Thermal-stability performance of a metamorphic high electron mobility transistor (MHEMT) with non-annealed Ohmic contacts

The temperature-dependent characteristics of the non-annealed Ohmic contacts InAlAs/InGaAs MHEMT are studied and demonstrated. Due to the use of Ohmic-recess technique, the improvements on device performance including higher saturation drain current, higher transconductance, lower on-resistance, lower parasitic resistance, more linear operating regime, and superior microwave performance are obtained. The non-annealed Ohmic contacts device also shows good properties at higher operating temperature regime and the relatively thermal stable performance over the operating temperature range (300–500 K). Therefore, the studied device with non-annealed Ohmic contacts process provides the promise for high-temperature and high-performance microwave electronic device applications.