Reliability of AlGaN/GaN HEMTs under DC- and RF-operation

In this work, device reliability under DC- and RF-operation at high temperatures ranging from 140°C to 200°C and at high drain voltage of 50 V has been achieved by improving the gate metal processing technology. It will be shown by long term stress tests that the gate processing technology is the key to improve the stability of the gate leakage current. The short term drain voltage robustness under off state condition has been examined by a DC-voltage-step-stress test. At the maximum drain voltage of 130 V the gate and drain current densities remain below 0.1 mA/mm. First RF stress test of a 2.4 mm power FETs at 2 GHz also shows little degradation.