Electron transport properties in AlGaN/InGaN/GaN double heterostructures grown by metalorganic vapor phase epitaxy

摘要

Electron transport properties in AlGaN/InGaN/GaN double heterostructures have been investigated. Samples were grown by metalorganic vapor phase epitaxy and evaluated using x-ray diffraction and variable temperature Hall effect measurements. Much higher two-dimensional electron gas density of up to 50% has been obtained in AlGaN/InGaN/GaN structure than in a typical AlGaN/GaN structure due to the larger polarization effect while the mobilities are comparable at room temperature and above in these structures, which demonstrates the suitability of an AlGaN/InGaN/GaN structure for high-power device applications. Theoretical simulations were done to investigate the carrier transport mechanism, and they suggest that alloy disorder and interface roughness scattering have a very strong impact on the electron transport properties in AlGaN/InGaN/GaN structures.