Highly Efficient Filterless Bilateral Majority Carrier-Type Color Photodetectors

摘要

Photodetectors (PDs) are essential for promoting the modern technologyreliantlifestyles. Accordingly, the demand for efficient PDs with built-insignal amplification capabilities is constantly increasing. Generally, built-insignal amplification is achieved using an avalanching process that operatesat a high bias voltage with inevitable excess noise. In this study, back-tobackSchottky diodes (BTB SDs) are designed to demonstrate a significantamplification of signals at low bias voltages with relatively low excess noise.Furthermore, the detection efficiency is bilateral and relies less on the illuminatedjunction or the bias polarity, but is influenced by the wavelength ofthe illuminating light owing to the specific device structures employed. Thisenables the identification of the color of the incident light without using anycolor filters. The BTB graphene–insulator–silicon-on-insulator (BTB G–I–SOI)PDs fabricated with controlled interfacial oxides exhibit photoresponsivityup to 2.01 × 10~4 A W~(?1), specific detectivity of 1.57 × 10~(14) cm Hz~(1/2) W~(?1) at 5 V,and a rapid response (≈0.3 ms) for a two-millimeter-long channel. Thus, BTBG–I–SOI PDs are highly efficient filterless color sensors that establish a novelroute for diverse applications of PDs.