Gate-driven vertical and lateral self-powered behaviors in 213-nm GeO ₂ heterojunction solar-blind photodetectors

GeO 2 /SiO 2 /n-Si vertical heterojunctions have been designed for developing three-terminal self-powered solar-blind photodetectors (SBPDs). The gate-voltage-reduced channel resistance significantly enhances 213-nm photoresponse characteristics including a 1630-fold increase in photocurrent and 400 times in photo-to-dark current ratio for GeO 2 SBPDs. The coexistence of vertical and lateral self-powered behaviors with maximal ON/OFF ratios of 18 and 180 has been demonstrated due to the interfacial energy band alignment and the gate-driven vertical electric field, with which a proof-of-concept demonstration is further performed for four types of optoelectronic logic gates. Our findings provide a promising strategy and novel insights to develop GeO 2 -based SBPDs.