Strain and charge distribution in GaN-AlN-GaN semiconductor-insulator-semiconductor structure for arbitrary growth orientation

• Published in: Applied physics letters 1993-10, Vol.63 (16), p.2243-2245
• Main Authors: BYKHOVSKI, A, GELMONT, B, SHUR, M
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in interface structures; Exact sciences and technology; Physics; Piezoelectric and electrostrictive constants; Piezoelectricity and electromechanical effects; Polarization and depolarization; Semiconductor-insulator-semiconductor structures
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.110540

We demonstrate that, in a GaN-AlN-GaN semiconductor-insulator-semiconductor structure, the strain-induced electric fields across the interface depend on the angle, θ, between the c axis and the growth direction. The magnitude of the strain induced polarization has a maximum in (0001) crystallographic direction (θ=0°) and a subsidiary maximum near θ=70°. This angular dependence is a unique feature of wurtzite-type structures. Considering θ as an independent parameter for device design, one can obtain structures with flat band voltage shift from 0 to 1.5 V for 30 Å AlN film, with different positions of accumulation-depletion regions, and with electron (hole) charge varying from 0 to more than 1012 cm−2.