L G 55 nm T‐gate InGaN / GaN channel based high electron mobility transistors for stable transconductance operation

Abstract

Nonlinearity operation and early gain suppression limit the high-frequency operation of GaN-HEMTs. Nonlinear transconductance and resistance drop-off at relatively large VGS are the major sources for the nonlinear operation of the high electron mobility transistors (HEMTs). In this article, we present the In0.1Ga0.9N channel-based HEMTs for stable transconductance operation. The device performance is evaluated for both Al0.3Ga0.7N, and In0.17Al0.83N barrier materials with silicon nitride passivation. The In0.17Al0.83N/In0.1Ga0.9N/GaN heterostructure device shows remarkable improvement in gate voltage swing than Al0.3Ga0.7N/In0.1Ga0.9N/GaN. LG 55 nm T-gate In0.17Al0.83N/In0.1Ga0.9N HEMT exhibited 5 A/mm of maximum drain current density (IDS, max) for 1 V gate bias, 0.72 S/mm of stable transconductance (gm,max), 43.5 V of off-state breakdown voltage (VBR), and 275/289 GHz of fT/fmax. The HEMT with AlGaN/InGaN/GaN heterostructure showed 2.81 A/mm of maximum drain current density for 1 V gate bias, 0.66 S/mm of stable transconductance, 55.3 V of VBR, and 252/263 GHz of fT/fmax. Moreover, a highest theoretical OIP3 value of 61.2 and 67.6 dBm obtained for AlGaN and InAlN barrier HEMTs, respectively. The proposed InGaN/GaN channel-based HEMTs are more reliable for high-frequency linear operation.