High Performance Core-shell Junction Field Effect Phototransistor by Molecular Monolayer Doping

The state-of-art complementary metal-oxide-semiconductor (CMOS) technology requires highly sensitive photodetectors that are monolithically integrated. In this work, we demonstrate a high-performance core-shell junction field effect (JFET) phototransistors based on single silicon nanowires. The JFEF phototransistor is formed by doping a section of a highly doped p-type Si nanowire into n-type via self-assembled molecular monolayer doping. The p-type nanowire channel is pinched-off by the sectional doping, which suppresses the dark current and induces a large photogain. Experimental and simulation results show that the nanowire JFET photo-transistors possess a photoresponsivity of 10
⁶
A/W.