Limitation of Hot-Carrier Generated Heat Dissipation on the Frequency of Operation and Reliability of Novel Nitride-Based High-Speed HFETs

摘要

The experimental investigation of fluctuations is a source of information on fast and ultrafast processes responsible for HFET performance and damage. A novel fluctuation-based approach, based on hot-electron velocity fluctuations measured at a microwave frequency, is used for prediction of nitride HFET operation and failure. The following statements summarize the main results: (1) The resonance-type dependence of hot-phonon lifetime on 2DEG density is resolved from the electron velocity fluctuations; (2) The optimal density for ultrafast dissipation of the LO-mode heat is estimated for the 2DEG channels located in GaN and InGaAs; (3) The optimal 2DEG density depends on the supplied power; (4) The HFET degradation is slower and the operation is faster when the LO-mode heat is dissipated faster; (5) The signatures of plasmons are found in electron velocity fluctuations, hot-phonon lifetime, electron drift velocity, HFET cutoff frequency, HFET phase noise, and HFET damage; (6) The novel heterostructre is proposed, implemented, and tested for improved ultrafast decay of LO-mode heat; (7) The novel heterostructre is proposed, implemented, and tested for improved efficiency of light emitting diodes; and (8) The fluctuation-based approach is proposed for improved device performance and mitigated device damage.