Capacitance-voltage characteristics of quantum well structures

The characteristics of the apparent carrier distribution (ACD) of quantum w ell (QW) structures are investigated using the self-consistent simulation a nd the capacitance-voltage (C-V) profiling techniques. The simulation resul ts on the differential carrier distribution show that the change of positio n expectation value of two-dimensional electrons determines the full width at half maximum of 100 K ACD peaks when conduction band offset is Delta E-c =160 meV and the QW width t(w) is greater than 120 Angstrom. The contributi on of Debye averaging effects to the ACD peaks becomes important as t(w) an d Delta E-c values decrease and the temperature is increased. The influence of Debye averaging effects on ACD peaks appears differently according to t he location of each well in multiple QWs. These results indicate that the e xtraction of QW parameters from the C-V profile should be done with caution .