Strain energy band engineering approach to AlN/GaN/InN heterojunction devices

The authors' results clearly demonstrate that quaternary Al/sub x/In/sub y/Ga/sub 1-x-y/N layers can be used to improve the performance of heterojunction devices by controlling strain and/or lattice mismatch to GaN. They also demonstrated that In incorporation in the ternary layers significantly improves their structural and optical properties. The quaternary AlInGaN layers can be lattice matched either to GaN, AlGaN or AlInGaN by a proper selection of alloy compositions. This "strain energy band engineering" approach has allowed them to develop novel GaN-based transistors, UV LEDs, and solar blind photodetectors.