Abstract:

This work proposes a multi-metal gated architecture to improve the linearity of AlGaN/GaN high electron mobility transistor (HEMT). The general idea of this architecture is to use different gate metals along the width of the device. Through experimentally calibrated technology computer-aided design (TCAD) simulation, a selection of metals along with widths that yields the lowest value of third-order transconductance (gm3) has also been estimated. Single tone large signal simulation of proposed de- vice exhibits output-referred 1dB compression point (P1dB) of 1.81 W/mm, saturation output power (Psat) of 6.91 W/mm, and maximum power added efficiency (PAE) of 65%, all of which are better than simulations of standard/baseline device structures. Two-tone large signal simulation shows excellent linearity performance when biased at deep class AB showing OIP3/PDC of 13.7 dB which is 6.3 dB higher and IMD3 of −45.7 dBc which is 12.9 dB lower than baseline device at VDS,Q = 28 V, ID,Q = 73 mA/mm. These performance matrices attest to the improved linearity performance of the proposed device compared to conventional planar Al- GaN/GaN HEMT.