ABSTRACTIn this paper we report a modified Kroemer's analysis for the determination of the band offset (ΔEc) of single quantum well (SQW) structures from simple C-V measurements. The experimental carrier profile from an MOVPE grown pseudomorphic GaAs/InGaAs/GaAs strained SQW structure shows a sharp accumulation peak bounded by depletion regions on either side. The full width at half maximum of the accumulation peak is comparable to the width of the quantum well. The value of ΔEC obtained from C-V measurement is in good agreement with the values determined by simulation and photoluminescence measurements. DLTS measurements on our SQW samples do not show any peaks which is contrary to the published reports. We believe that it is necessary to carefully isolate the role of interface states, before assigning a DLTS peak to emission from the quantum well.
MEASUREMENT OF THE BAND OFFSET IN GexSi1-x/Si SINGLE QUANTUM WELL BY USING SINGLE FREQUENCY ADMITTANCE SPECTROSCOPY
