Universal dependence on the channel conductivity of the competing weak localization and antilocalization in amorphous InGaZnO₄ thin-film transistors

We investigate the gate-voltage dependence of the magnetoconductivity of several amorphous InGaZnO$_4$ (a-IGZO) thin-film transistors (TFTs). The magnetoconductivity exhibits gate-voltage- controlled competitions between weak localization (WL) and weak antilocalization (WAL), and the respective weights of WL and WAL contributions demonstrate an intriguing universal dependence on the channel conductivity regardless of the difference in the electrical characteristics of the a-IGZO TFTs. Our findings help build a theoretical interpretation of the competing WL and WAL observed in the electron systems in a-IGZO TFTs.