Photoelectric performance of InSe vdW semi-floating gate p–n junction transistor

Abstract

Semi-floating gate transistors based on vdW materials are often used in memory and programmable logic applications. In this paper, we propose a semi-floating gate photoelectric p–n junction transistor structure which is stacked by InSe/h-BN/Gr. By modulating gate voltage, InSe can be presented as N-type and P-type respectively on different substrates, and then combined into p–n junction. Moreover, InSe/h-BN/Gr device can be switched freely between N-type resistance and p–n junction. The resistance value of InSe resistor and the photoelectric properties of the p–n junction are also sensitively modulated by laser. Under dark conditions, the rectification ratio of p–n junction can be as high as 107. After laser modulation, the device has a response up to 1.154 × 104 A W−1, a detection rate up to 5.238 × 1012 Jones, an external quantum efficiency of 5.435 × 106%, and a noise equivalent power as low as 1.262 × 10−16 W/Hz1/2. It lays a foundation for the development of high sensitivity and fast response rate tunable photoelectric p–n junction transistor.