Competing weak localization and weak antilocalization in amorphous indium–gallium–zinc-oxide thin-film transistors

We have investigated the gate-voltage dependence and the temperature dependence of the magnetoconductivity of amorphous indium–gallium–zinc-oxide thin-film transistors. A weak-localization feature is observed at small magnetic fields on top of an overall negative magnetoconductivity at higher fields. An intriguing controllable competition between weak localization and weak antilocalization is observed by tuning the gate voltage or by varying the temperature. Our findings reflect controllable quantum interference competition in the electron systems in amorphous indium–gallium–zinc-oxide thin-film transistors.