SiC CMOS Integrated-Circuit High-Temperature Sensing Platform with Enhanced Gate Oxide Reliability

CoolCAD Electronics designs and fabricates silicon carbide (SiC) MOSFET electronic devices that have been shown to operate at 500°C. In addition, CoolCAD has demonstrated that its SiC CMOS circuits work for extended periods at hundreds of degrees C without obvious degradation.  CoolCAD Electronics is proposing to build on these successes to design and fabricate complex CMOS integrated electronic circuits which can operate reliably for long-term at 500°C, well beyond what conventional silicon electronics can withstand. Circuits to be built include analog-to-digital converters integrated with sensors and data registers, and digital circuits, such as gates, multiplexers, counters, adders and an arithmetic-logic unit (ALU). The proposed work also includes the design of a high-temperature SiC CMOS microprocessor. The effort also includes significant MOSFET device improvement, with a strong focus on gate oxide enhancement, guided by physics-based modeling, including quantum-mechanical simulations based on the Nobel Prize winning technique, Density Functional Theory. This unique approach aims to vastly improve the reliability of the gate oxide, which is the key feature of robust SiC CMOS electronics for both high and room temperature operation. Furthermore, specifically using CMOS electronics technology, as opposed to other transistor types, will allow for very large-scale integration (VLSI) of circuits for high temperature applications, in a way analogous to how silicon CMOS has enabled expansive scaling for electronics operating at standard temperatures. To verify robust, high-temperature long-term operation, CoolCAD is proposing to expand its high temperature testing facility. In order to enable routine tests and qualification of SiC CMOS electronic components at very high temperatures, CoolCAD will customize an environmental chamber with feedthrough wiring.  This equipment will allow for continuous and automated high-temperature circuit evaluation.  CoolCAD will address the issue of high-temperature-qualified electronic packaging and printed circuit board (PCB) attachment in collaboration with the world’s leading developer and manufacturer of solder reflow ovens for PCBs.  Also addressed in this proposal are the plans to commercialize CoolCAD’s SiC high temperature CMOS process methodologies and circuit designs by leveraging its current relationship with a commercial SiC fabrication facility. CoolCAD will work with this commercial facility in the USA to implement CoolCAD’s patent-protected SiC CMOS high temperature process in a mass-production setting. CoolCAD’s plans for a Phase 2-Option include extending their design and fabrication to very complex integrated CMOS circuits, including ALUs and memory circuits, that will form the building blocks of the world’s first very high temperature microprocessor. In the Phase 2-Option, CoolCAD will also fully qualify its new high temperature CMOS circuits for use in the government and private sectors.