Abstract
Fourier-transform infrared (FTIR) spectra were studied to characterize the self-assembled InAs/GaAs quantum dot superlattices for long-wavelength infrared photodetectors. The superlattices, grown on (001)-oriented GaAs semi-insulating substrates by a solid-source molecular-beam epitaxy system, are composed mainly of 20 layers of Si-doped (5×1018 cm-3) InAs quantum dot layers and undoped GaAs spacer films. The composition, structural properties and surface morphologies of the InAs quantum dots were evaluated by secondary ion mass spectrometry (SIMS), transmission electron microscopy (TEM) and atomic force microscopy (AFM), respectively. The far-infrared absorption signals were observed using the FTIR technique. The analysis of FTIR absorption spectra revealed that the InAs quantum dot superlattices possess an unpolarized absorption feature and only a slight temperature-dependent change of absorption index.
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
