Backward Diode Rectifying Behavior in AgCrO2/In2O3

A backward diode consisting of all nondegenerate and transparent semiconducting oxides (TSOs) offers promising opportunities for designing multifunctional electronic devices. In this letter, we report the backward diode rectifying behavior in the nondegenerate AgCrO ₂ /In ₂ O ₃ p-n heterojunction. Both AgCrO ₂ and In ₂ O ₃ films are transparent. The decrease of grain boundary in the In ₂ O ₃ film can improve the backward diode rectifying performance. The optimized AgCrO ₂ /In ₂ O ₃ heterojunction exhibits a very high reverse rectification ratio that exceeds 10 ³ along with a small tunneling current onset voltage. The backward diode rectifying behavior originates from the electron band-to-band tunneling (BTBT) current in the reverse voltage region, which is induced by type-III band alignment. This study will pave the way for achieving transparent backward diodes by using all nondegenerate TSOs p-n heterojunctions.