Novel HEMT based on GaN on Diamond for High Power Amplifiers

GaN based HEMTs are capable of achieving high power density at high frequency. Thus, solid-state high power amplifiers based on GaN will be smaller and lighter than incumbent technology. The use of a silicon substrate for GaN HEMTs provides a reliable GaN device which is also economical. MMICs based GaN on Si are ideally suited for applications in X-band radar systems that are part of the ballistic missile defense system developed by the MDA. The performance and reliability of GaN HEMTs is closely linked to the operating temperature. In this proposal, we will develop a novel GaN on diamond based HEMT structure with superior thermal conductivity relative to conventional approaches. In addition to significantly improving the thermal resistance, we will develop a novel process pathway that is inherently manufacturable and cost effective thus enabling the maximum usage of GaN technology for various military applications. In Phase I, we will demonstrate the feasibility of the material structure by performing iterative process development. In Phase II, we will focus on improving the maturity of the concept by further optimizing the process and by developing a functioning GaN on diamond HEMT device for evaluation of thermal and electrical performance.