title: Highly sensitive wide bandwidth photodetector based on internal photoemission in CVD grown p-type MoS2/graphene Schottky junction.
abstract: Two dimensional (2D) Molybdenum disulfide (MoS2) has evolved as a promising material for next generation optoelectronic devices owing to its unique electrical and optical properties, such as band gap modulation, high optical absorption, and increased luminescence quantum yield. The 2D MoS2 photodetectors reported in the literature have presented low responsivity compared to silicon based photodetectors. In this study, we assembled atomically thin p-type MoS2 with graphene to form a MoS2/graphene Schottky photodetector where photo generated holes travel from graphene to MoS2 over the Schottky barrier under illumination. We found that the p-type MoS2 forms a Schottky junction with graphene with a barrier height of 139 meV, which results in high photocurrent and wide spectral range of detection with wavelength selectivity. The fabricated photodetector showed excellent photosensitivity with a maximum photo responsivity of 1.26 AW(-1) and a noise equivalent power of 7.8 × 10(-12) W/√Hz at 1440 nm.
authors.affiliation: †INSYST Laboratory, Electrical and Computer Engineering, Florida International University, Miami, Florida 33174, United States.
authors.forename: PhaniKiran
authors.initials: P
authors.lastname: Vabbina
authors.affiliation: ‡Nanomaterials and Device Laboratory, Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76207, United States.
authors.forename: Nitin
authors.initials: N
authors.lastname: Choudhary
authors.affiliation: †INSYST Laboratory, Electrical and Computer Engineering, Florida International University, Miami, Florida 33174, United States.
authors.forename: Al-Amin
authors.initials: AA
authors.lastname: Chowdhury
authors.affiliation: †INSYST Laboratory, Electrical and Computer Engineering, Florida International University, Miami, Florida 33174, United States.
authors.forename: Raju
authors.initials: R
authors.lastname: Sinha
authors.affiliation: †INSYST Laboratory, Electrical and Computer Engineering, Florida International University, Miami, Florida 33174, United States.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Karabiyik
authors.affiliation: ‡Nanomaterials and Device Laboratory, Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76207, United States.
authors.forename: Santanu
authors.initials: S
authors.lastname: Das
authors.affiliation: ‡Nanomaterials and Device Laboratory, Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76207, United States.
authors.forename: Wonbong
authors.initials: W
authors.lastname: Choi
authors.affiliation: †INSYST Laboratory, Electrical and Computer Engineering, Florida International University, Miami, Florida 33174, United States.
authors.forename: Nezih
authors.initials: N
authors.lastname: Pala
keywords: 2D hybrid materials; CVD; Schottky junction; atomic layer MoS2; graphene; photodetector