Enhancement Mode AlGaN/GaN MISHEMT on Ultra-Wide Band Gap β-Ga₂O₃ Substrate for RF and Power Electronics

A numerical simulation-based high-performance metal–insulator–semiconductor high electron mobility transistors (MISHEMTs) on an ultra-wide band gap β-Ga₂O₃ (E_g ~ 4.8 eV) substrate is presented. β-Ga₂O₃ (beta gallium oxide) has gained significant attention in radio frequency (RF) and power electronics applications. GaN HEMTs on β-Ga₂O₃ substrates are emerging HEMT technology for future RF and power electronics. Enhancement mode AlGaN/GaN MISHEMTs on β-Ga₂O₃ are proposed and analyzed for their DC and RF performance for L_g = 0.8 µm using ATLAS TCAD. A MISHEMT based on a SiN (Al₂O₃) insulator exhibited a high drain current density (I_DS) of 3.62 (3.7) A/mm, blocking voltage (V_BR) of 898 (1505) V, transconductance (g_m) of 1.09 (1.13) S/mm, and cut-off frequency (f_T) of 49 (44) GHz. Moreover, the proposed MISHEMT exhibited a very low on-resistance of 5 Ω mm. Combined with a higher cut-off frequency and high breakdown voltage, the proposed MISHEMT is suitable for future power switching and RF applications.