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 ( $f_{\mathrm{ ug}}$ ) of 2.37 MHz, gain-bandwidth product (GBWP) of 7500 kHz, a slew rate (up/down) of (2.1/1.2) V/ $\mu \text{s}$ , and a phase margin (PM) of 102° at a supply voltage of ±10 V, the fabricated DG TFT op-amp demonstrates good performance among all a-IGZO-based literature.