Authors: P. Martin, R. Hahe, L. Lucci
Affilation: CEA-Leti, France
Pages: 544 - 547
Keywords: AlGaN/GaN HEMTs, power transistor, compact model, surface potential
A new physics based compact model for III-nitride HEMTs developed for SPICE circuit simulation is presented. The HSP model (acronym for HEMT Surface-Potential model) follows a physical approach for power devices modeling, as it was done for advanced MOSFETs, leading to the development of compact models such as PSP, HiSIM and EKV3. We follow a surface-potential approach enabling continuous calculation of Fermi potential, drain current and charges. Several parameter dependencies are implemented such as: temperature, aluminum content, conduction band discontinuity, spontaneous and piezoelectric polarizations, layer thicknesses, AlxGa1-xN doping and incomplete donor activation observed in refractory III-nitride compounds. Other physical effects, like self-heating (SHE) and heat diffusion, which are important when the HEMT transistor works at high voltage, high current and high temperature are also modeled for the first time in a surface-potential based model. HSP is an interesting tool for technological development and optimization of AlGaN/GaN HEMTs. This physical approach allows also estimating the impact of technological variations on electrical performances (process variability). The model is implemented using Verilog-A.