Characterization of a Zn_xCd_(1-x)Se/Zn_x'Cd_y'/Mg_(1-x'-y'),Se~y multiple quantum well structure for mid-infrared device applications by contactless electroreflectance and Fourier transform infrared spectroscopy

摘要

Contactless electroreflectance (CER) and Fourier transform infrared (FTIR) spectroscopy were used to study)he intersubband transitions of a ZnxCd'_xSejZnt,Cd"Mg'_x,_"Se mUltiple quantum well (MQW) structure grown by molecular beam epitaxy for mid-infrared device applications, The CER spectrum revealed a wide range of possible optical transitions in the MQW structure. The ground state transition was assigned by comparison with the photoluminescence emission signal taken from the same structure. A comprehensive analysis of the CER spectrum led to the identification of various interband transitions. The intersubband transitions were estimated and confirmed by FTIR measurements. The resuJts demonstrate the potential of using CER as a complementary technique for the contactless and nondestructive characterization of the wide band gap II-VI MQW structures for mid-IR intersubband device applications.