TIME-RESOLVED OPTICAL STUDIES OF NITRIDE SEMICONDUCTORS FOR ULTRAVIOLET LIGHT EMITTERS

摘要

Femtosecond time-resolved reflectivity and luminescence downconversion techniques have been employed in the study of carrier localization and recombination in Ⅲ-nitride bulk semiconductors and active regions for ultraviolet light emitters. In AlGaN, trapping and nonradiative recombination related to the interplay of shallow and deep states associated with alloy fluctuations and structural defects, respectively, have been studied as a function of both Al content and defect density. The effect of indium incorporation on carrier trapping at localized states and radiative efficiency has also been investigated. Finally, the importance of these issues for AlGaN and InAlGaN quantum wells are addressed.