Hidetoshi Oka

Growth of ZnSe single crystals by iodine transport

Abstract Large ZnSe single crystals (14x14x20 mm3) have successfully been grown from the vapor phase by iodine transport. Substrates with large area (10x10 mm2) for epitaxial growth were prepared by cutting the crystal. It is important to control the temperature fluctuation and seed direction for rapid growth. As an etchant for the measurement of dislocation density, the NaOH solution on (111)B is better than the Br-CH3OH solution on (111)A. The etch-pit density is (2–7)x104/cm2. The iodine concentration in the crystal is about 200 ppm. The resistivity of the ZnSe crystal annealed in molten Zn is 0.03 Ω cm.

Epitaxial Growth of High Quality ZnSe on GaAs Substrate by Atmospheric Pressure MOVPE Using Dimethylzinc and Hydrogen Selenide

Single crystalline layers of undoped ZnSe have been grown on GaAs substrates by atmospheric pressure MOVPE using dimethylzinc (DMZ) and hydrogen selenide (H2Se). Premature reactions typically encountered with this source combination can be eliminated completely, even at atmospheric pressure, by controlling the flow velocity of each source gas and the source gas mole ratio. For the first time, an excellent mirror surface morphology, as revealed by Nomarski interference microscopy, was obtained even for 8.2 µm thick epilayers grown at 300°C.