摘要:
A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
摘要:
A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
摘要:
A production method of a GaN-based compound semiconductor having excellent crystallinity and a GaN-based semiconductor device produced therefrom. A discrete SiN buffer body is formed on a substrate, and a GaN buffer layer is formed thereon at low temperatures and a GaN semiconductor layer is then formed at high temperatures. By forming the discrete SiN buffer body, the crystal growth, which is dependent on the substrate, of the low-temperature buffer layer is inhibited and monocrystallization is promoted to generate seed crystals used at the time of growing the GaN buffer layer. Further, by forming SiO2 discretely between the substrate and the SiN buffer body or by forming InGaN or a superlattice layer on the GaN semiconductor layer, distortion of the GaN semiconductor layer is reduced.
摘要:
The electron multiplying device according to this invention comprises an electron multiplying unit including dynodes arranged in a plurality of stages. The electron multiplying unit has an incidence opening for an energy beam to be multiplied to enter through, and has the proximal end secured to a base. There is provided a casing for housing the electron multiplying unit. The forward edge of the casing is secured to the base, and a space defined by the base and the casing houses the electron multiplying unit. The casing has an entrance window formed at a position opposed to the incidence opening. Energy beams enter the electron multiplying unit through the entrance window, but the electron multiplying unit itself is housed in the casing to be protected from surrounding air flow and unnecessary energy beams not to be measured.
摘要:
A semiconductor wafer having an epitaxial GaAs layer, including a monocrystalline Si substrate having a major surface which is inclined at an off angle between 0.5.degree. and 5.degree. with respect to (100); and at least one intermediate layer epitaxially grown on the major surface of the monocrystalline Si substrate, as a buffer layer for accommodating a lattice mismatch between the Si substrate and the epitaxial GaAs layer which is epitaxially grown on a major surface of the top layer of the at least one intermediate layer. The at least one intermediate layer may comprise one or mor GaP/GaAsP, GaAsP/GaAs superlattice layers. the wafer may be used to produce a seimconductor light emitting element which has a plurality of crystalline gaAs layers including a light emitting layer epitaxially grown on the GaAs layer on the intermediate layer. The wafer may also be used to produce a compound semiconductor device such as amplifying and switching elements, light emitting and receiving elements and photovolataic elements. Methods for producing the semiconductor wafer, light emitting element and compound semiconductor devices are also disclosed.
摘要:
Water-soluble high molecular weight polymers, useful as coagulating agents, are prepared by initiating the polymerization of acrylamide or a monovinyl monomer mixture containing a predominant amount of acrylamide in an acetone-water mixture at a temperature of not lower than 5.degree.C but of lower than 25.degree.C in the presence of polyvinyl alcohol and a catalyst, the concentration of the monomer in the polymerization reaction mixture being 15 to 30 % by weight and the concentration of acetone in the acetone-water mixture being 15 to 35 % by weight, and continuing the polymerization reaction while controlling the viscosity of the reaction system by adding a water-miscible organic solvent having a small chain transfer coefficient to the reaction system with the progress of the polymerization reaction.