Abstract: Provided is a cadmium zinc telluride (CdZnTe) single crystal including a main surface that has a high mobility lifetime product (?? product) in a wide range, wherein the main surface has an area of 100 mm2 or more and has 50% or more of regions where the ?? product is 1.0×10?3 cm2/V or more based on the entire main surface, and a method for effectively producing the same.

Abstract: Provided is an indium phosphide substrate having good accuracy of flatness of the orientation flat, and a method for producing the indium phosphide substrate. An indium phosphide substrate having a main surface and an orientation flat, wherein a difference between maximum and minimum values of a maximum height Pz in each of four cross-sectional curves is less than or equal to 1.50/10000 of a length in a longitudinal direction of an orientation flat end face, wherein the four cross-sectional curves are set at intervals of one-fifth of a thickness of the substrate on a surface excluding a width portion of 3 mm inward from both ends of the orientation flat end face in the longitudinal direction of the orientation flat end face, and the maximum height Pz in each of the four cross-sectional curves is measured in accordance with JIS B 0601:2013.

Abstract: Provided is an indium phosphide substrate having good linearity accuracy of a ridge line where the main surface is in contact with the orientation flat, and a method for producing the indium phosphide substrate. An indium phosphide substrate having a main surface and an orientation flat, wherein a maximum value of deviation is less than 1/1000 of a length of a ridge line where the main surface is in contact with the orientation flat, when a plurality of measurement points are set at intervals of 2 mm from a start point to an end point at the ridge line, except for a length portion of 3 mm inward from both ends of the ridge line, and based on a reference line which is a straight line connecting the start point and the end point, a distance of each measurement point from the reference line is defined as the deviation of each measurement point.

Abstract: Provided is a cadmium zinc telluride (CdZnTe) single crystal including a main surface that has a high mobility lifetime product (?? product) in a wide range, wherein the main surface has an area of 100 mm2 or more and has 50% or more of regions where the ?? product is 1.0×10?3 cm2/V or more based on the entire main surface, and a method for effectively producing the same.

Abstract: A surface of the single crystal wafer 5 for semiconductor laser having an orientation flat formed by cleaving is polished by using the abrasive cloth 8 with high hardness under the optimized pressure for pushing the wafer and polishing rate, such that the polishing rate on the whole surface of the respective wafer 5 becomes uniform. The facet roll-off D occurred at a ridge of a cleavage surface 4 of the single crystal wafer 5 for semiconductor laser to be equal to or less than 40 ?m. The single crystal wafer for a semiconductor laser of the present invention can provide an improvement in a precision of an optical alignment of mask pattern using the cleavage surface as a reference, and an improvement in process yield.

Abstract: A Si-doped gallium arsenide single crystal substrate has a carrier concentration of 0.1×1018 to 5.0×1018/cm3. The substrate is made by Vertical Bridgeman (VB) method or Vertical Gradient Freeze (VGF) method, and a minimum value and a maximum value of the carrier concentration in substrate plane are within a dispersion of 10% or less of an average carrier concentration in substrate plane.

Abstract: A p-type GaAs single crystal containing Si, Zn, B and In as dopants has an average dislocation density of 100 cm?2 or less. It may be produced by cooling a GaAs melt containing Si, Zn, B and In as dopants in a crystal-growing container having a seed crystal placed at a lower end thereof in an upward increasing temperature gradient, to cause a single crystal to grow upward from the seed crystal.

Abstract: A surface of the single crystal wafer 5 for semiconductor laser having an orientation flat formed by cleaving is polished by using the abrasive cloth 8 with high hardness under the optimized pressure for pushing the wafer and polishing rate, such that the polishing rate on the whole surface of the respective wafer 5 becomes uniform. The facet roll-off D occurred at a ridge of a cleavage surface 4 of the single crystal wafer 5 for semiconductor laser to be equal to or less than 40 ?m. The single crystal wafer for a semiconductor laser of the present invention can provide an improvement in a precision of an optical alignment of mask pattern using the cleavage surface as a reference, and an improvement in process yield.

Abstract: A Si-doped gallium arsenide single crystal substrate has a carrier concentration of 0.1×1018 to 5.0×1018/cm3. The substrate is made by Vertical Bridgeman (VB) method or Vertical Gradient Freeze (VGF) method, and a minimum value and a maximum value of the carrier concentration in substrate plane are within a dispersion of 10% or less of an average carrier concentration in substrate plane.

Abstract: A method for growing a compound semiconductor single crystal comprising cooling a starting material melt of a compound semiconductor with an upward increasing temperature gradient in a crystal-growing container having a seed crystal placed at a lower end, thereby growing a single crystal upward from the seed crystal, the crystal orientation of the seed crystal in a crystal growth axis direction being an offset orientation of <100>+?, wherein the offset angle ? is 2°???55°.

Abstract: A p-type GaAs single crystal containing Si, Zn, B and In as dopants has an average dislocation density of 100 cm−2 or less. It may be produced by cooling a GaAs melt containing Si, Zn, B and In as dopants in a crystal-growing container having a seed crystal placed at a lower end thereof in an upward increasing temperature gradient, to cause a single crystal to grow upward from the seed crystal.

Abstract: A method for growing a compound semiconductor single crystal comprising cooling a starting material melt of a compound semiconductor with an upward increasing temperature gradient in a crystal-growing container having a seed crystal placed at a lower end, thereby growing a single crystal upward from the seed crystal, the crystal orientation of the seed crystal in a crystal growth axis direction being an offset orientation of <100>+&thgr;, wherein the offset angle &thgr; is 2°≦&thgr;≦55°.

Abstract: This invention relates to fabrication of a single crystal of a compound semiconductor according to the vertical Bridgman method which improves a recess in the interface between solid and melt and can obtain a stable yield of single crystal growth characterized in that a part for discharging the heat of a crucible to the outside in the radial direction is formed at least in a part in the circumferential direction of a heater part for controlling the interface between solid and melt in a heater which surrounds the crucible and a semiconductor melt is gradually solidified from a lower part to an upper part in the crucible while maintaining the interface between solid and melt in a saddle shape, thereby growing a single crystal.

Abstract: This invention relates to fabrication of a single crystal of a compound semiconductor according to the vertical Bridgman method which improves a recess in the interface between solid and melt and can obtain a stable yield of single crystal growth characterized in that a part for discharging the heat of a crucible to the outside in the radial direction is formed at least in a part in the circumferential direction of a heater part for controlling the interface between solid and melt in a heater which surrounds the crucible and a semiconductor melt is gradually solidified from a lower part to an upper part in the crucible while maintaining the interface between solid and melt in a saddle shape, thereby growing a single crystal.

Abstract: This invention relates to fabrication of a single crystal of a compound semiconductor according to the vertical Bridgman method which improves a recess in the interface between solid and melt and can obtain a stable yield of single crystal growth characterized in that a part for discharging the heat of a crucible to the outside in the radial direction is formed at least in a part in the circumferential direction of a heater part for controlling the interface between solid and melt in a heater which surrounds the crucible and a semiconductor melt is gradually solidified from a lower part to an upper part in the crucible while maintaining the interface between solid and melt in a saddle shape, thereby growing a single crystal.