Raman and Infrared Spectroscopy Studies on Wide Gap Semiconductor GaN,SiC,ZnO and Related Materials/Structures
<正>Research and developments on wide energy pap GaN,SiC and ZnO based semiconductors,related materials and quantum structures are very active in recent years. GaN-based quantum structural materials are promising for energy-saving and environmentally friendly solid-state light sources,SiC is recognizing as the 21th century power semiconductor and ZnO is expecting to play an important role for next generation optoelectronic and electronic devices. This presentation reports on our Raman and infrared spectroscopy studies on these materials and structures,in particular new results from the author and collaborators in recent years.The following significant research issues and results are given: i] UV-excitation(325 nm)resonance Raman scattering on p-type GaN,and the correlation of multiple LO phonons with p-doping characteristics; ii] Raman and resonance Raman scattering on p-type ZnO and semi-magnetic ZnMnO; iii] Temperature(T)dependent Raman and UV-excitation resonance Raman scattering on n-type SiC,revealing a unique T-behavior and folded phonons; iv] The phonon anisotropy property of GaN wurtzite crystal studied using the angular dependent Raman spectroscopy both theoretically and experimentally; v] Electronic Raman scattering of n-type GaN,LO phonon-plasmon interaction effects, combined differential scattering cross section of coupled modes due to the deformation potential electro-optical(DPEO)and the charge density fluctuation(CDF)mechanisms, complete theoretical models and simulations of the wave vector related model on wurtzite GaN and InN; vi] Infrared optical absorption of doped and undoped bulk SiC; vii] Infrared reflectance on defect features of ion-implanted SiC. Some more unsolved problems are raised,which are challenging our understanding to science,and hopeful to get hinds from discussion with expert audience.