Photodoping-driven crossover in low-frequency noise in MoS2 transistors

Abstract

Transition metal dichalcogenide field-effect transistors (FETs) have been actively explored for low-power electronics, light detection, and sensing. Albeit promising, their performance is strongly limited by low-frequency noise (LFN). Here, we report on the study of LFN in MoS${}_2$ FETs on SiO${}_2$ substrates in ambient conditions using photodoping. Using this external excitation source allows us to access different non-equilibrium steady states and cross over different noise regimes. We observe a dependence of the noise power spectrum with the transient decay time window, approaching $1/f$-type when the system is closer to equilibrium, and identify a dependence of the LFN with channel thickness. Monolayer/bilayer devices exhibit random telegraph noise for insulating regimes and $1/f$-type Hooge mobility fluctuations (HMF) for conductive regimes. Thicker devices exhibit mainly $1/f$-type carrier number fluctuations (CNF). In the latter, we observe a photodoping-induced change from a near parabolic to a near linear dependence of the inverse $1/f$ noise amplitude above the threshold gate voltage. This change indicates a crossover in the LFN mechanism from CNF to HMF. We demonstrate that the study of conductance and noise under photodoping is an effective tool to identify dominating carrier noise mechanisms in few-atomic-layer FETs for a wide range of doping regimes.

arXiv comment8 pages, 5 figures

References in corpus (12)

• Integrated Circuits Based on Bilayer MoS2 Transistors
• Photovoltaic effect in an electrically tunable van der Waals heterojunction
• Photocurrent generation with two-dimensional van der Waals semiconductors
• Review of the Low-Frequency 1/f Noise in Graphene Devices
• Ultrafast Dynamics of Defect-Assisted Electron-Hole Recombination in Monolayer MoS2
• Electron-hole transport and photovoltaic effect in gated MoS2 Schottky junctions
• Low Frequency Electronic Noise in Single-Layer MoS2 Transistors
• Surface Recombination Limited Lifetimes of Photoexcited Carriers in Few-Layer Transition Metal Dichalcogenide MoS2
• Low-Frequency 1/f Noise in Molybdenum Disulfide Transistors
• Pronounced photovoltaic response from multi-layered transition-metal dichalcogenides PN-junctions
• Low-Frequency 1/f Noise in MoS2 Thin-Film Transistors: Comparison of Single and Multilayer Structures
• Percolative switching in transition metal dichalcogenide field-effect transistors at room temperature

Cited by in corpus (2)

• Laser Annealing for Radiatively Broadened MoSe2 grown by Chemical Vapor Deposition
• Local photodoping in monolayer MoS2