Gate-Controlled MoS₂ Photodiode With Spectral Response From 450 to 1550 nm by Phosphorus-Implantation

Efficient p-type doping is at the top of the priority list for developing MoS2 electronics and optoelectronics devices due to MoS2 exhibiting the characteristics of an n-type semiconductor. However, implantation, a CMOS-compatible, controllable, and area-selective p-type doping process, is still unclear on MoS2. Here, it is reported that the phosphorus-implantation (P-implantation), a part of the CMOS process, can achieve p-type doping and extend cutoff wavelength from ~980 nm to a value over 1550 nm selectively by modulating implantation dose. By tuning the implantation dose, it was able to transform MoS2 from semiconductor to semimetal. Besides, we fabricate a gate-controlled MoS2 photodiode with spectral response from 450 to 1550 nm by P-implantation. The photodiode has 24 times more responsivity and 500 times the special detectivity than pristine transistor and achieves the responsivity of 6.1 A/W at 1550-nm illumination. In summary, this study opens a guideline for commercialization of MoS2 chips and enriches the application scenarios of MoS2 in NIR photodetection.