The Inverse Piezoelectric Effect (IPE) is thought to contribute to possible device failure of GaN High Electron Mobility Transistors (HEMTs). Here we focus on a simulation study to probe the possible mitigation of the IPE by reducing the internal electric fields and related elastic energy through the use of high-k materials. Inclusion of a HfO2 "cap layer" above the AlGaN barrier particularly with a partial mesa structure is shown to have potential advantages. Simulations reveal even greater reductions in the internal electric fields by using "field plates" in concert with high-k oxides
Original Publication Citation
Nagulapally, D., Joshi, R. P., & Pradhan, A. (2015). Simulation study of HEMT structures with HfO2 cap layer for mitigating inverse piezoelectric effect related device failures. AIP Advances, 5(1), 1-12. doi: 10.1063/1.4905702
Nagulapally, Deepthi; Joshi, Ravi P.; and Pradhan, Aswini, "Simulation Study of HEMT Structures With HfO2 Cap Layer For Mitigating Inverse Piezoelectric Effect Related Device Failures" (2015). Electrical & Computer Engineering Faculty Publications. 75.