title: High-Speed Scalable Silicon-MoS2P-N Heterojunction Photodetectors.
abstract: Two-dimensional molybdenum disulfide (MoS2) is a promising material for ultrasensitive photodetector owing to its favourable band gap and high absorption coefficient. However, their commercial applications are limited by the lack of high quality p-n junction and large wafer scale fabrication process. A high speed Si/MoS2p-n heterojunction photodetector with simple and CMOS compatible approach has been reported here. The large area MoS2thin film on silicon platform has been synthesized by sulfurization of RF-sputtered MoO3films. The fabricated molecular layers of MoS2on silicon offers high responsivity up to 8.75 A/W (at 580 nm and 3 V bias) with ultra-fast response of 10 μsec (rise time). Transient measurements of Si/MoS2heterojunction under the modulated light reveal that the devices can function up to 50 kHz. The Si/MoS2heterojunction is found to be sensitive to broadband wavelengths ranging from visible to near-infrared light with maximum detectivity up to ≈1.4 × 1012Jones (2 V bias). Reproducible low dark current and high responsivity from over 20 devices in the same wafer has been measured. Additionally, the MoS2/Si photodetectors exhibit excellent stability in ambient atmosphere.
authors.affiliation: Centre for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi-110016, India.
authors.forename: Veerendra
authors.initials: V
authors.lastname: Dhyani
authors.affiliation: Centre for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi-110016, India.
authors.forename: Samaresh
authors.initials: S
authors.lastname: Das