Photocurrent Characteristics of Gate/Body-Tied MOSFET-Type Photodetector with High Sensitivity

In this paper, the photocurrent characteristics of gate/body-tied (GBT) metal-oxide semiconductor field-effect transistor (MOSFET)-type photodetector with high sensitivity in the 408 nm - 941 nm range are presented. High sensitivity is important for photodetectors, which are used in several scientific and industrial applications. Owing to its inherent amplifying characteristics, the GBT MOSFET-type photodetector exhibits high sensitivity. The presented GBT MOSFET-type photodetector was designed and fabricated via a standard 0.18 μm complementary metal-oxide-semiconductor (CMOS) process, and its characteristics were analyzed. The photodetector was analyzed with respect to its width to length (W/L) ratio, bias voltage, and incident-light wavelength. It was confirmed experimentally that the presented GBT MOSFET-type photodetector has over 100 times higher sensitivity than a PN-junction photodiode with the same area in the 408 nm - 941 nm range.