Ultrahigh Responsivity and Tunable Photogain BEOL Compatible MoS2 Phototransistor Array for Monolithic 3D Image Sensor with Block-Level Sensing Circuits

A large-area and scalable monolayer TMD is feasible to employ in monolithic 3D image sensor scheme. For the first time, we represents a prototype MoS2 phototransistor array with ultrahigh responsivity (>103 A/W) and tunable photogain (102∼105) which can be directly implemented on a CMOS circuit connected with BEOL fine-pitch vertical interconnects. Electric gate pulse modulation mitigates photogating (PG) and persistent photoconductance (PPC) effects from layered semiconductor interface. Both three-order-of-magnitude improvements of response speed and fine-pitch vertical interconnects empower block-level compressive sensing circuits and global image-signal processing for gain control and data compression.