Doctoral Thesis: GaN Electronics for High-Temperature Applications

Mengyang Yuan

Abstract:

Gallium nitride is a promising candidate for harsh environment electronics, thanks to its excellent material properties, which have given rise to high performance (room-temperature) transistors for RF, power, MEMS, and mixed-signal applications. Previous works on high temperature (HT) electronics have been typically limited to two aspects, namely, high temperature robustness of discrete transistors, and basic circuit building blocks, which are mainly combinational logic. While these studies offer strong indication of the potential of GaN transistor technology for HT applications, the development of HT (500 °C) GaN-ICs is still at its early stage due to the low degree of complexity and integration demonstrated so far. Major challenges in the realization of GaN HT-robust sequential logic circuits or more complex systems is the lack of a scalable technology. 
This thesis aims to advance the integration technology of GaN HT electronics by demonstrating a comprehensive HT (500°C) enhancement-mode (E-mode) GaN-on-Si technology from device to circuit perspectives: (1) a scalable device technology based on p-GaN-gate AlGaN/GaN HEMTs with high uniformity, which is optimized for HT operation and demonstrated to offer robust performance at least up to 500 °C with the help of in-house developed packaging technology and characterization platform, (2) compact modeling of monolithically integrated enhancement/depletion-mode HEMTs up to 500 °C HEMTs, (3) robustness-driven circuit design based on GaN technology, (4) demonstration of GaN-based combinational and sequential building blocks including inverter, NAND, NOR, ring oscillators, ROM, SRAM, D Latch, D Flip-Flop operational up to 500 °C.

Details

• Date: Tuesday, August 23
• Time: 12:00 pm - 2:00 pm
• Category: Thesis Defense
• Location: LOCATION CHANGED to 36-462 (Allen Room)

Additional Location Details:

Thesis Supervisor: Prof. Tomás Palacios