Photonically-triggered SiC-GaN and Superjunction based High-gain, High-temperature, and High-voltage Bipolar Power Transistor

项目目标：1)利用低功率短波长光子源实现高增益、高压、高温单片SiC-GaN-OGBT（光门控双极晶体管）非锁存触发；2)利用GaN-SiC异质结结构优化光吸收效率，降低光子触发功率；3)利用局域电荷补偿和电导率调制降低OGBT导降；4)实验表征。知识优势：OGBT的发射极和基极由GaN制成，集电极由SiC制成，从而实现了光学效率，并保持了SiC优异的击穿电压和温度特性。OGBT消除了绝缘栅器件在高温和击穿电压限制下的氧化物可靠性问题。基于n型SiC衬底的OGBT结构规避了n通道SiC igbt所需的p型衬底不可用的问题。光触发OGBT消除了n衬底SiC IGBT的负栅极偏置参考需求。基于超结的SiC-GaN-OGBT电荷补偿技术可获得高阻断电压和低正向导通降。提出的工作探讨了连接N-GaN和P-SiC的欧姆接触问题以及GaN在SiC上的异质外延生长。由于光隔离、电磁干扰和寄生噪声抗扰性、器件应力缓解以及光子和宽带隙器件结构的协同集成，OGBT对高功率、高温和高频电源系统具有更高的可靠性。更广泛的影响：广泛的应用包括光控飞行、电动船舶、电动/混合动力汽车、电信、航天器、FACTs、脉冲功率和微波功率放大器。研究结果将被纳入两门本科/研究生课程。该项目将支持1名博士生，每年招收4名设计和本科研究生（包括2名弱势学生和1名优秀生）和1名中学生。

Project objectives are 1) Realizing a high-gain, high-voltage and high-temperature monolithic SiC-GaN-OGBT (optically-gated bipolar transistor) triggered in a non-latched manner using a low-power short-wavelength photonic source; 2) Reducing photonic-triggering power by optimization of optical-absorption efficiency using a GaN-SiC heterojunction structure; 3) Reducing OGBT conduction drop using localized charge-compensation and conductivity modulation; 4) Experimental characterizations.Intellectual Merit:The emitter and base of the OGBT are made of GaN while the collector is made of SiC, thus achieving optical efficiency and retaining excellent breakdown voltage and temperature characteristics of SiC. OGBT eliminates oxide-reliability problem at high temperature and breakdown-voltage limitation in insulated-gate devices. N-type SiC substrate-based OGBT structure circumvents the problem of unavailability of P-type substrate required for N-channel SiC IGBTs. Optical triggering of OGBT eliminates negative-gate-bias referencing need for N-substrate SiC IGBT. Superjunction-based charge-compensation technique in SiC-GaN-OGBT yields high blocking voltage and low forward-conduction drop. Proposed work explores ohmic-contact issues for connecting N-GaN to P-SiC and hetero-epitaxial growth of GaN on SiC. OGBT has implications for high-power, high-temperature, and high-frequency power system with enhanced reliability due to optical isolation, EMI and parasitic-noise immunity, device stress mitigation, and synergistic integration of photonic and wide-bandgap device structures. Broader Impacts:Broad applications include fly-by-light, electric ship, electric/hybrid vehicles, telecommunication, spacecrafts, FACTs, pulsed power, and microwave power amplifiers. The results of the research will be integrated into 2 undergraduate/graduate courses. The project will support 1 Ph.D. student and aims to incorporate, per year, 4 senior-design and undergraduate-research students (including 2 under-represented and 1 honor-role student), and 1 middle-school student.