Widening the Wavelength Absorption Range of Indium Gallium Zinc Oxide Phototransistors through the Capping layer

Abstract

We propose indium gallium zinc oxide (IGZO) phototransistors with an extended wavelength detection range by a capping layer composed of hafnium oxide (HfO2). A HfO2 capping layer enables the generation of oxygen vacancies by strongly attracting oxygen ions in the back channel of IGZO. IGZO phototransistors with the capping layer exhibit improved optoelectronic characteristics, such as photoresponsivity of149.48 A/W, photosensitivity of 1.17 x 106, detectivity of 3.64 x 1010 Jones under the green light (532 nm) illumination of 10 m W/mm2. ? 2022 SID.