Hydrogen-terminated diamond FET and GaN HEMT delivering CMOS inverter operation at high-temperature

An increasing number of applications in power electronics, sensor signal conditioning, and RF communication are demanded to operate beyond 200°C (e.g., engine and geothermal wellbore monitoring). These applications require integrated circuits such as mixed-signal circuits featuring analog circuitry, analog to digital converters as well as embedded microcontrollers and on-chip memories. The Si-based complementary metal-oxide-semiconductor (CMOS) technology combining a P-type MOS (PMOS) and N-type MOS (NMOS) to achieve different logic functions is not reliable for stable and sustained operations at high temperatures (>125 °C) [1] . In this work, we report the successful development of a CMOS building block using wide bandgap (WBG) technology that demonstrated operations up to >350 °C. The CMOS was developed using two wide bandgap material systems known for their high-temperature capability: diamond and gallium nitride (GaN). The "PMOS" utilizes a hole channel FET achieved using a hydrogen-terminated diamond field-effect transistor (diamond FET) and the "NMOS" is made out of an electron channel GaN high electron mobility transistor (GaN HEMT) as shown in Figure 1 .