16.8 A/600 V AlGaN/GaN MIS‐HEMTs employing LPCVD‐Si ₃ N ₄ as gate insulator

Abstract

An AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor (MIS-HEMT) on Si substrate was obtained with 18 nm silicon nitride (Si 3 N 4) grown by low-pressure chemical vapour deposition (LPCVD) as the gate insulator. The D-mode MIS-HEMT shows a high I dss of 16.8 A at V g = 3 V, a high breakdown voltage (BV) of 600 V and a low-specific on-resistance of 2.3 mΩ•cm 2. The power device figure of merit (FOM = BV 2 /R on,sp) is calculated as 157 MW•cm −2. The good insulation effects of LPCVD-Si 3 N 4 were also demonstrated by the low gate leakage current of 154 nA at V ds = 600 V and V gs = −14 V. Furthermore, an E-mode device was realised by a low-voltage silicon metal-oxidesemiconductor field-effect transistor in series; the V th was determined to be 2.6 V. The high I dss , low-specific on-resistance, high BV and positive V th show the potential and advantages of GaN MIS-HEMTs for power switching applications. BE2013002-2) and by the Jiangsu Science and Technology Support Program (grant no. BE2012079). We thank the Suzhou nanofabrication facility of SINANO, CAS, for the fabrication, characterisation and testing of the AlGaN/GaN MIS-HEMT.