Preliminary reliability at 50 V of state-of-the-art RF power GaN-on-Si HEMTs

In this paper, state-of-the-art 1 mm RF power GaN-on-Si HEMTs using thick in-situ grown SiN cap layer are presented. Output power density POUT exceeding 10 W/mm is reproducibly achieved above 50 V drain voltage while still limited by thermal issues. In order to assess the device stability, the GaN-on-Si HEMTs have been tested at high channel temperature (> 300°C) and under high electric field (V_DS = 50 V). The results demonstrate for the first time the possibility to combine extremely high RF output power density at V_DS = 50 V with high reliability using a cost-effective technology.