Deep level transient spectroscopy study of energy levels in InAs/GaAs self-assembled quantum dots

Abstract

The energy states in InAs/GaAs self-assembled QD system were measured and analyzed by using capacitance-voltage and deep level transient spectroscopy methods with varying the applied biases and the filling pulse widths. The activation energies of the QD signals were shifted from 0.07 to 0.60 eV by changing the measurement biases, and then these results represent that the QD has many kind of confined energy levels. From the DLTS measurements with varying the filling pulse widths, it was confirmed that the QD has band-like interacting energy levels.