Ga2Se3 films have been grown by molecular beam epitaxy. Single-crystal Ga2Se3 films were obtained for the first time on (001) GaP substrates at a substrate temperature of 550 °C and at a VI/III flux ratio greater than 15. Extra diffraction spots with weak intensity were observed in reflection high-energy electron diffraction patterns of the Ga2Se3 films grown at a VI/III ratio above 150. These extra spots were also observed in the transmission electron diffraction pattern. The extra points are attributed to the ordering of native Ga vacancies in the defect zinc blende structure.

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Gas source molecular-beam epitaxy (MBE) has been studied as a low-temperature Si and SiGe epitaxial method. Specular single-crystalline silicon films were successfully grown by the gas source Si MBE technique at a substrate temperature of about 650 °C. N-type doping was carried out using PH3 gas as a dopant and the maximum electron concentration of 2.9x1019cm−3 was obtained. Furthermore, p-type doping using B2H6 gas was carried out for the first time and the maximum hole concentration of 9.5×1017cm−3 was successfully achieved. The SiGe alloy layer was also grown by the gas source MBE technique using GeH4 as a Ge source gas. The Ge concentration of the sample could be precisely controlled by the molar fraction of Ge in supply and it was increased up to 0.30 with increasing the gas ratio of GeH4 to Si2H6.

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Growth of III-VI compound semiconductors (Ga2S3, Ga2Se3 and Ga2Te3) has been tried for the first time by metalorganic molecular beam epitaxy (MOMBE). The growth rate decreases with increasing substrate temperature, and single crystal Ga2Te3 films were obtained on (100) InP substrates. In Ga2Te3 growth, the lattice mismatch between Ga2Te3 and the substrate is critical in obtaining good epitaxial films.