POLARIZATION EFFECTS IN NITRIDE SEMICONDUCTOR HETEROSTRUCTURES

Abstract

Wide bandgap nitride semiconductors have recently attracted a high level of attention owing to their direct bandgaps in the visible to ultraviolet regions of the spectrum and favorable transport properties, coupled with large dielectric strengths which pave the way for excellent emitters, detectors, and power amplifiers. Owing to the ionic nature of these semiconductors coupled with the lack of inversion symmetry in the wurtzitic form, which is the more stable form, spontaneous polarization charge at heterointerfaces and piezoelectric polarization charge due to strain are induced. In this paper, following a description of these effects, their impact on sample modulation-doped structures and multiple quantum wells are discussed.