Electrical study on indium-rich InGaN/GaN multi-quantum-well system

Abstract

We studied the electrical properties of a 10-period InGaN/GaN multi-quantum-well (MQW) structure by using capacitance-voltage (C-V) and deep-level transient spectroscopy (DLTS) methods. Two energy states of the InGaN QW appeared, are at about 0.37 eV and the other at 0.43 eV from the conduction band edge of the GaN barrier. Band-to-band transition energies of 3.10 eV and 3.18 eV were found by using the PL measurements. A defect with an activation energy of 0.39 eV and a cross-section of 3.96 × 10-18 cm 2 was also found in the GaN buffer layer. The energy-band diagram of InGaN/GaN QW structure is discussed using the PL and the DLTS parameters, considering the existence of a electron capture barrier.