P‐7: Improvement of PBTS Stability in Self‐Aligned Coplanar a‐IGZO TFTs

Abstract

We improve the PBTS instability of top‐gate coplanar amorphous InGaZnO TFTs by optimizing the buffer and gate insulator layers. The interface trap density is obtained from photonic capacitance‐voltage measurements and correlated with PBTS characteristics. Inter‐diffusion at the gate insulator interface lessens electron trap defects, which brings improvement in PBTS from ΔVth = 4.2 V to 0.5 V.