Investigation of Traps Impact on PAE and Linearity of AlGaN/GaN HEMTs Relying on a Combined TCAD-Compact Model Approach

This article proposes a novel modeling approach for the analysis of the microwave power performance of GaN HEMTs. By combining Technology Computer-Aided Design (TCAD) physical and circuit design standard compact trap models, surface and buffer traps can be directly correlated, for the first time, with power-added efficiency (PAE) and output power (P-out). A new trap model topology is created with an RC subnetwork and nonlinear scaling functions, encouraged by TCAD analysis on trap localization. The effects of surface trapping were quantified using a TCAD-based extraction of the proposed trap model, observing a loss on P-out of 3 dBm and a maximum PAE(PAE(MAX)) loss of 12% due to surface traps. In addition, the correlation of 2-D electron gas (2DEG) at the drain access region with PAE(MAX) and the 1-dB compression point of P-out(OP1 dB) is investigated and transformed into a correlation between the density of traps (N-T) and PAE(MAX )and OP1 dB,creating a new direct method to connect TCAD with RF large-signal simulations.