Ionic Metal–Oxide TFTs for Integrated Switching Applications

Disordered ionic-bonded transition metal oxide thin-film transistors (TFTs) show promise for a variety of dc and RF switching applications, especially those that can leverage their low-temperature, substrate-agnostic process integration potential. In this paper, enhancement-mode zinc-oxide TFTs were fabricated and their switching performance evaluated. These TFTs exhibit the drain-current density of 0.6 A/mm and minimal frequency dispersion, as evidenced by dynamic current–voltage tests. A high-frequency power switch figure of meritR_ ONQGof 359mΩ \,· \,nC was experimentally determined for 0.75-μ mlong-channel devices, and through scaling 45.9mΩ \,· \,nC is achievable for 11 V-rated devices (whereRONis ON-state drain–source resistance, andQGis gate charge). An RF switch cutoff frequencyfcof 25 GHz was measured for the same 0.75-μ mTFT, whereasfcexceeding 500 GHz and power handling in the tens of watts are projected with optimization.