Intersubband Transition-Based Processes and Devices in AlN/GaN-Based Heterostructures (original) (raw)

1.37 - 2.90 Micron Intersubband Transitions in GaN/AlN Superlattices

MRS Proceedings, 2006

ABSTRACT Intersubband transitions in the spectral range of 1.37-2.90 °Cm is observed in molecular beam epitaxy grown Si-doped GaN/AlN multiple quantum wells using a Fourier-transform spectroscopy technique. A blue shift in the peak position of the intersubband transition is observed as the well width is decreased. A sample with a well width in the order of 2.4 nm exhibited the presence of three bound states in the GaN well. The bound state energy levels are calculated using a transfer matrix method. An electrochemical capacitance voltage technique is used to obtain the three dimensional carrier concentrations in these samples which further enable the calculation of the Fermi energy level position. Devices fabricated from these GaN/AlN quantum wells are found to operate in the photovoltaic mode.