Abstract: An epitaxial semiconductor wafer characterized by making the P-N junction face which having either flat or uneven face in a manner of uniformed thickness from the top surface, due to making a P or N type first layer by the Chemical Vapor Deposition on the basic plate and also to making a N or P type secondary layer on said first layer, while both of the layers being highly and pure controlled silicon, and the light reflectors being located at the out side of said each P or N type layer for concentrating the incoming light to the P-N junction portion.

Abstract: A method and apparatus of producing a crystal by using of vapor growth process, wherein: a high-frequency coil or conductor having a coil or conductor surface to generate a plane-like induction electric field is arranged so that at least one gas blowout port is connected to the coil or conductor surface so as to face a solid substrate; and a component element or a chemical compound is continuously precipitated and grown on a surface of the solid substrate at a temperature of not higher than the melting point of the solid substrate while the solid substrate is inductively heated by the high-frequency coil or conductor and a raw gas is supplied onto the surface of the solid substrate through the gas blowout port, to thereby produce a polycrystal or monocrystal thin film.

Abstract: A apparatus for manufacturing crystals through a floating zone method which includes: structure for forming a heat-melt zone so as to be held at an upper portion of a solid crystal; a barrier enclosure having an opening a lower end portion and provided in the vicinity of an upper surface of the heat-melt zone; structure for supplying a raw material granular crystal into the barrier enclosure; and structure for moving the solid crystal and the heat-melt zone forming structure relative to each other to thereby bring about crystal growth, wherein the barrier enclosure has a bottom surface being flat or inclined toward the center of the barrier enclosure, and wherein the opening is constituted by at least one hole formed in the bottom surface of the barrier enclosure.

Abstract: An engine control system corrects an air-fuel ratio of an air and fuel mixture during feedback control in a feedback region of engine operating conditions and during a learning control in a learning region of engine operating conditions. A purge region of engine operating conditions, in which purging of fuel vapor into the engine is conducted, is defined so as to have a portion overlapping with the learning control region. The air-fuel learning and the fuel vapor purging are conducted alternately. A specific region of engine operating conditions is defined in the purge region for higher flow rates of intake air. The control system undergoes the air-fuel learning prior to the fuel vapor purge when engine operating conditions are in this specific region.