Growth, characterization, and device applications of mixed-group-V alloys,InAsPSb and GaAsPSb
Hao-Hsiung Lin（Ph.D, Professor）
Dept. of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
InAsPSb and GaAsPSb consist of binaries with very different bond lengths. Though the lattice constant of the alloy follows Vegard’s law, the bond length does not. As a result, the alloys have strong internal bond distortion, leading to profound influence on the electronic and structural properties. We utilized molecular-beam epitaxy to deposit InAsPSb and metalorganic chemical deposition to deposit GaAsPSb. X-ray absorption extended fine structure and valence force field modelwere used to show that the bond lengths in InAsPSb are close to those in pure binaries and thebond distortion. The reason why bond distortion does not affect the linewidth of X-ray diffraction is also addressed. In addition, we found a considerable residual strain left in the InAsPSbgrown on GaAs, whose magnitude is proportional to the bond distortion energy, suggesting that the distortion could hinder the relaxation of the strained layer. The optical and electronic properties of GaAsPSb epilayer are also investigated using photo-luminescence and reflection measurement. Previous studies showed that the structural disorder resulting from bond distortion enhances the bowing of valence band, favoring the formation of type-II staggered band lineup. AnInGaP/GaAsPSb/GaAs heterojunction bipolar transistor with weakly type-II base-collector junction with low turn-on voltagewill be demonstrated in this talk.
Prof. Hao-Hsiung Lin received Ph.D. degree from National Taiwan University in 1985. He has been a professor with the Department of Electrical Engineering at National Taiwan University since 1992. His research interests are on the MBE growth of dilute nitrides, mid-infrared semiconductors, and nano-hetero-epitaxy of compound semiconductors. He has published more than 170 papers in reputed journals. Dr. Lin is a member of the Chinese Institute of Engineers and a senior member of IEEE.