absorption ratio of the second dielectric layer.

Abstract: According to this invention, there is provided a method of manufacturing a compound semiconductor which can be formed at a high yield and in which variations in characteristics of elements caused by variations in distances between a source and a gate and between a drain and the gate can be minimized. In addition, there is provided a compound semiconductor device having a structure capable of increasing a power gain and obtaining a high-speed operation. According to this invention, an active layer is formed on a compound semi-conductor substrate, and source/drain electrodes are formed on the active layer to be separated from each other. The wall insulating films are respectively formed on side walls of the electrodes, and a gate electrode is formed between the side wall insulating films to be respectively in contact therewith.