A High Performance Operational Amplifier Using Coplanar Dual Gate a-IGZO TFTs

We fabricate an operational amplifier (op-amp) composed with the coplanar amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs). The circuit consisted of 19-TFTs and designed on a glass substrate in both dual gate (DG) and single gate (SG) structure for performance evaluation. Having the yield of a total voltage gain (A(v)) of 23.5 dB, a cutoff frequency (f(c)) of 500 kHz, a unit gain frequency (f(ug)) of 2.37 MHz, gain-bandwidth product (GBWP) of 7500 kHz, a slew rate (up/down) of (2.1/1.2) V/mu s, and a phase margin (PM) of 102 degrees at a supply voltage of +/- 10 V, the fabricated DG TFT op-amp demonstrates good performance among all a-IGZO-based literature.