Abstract
We have observed a chopping frequency dependence of the photoreflectance (PR) spectra of the MQW structure : GaAs/AlAs multiple-quantum-well (MQW)/GaAs buffer/semi-insulating GaAs substrate. The PR spectra obtained from the GaAs buffer layer and the MQW reveal different frequency dependences. It is found that the buffer/MQW interface states or deep levels in the buffer control the frequency dependence of the modulating field that exist in the buffer. It is finally shown that the PR technique is a powerful tool for characterizing deep levels in the MQW or SL structures grown on semi-insulating materials as compared to the deep level transient spectroscopy (DLTS) method which cannot be applied in these cases.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
