MoS2 FETs Research Articles

Strain insensitive flexible photodetector based on molybdenum ditelluride/molybdenum disulfide heterostructure

Flexible electronic and optoelectronic devices are highly desirable for various emerging applications, such as human-computer interfaces, wearable medical electronics, flexible display, etc. Layered two-dimensional (2D) material is one of the most promising types of materials to develop flexible devices due to its atomically thin thickness, which gives it excellent flexibility and mechanical endurance. However, the 2D material devices fabricated on flexible substrate inevitably suffer from mechanical deformation, which can severely affect device performances, resulting in function degradation and even failure. In this work, we propose a strain insensitive flexible photodetector based on MoS2/MoTe2 heterostructure on polyimide substrate, which provides a feasible approach to cancel unpredicted impacts of strain on the device performances. Specifically, the MoS2/MoTe2 heterostructure is deposited with 4 electrodes to form three independent devices of MoS2 FET, MoTe2 FET and MoS2/MoTe2 heterojunction. Among them, the MoS2/MoTe2 heterojunction is used as the photodetector, while the MoS2 FET is used as a strain gauge to calibrate the photo detection result. Such configuration is enabled by the Schottky barrier formed between the electrodes and the MoS2 flake, which leads to obvious and negligible photo response of MoS2/MoTe2 heterojunction and MoS2 FET, respectively, under low source-drain bias (ex. 10 mV). The experimental results show that the proposed mechanism can not only calibrate the photo response to cancel strain effect, but also successfully differentiate the wavelength (with fixed power) or power (with fixed wavelength) of light illumination.

Design for performance improvement via structure optimization and contact engineering in MoS2 FETs with 2 nm gate length

To provide theoretical designs for performance improvement, MoS2-based FETs with 2 nm gate length are investigated by numerical simulations. It is found that by optimizing structure with underlap (UL), off-current (I off) is suppressed by ∼103 in MoS2 FETs. Contact engineering by H-passivation could modulate the Schottky barrier for higher on-current (I on) and lower subthreshold swing in Si-MoS2 FETs. More importantly, even in Si-MoS2 FETs with 2 nm gate length, ∼107 I on/I off could be achieved by structure optimization to suppress I off and contact engineering to modulate the Schottky barrier. Our results are significant to guide designs of MoS2 integrations in ultimate-scaled technology.

Effects of Channel Length Scaling on the Electrical Characteristics of Multilayer MoS2 Field Effect Transistor

With the rapid miniaturization of integrated chips in recent decades, aggressive geometric scaling of transistor dimensions to nanometric scales has become imperative. Recent works have reported the usefulness of 2D transition metal dichalcogenides (TMDs) like MoS2 in MOSFET fabrication due to their enhanced active surface area, thin body, and non-zero bandgap. However, a systematic study on the effects of geometric scaling down to sub-10-nm nodes on the performance of MoS2 MOSFETs is lacking. Here, the authors present an extensive study on the performance of MoS2 FETs when geometrically scaled down to the sub-10 nm range. Transport properties are modelled using drift-diffusion equations in the classical regime and self-consistent Schrödinger-Poisson solution using NEGF formulation in the quantum regime. By employing the device modeling tool COMSOL for the classical regime, drain current vs. gate voltage (ID vs. VGS) plots were simulated. On the other hand, NEGF formulation for quantum regions is performed using MATLAB, and transfer characteristics are obtained. The effects of scaling device dimensions, such as channel length and contact length, are evaluated based on transfer characteristics by computing performance metrics like drain-induced barrier lowering (DIBL), on-off currents, subthreshold swing, and threshold voltage.

Real time estimation of stem cell zeta potential and dimension during proliferation using MoS2 nanosheets field effect transistor

In this paper, we demonstrate a unique FET system composed of vertically aligned MoS2nanosheets for real time, label free monitoring of zeta potential and dimension of mesenchymal stem cells during proliferation. To avoid the interference from non-specifically adsorbed macromolecules, a time varying electric field with an optimized frequency of 10 kHz has been applied at the gate and effective gate bias has been estimated from the real time drain current measurement in an electrical double layer gated cell-coupled FET platform. Special signal patterns corresponding to the alterations in the cell membrane potential have been observed. Extraction of cell parameters from the experimental observations, using closed set of equations reveal that the results correlate well with the gold standards and a high transconductance has enabled tracking of cell count with sufficient accuracy. The MoS2 FET signal has been compared with the pH change of the cell culture medium and the signal follows the cell proliferation related activity more closely than the pH change. Thus, it may be expected that this platform can substitute the existing time consuming and laborious methods.

A steep-switching impact ionization-based threshold switching field-effect transistor.

A steep switching device with a low subthreshold swing (SS) that overcomes the fundamental Boltzmann limit (kT/q) is required to efficiently process a continuously increasing amount of data. Recently, two-dimensional material-based impact ionization transistors with various structures have been reported with the advantages of a low critical electric field and a unique quantum confinement effect. However, most of them cannot retain steep switching at room temperature, and device performance degradation issues caused by impact ionization-induced hot carriers have not been structurally addressed. In this study, we presented an impact-ionization-based threshold switching field-effect transistor (I2S-FET) fabricated with a serial connection of a MoS2 FET and WSe2 impact ionization-based threshold switch (I2S). We obtained repetitive operation with low SS (32.8 mV dec-1) at room temperature, along with low dielectric injection efficiency (10-6), through a structural design with separation of the conducting region, which determines on-state carrier transport, and the steep-switching region where the transition from off- to on-state occurs via impact ionization. Furthermore, compared to previously reported threshold-switching devices, our device demonstrated hysteresis-free switching characteristics. This study provides a promising approach for developing next-generation energy-efficient electronic devices and ultralow-power applications.

Quasi-Volatile MoS2 Barristor Memory for 1T Compact Neuron by Correlative Charges Trapping and Schottky Barrier Modulation.

Artificial neurons as the basic units of spiking neural network (SNN) have attracted increasing interest in energy-efficient neuromorphic computing. 2D transition metal dichalcogenide (TMD)-based devices have great potential for high-performance and low-power artificial neural devices, owing to their unique ion motion, interface engineering, and resistive switching behaviors. Although there are widespread applications of TMD-based artificial synapses in neural networks, TMD-based neurons are seldom reported due to the lack of bio-plausible multi-mechanisms to mimic leaking, integrating, and firing biological behaviors without external assistance. In this work, for the first time, a methodology is developed by introducing the hybrid effect of charge trapping (CT) and Schottky barrier (SB) in MoS2 FETs for barristor memory and one-transistor (1T) compact artificial neuron realization. By correlating the CT and SB processes, quasi-volatile and resistive switching behaviors are realized on the fabricated MoS2 FET and utilized to mimic the accumulating, leaking, and firing biological behaviors of neurons. Therefore, based on a single quasi-volatile CT-SB MoS2 barristor memory, a 1T compact neuron of the basic leaky-integral-and-fire (LIF) function is demonstrated without a peripheral circuit. Furthermore, a spiking neural network (SNN) based on the CT-SB MoS2 barristor neurons is simulated and implemented in pattern classification with high accuracy approaching 95.82%. This work provides a highly integrated and inherently low-energy implementation for neural networks.

A steep switching WSe2 impact ionization field-effect transistor

The Fermi-Dirac distribution of carriers and the drift-diffusion mode of transport represent two fundamental barriers towards the reduction of the subthreshold slope (SS) and the optimization of the energy consumption of field-effect transistors. In this study, we report the realization of steep-slope impact ionization field-effect transistors (I2FETs) based on a gate-controlled homogeneous WSe2 lateral junction. The devices showed average SS down to 2.73 mV/dec over three decades of source-drain current and an on/off ratio of ~106 at room temperature and low bias voltages (<1 V). We determined that the lucky-drift mechanism of carriers is valid in WSe2, allowing our I2FETs to have high impact ionization coefficients and low SS at room temperature. Moreover, we fabricated a logic inverter based on a WSe2 I2FET and a MoS2 FET, exhibiting an inverter gain of 73 and almost ideal noise margin for high- and low-logic states. Our results provide a promising approach for developing functional devices as front runners for energy-efficient electronic device technology.

Transfer-free, scalable vertical heterostructure FET on MoS2/WS2 continuous films

Taking into account the novel layered structure and unusual electronic properties of MoS2 and WS2 on the side the lack of dangling bonds between these two components and donor–acceptor linkage effects, growth of the MoS2/WS2 vertical heterojunction film on the amorphous SiO2/Si substrate have created high demand. In this study, we reported the continuous, scalable, and vertical MoS2/WS2 heterostructure film by using a sputtering without a transfer step. The WS2 film was continuously grown on MoS2 and eventually led to the formation of the MoS2/WS2 vertical heterojunction film. Dozens of FETs fabricated on MoS2/WS2 continuous heterojunction film were created on the same substrate in a single lithographic fabrication step, allowing them to be commercialized and not only used in research applications. RAMAN spectra proved the formation of the MoS2/WS2 heterostructure film. In XPS measurements, it was shown that a separate MoS2 and WS2 layer was grown instead of the alloy structure. The polarity behavior of the MoS2/WS2 heterostructure FET was found to be modulated with different drain voltages as p-type to ambipolar and finally n-type conductivity because of the transition of band structure and Schottky barrier heights at different drain voltages. Electron mobility (7.2 cm2 V.s−1) and on/off ratio (104–105) exhibited by the MoS2/WS2 heterostructure FETs displayed a more improved electrical performance than that of individual WS2, MoS2 devices. It was observed that the mobility value of MoS2/WS2 FET was approximately 514 times greater than WS2 FET and 800 times greater than MoS2 FET. Additionally, the MoS2/WS2 FET on/off ratio was larger than 2 order MoS2 FET and 1 order WS2 FET. The film of continuous vertical heterojunctions as in the MoS2/WS2 currents in the study would be a promising candidate for nanoelectronics fields. This work demonstrated the progress towards realizing carrier-type controlled high-performance MoS2/WS2 heterojunction-based FETs for future logic devices.

Analytical modeling of dielectric modulated negative capacitance MoS2 field effect transistor for next‐generation label‐free biosensor

AbstractIn this paper, a dielectric modulated negative capacitance (NC) MoS2 FET‐based biosensor is proposed for label‐free detection of biomolecules such as enzymes, proteins, DNA, and so forth. Various reports present on experimental demonstration and modeling of NC MoS2 FET but it is never utilized as a dielectric modulated biosensor. So, in this work, the modeling, characterization and sensitivity analysis of dielectric modulated NC MoS2 FET is focused. For immobilization of biomolecules, a nanocavity is formed below the gate by etching some portion of the gate oxide material. The immobilization of biomolecules in the cavity leads to a variation of different electrostatic properties such as surface potential, threshold voltage, drain current, and subthreshold swing which can be utilized as sensing parameters. An analytical model for the proposed biosensor is also developed in the subthreshold region by considering the properties of two‐dimensional ferroelectric materials and benchmarked with TCAD device simulations. The effect of change of gate length and doping concentration on different electrical properties is also analyzed to estimate the optimum value of channel doping. The results prove that the proposed device can be used for next‐generation low power label‐free biosensor which shows enhanced sensitivity as compared to traditional FET‐based biosensors.

Large-Scale Ultrafast Strain Engineering of CVD-Grown Two-Dimensional Materials on Strain Self-Limited Deformable Nanostructures toward Enhanced Field-Effect Transistors.

Strain engineering of 2D materials is capable of tuning the electrical and optical properties of the materials without introducing additional atoms. Here, a method for large-scale ultrafast strain engineering of CVD-grown 2D materials is proposed. Locally nonuniform strains are introduced through the cooperative deformation of materials and metal@metal oxide nanoparticles through cold laser shock. The tensile strain of MoS2 changes and the band gap decreases after laser shock. The mechanism of the ultrafast straining is investigated by MD simulations. MoS2 FETs were fabricated, and the field-effect mobility of devices could be increased from 1.9 to 44.5 cm2 V-1 s-1 by adjusting the strain level of MoS2. This is currently the maximum value of MoS2 FETs grown by CVD with SiO2 as the dielectric. As a large-scale and ultrafast manufacturing method, laser shock provides a universal strategy for large-scale adjustment of 2D material strain, which will help to promote the manufacturing of 2D nanoelectronic devices.

A facile approach towards Wrinkle-Free transfer of 2D-MoS2 films via hydrophilic Si3N4 substrate

Two-dimensional (2D) transition-metal dichalcogenides (TMDs) have been widely explored as next-generation semiconductor materials owing to their attractive electrical and optical properties. Currently, high-performance 2D-TMD-based electronic devices are obtained by transferring growth substrates onto target substrates. In practice, however, transfer-induced wrinkles and structural deformation on the target substrate pose a significant challenge. Herein, we successfully demonstrated a wrinkle-free transfer method that could facilely control the wrinkles of MoS2 thin films on hydrophilic Si3N4 substrates. Owing to the high wettability of the Si3N4 substrate, the residual water droplets between the MoS2 thin film and the target substrate were effectively removed, minimizing unexpected wrinkles and structural deformation. By simply adjusting the wetting properties of the target substrate, the device performance improved to a field-effect mobility of ∼ 0.756 cm2/(V·s), which is six times higher than that of the SiO2 substrate. Furthermore, the standard deviation of the electrical characteristics of the 50 2D-field-effect transistors was reduced by the Si3N4 substrate. In addition, the intrinsic characteristics of the MoS2 FET were evaluated by suppressing the effect of charge trapping through pulsed I-V measurements. Facilely-controlled wrinkles in MoS2 thin films can be used in various electronic devices, sensors, optoelectronic devices, and neuromorphic devices.

On‐Chip Integrated High Gain Complementary MoS2 Inverter Circuit with Exceptional High Hole Current P‐Channel Field‐Effect Transistors

AbstractIntegration of complementary logic circuits using 2D layered MoS2 can overcome the fundamental device limitations of silicon‐based Complementary metal–oxide–semiconductor (CMOS) technology. For the high functionality of complementary MoS2 logic circuits, realizing high‐current p‐channel MoS2 field‐effect transistors (p‐FETs) is essential yet quite challenging. Herein, passivation of surface defects of MoS2 by atomic oxygen is proposed theoretically by ab initio simulations in favor of mitigating the Fermi level pinning. Experimentally, an atomic layer passivation (ALP) technique combined with a slow metal‐deposition strategy is developed to reduce contact resistance to p‐channel MoS2 and report a more than tenfold increase in the contact hole conductance. The fabricated p‐channel MoS2 FETs achieve a record high saturation current of 45 µA µm−1 with a 0.7 µm channel length under a VDS of −1 V. With these techniques, an electron–hole pairing in MoS2 similar to the Si counterpart is achieved for complementary circuit applications. An on‐chip integrated MoS2 inverter with Pt electrodes is demonstrated with a high gain of 20 at 3 V supply.

Multiwavelength Optoelectronic Synapse with 2D Materials for Mixed-Color Pattern Recognition.

Neuromorphic visual systems emulating biological retina functionalities have enormous potential for in-sensor computing, with prospects of making artificial intelligence ubiquitous. Conventionally, visual information is captured by an image sensor, stored by memory units, and eventually processed by the machine learning algorithm. Here, we present an optoelectronic synapse device with multifunctional integration of all the processes required for real time object identification. Ultraviolet-visible wavelength-sensitive MoS2 FET channel with infrared sensitive PtTe2/Si gate electrode enables the device to sense, store, and process optical data for a wide range of the electromagnetic spectrum, while maintaining a low dark current. The device exhibits optical stimulation-controlled short-term and long-term potentiation, electrically driven long-term depression, synaptic weight update for multiple wavelengths of light ranging from 300 nm in ultraviolet to 2 μm in infrared. An artificial neural network developed using the extracted weight update parameters of the device can be trained to identify both single wavelength and mixed wavelength patterns. This work demonstrates a device that could potentially be used for realizing a multiwavelength neuromorphic visual system for pattern recognition and object identification.

Wafer-Scale Demonstration of MBC-FET and C-FET Arrays Based on Two-Dimensional Semiconductors.

Two-dimentional semiconductors have shown potential applications in multi-bridge channel field-effect transistors (MBC-FETs) and complementary field-effect transistors (C-FETs) due to their atomic thickness, stackability, and excellent electrical properties. However, the exploration of MBC-FET and C-FET based on large-scale 2D semiconductors is still lacking. Here, based on a reliable vertical stacking of wafer-scale 2D semiconductors, large-scale MBC-FETs and C-FETs using n-type MoS2 and p-type MoTe2 are successfully fabricated. The drive current of an MBC-FET with two layers of MoS2 channel (20µm/10µm) is up to 60µA under 1V bias. Compared with the single-gate MoS2 FET, the carrier mobility of MBC-FET is 2.3 times higher and the sub-threshold swing is 70% smaller. Furthermore, NAND and NOR logic circuits are also constructed based on two vertically stacked MoS2 channels. Then, C-FET arrays are fabricated by 3D integrating n-type MoS2 FET and p-type MoTe2 FET, which exhibit a voltage gain of 7V/V when VDD = 4V. In addition, this C-FET device can directly convert light signals to an electrical digital signal within a single device. The demonstration of MBC-FET and C-FET based on large-scale 2D semiconductors will promote the application of 2D semiconductors in next-generation circuits.

Tailoring the Electrical Characteristics of MoS2 FETs through Controllable Surface Charge Transfer Doping Using Selective Inkjet Printing.

Surface charge transfer doping (SCTD) has been regarded as an effective approach to tailor the electrical characteristics of atomically thin transition metal dichalcogenides (TMDs) in a nondestructive manner due to their two-dimensional nature. However, the difficulty of achieving rationally controlled SCTD on TMDs via conventional doping methods, such as solution immersion and dopant vaporization, has impeded the realization of practical optoelectronic and electronic devices. Here, we demonstrate controllable SCTD of molybdenum disulfide (MoS2) field-effect transistors using inkjet-printed benzyl viologen (BV) as an n-type dopant. By adjusting the BV concentration and the areal coverage of inkjet-printed BV dopants, controllable SCTD results in BV-doped MoS2 FETs with elaborately tailored electrical performance. Specifically, the suggested solvent system creates well-defined droplets of BV ink having a volume of ∼2 pL, which allows the high spatial selectivity of SCTD onto the MoS2 channels by depositing the BV dopant on demand. Our inkjet-printed SCTD method provides a feasible solution for achieving controllable doping to modulate the electrical and optical performances of TMD-based devices.

Improved Performance of MoS2 FETs using AlN/Al2 O3 dielectric and Plasma Enhanced Atomic Layer Deposition (PEALD)

Molybdenum disulfide (MoS2 ) transistors are emerging as an exciting material system for future electronics due to their unique electrical properties, twodimensional (2D) nature and atomically thin geometry. This ultra-thin-body (UTB) semiconductor considerably reduces current leakage and enables gate-to-channel control. The homogeneous growth of sub-10 nm dielectrics on 2D materials remains challenging. We demonstrate high-performance MoS2 FETs at low temperature (150°C) using the plasma-enhanced Atomic layer deposition (PEALD) technique. The device exhibits a high on/off current ratio of about 106 , the field-effect mobility of 9.5 cm2 /Vs, and a subthreshold swing (SS) of 171 mV/dec, which is comparable to the similar structure of the top gate device. In addition, we have demonstrated contact resistance on back-gate MoS2 FETs with and without dielectric capping

Superior resistance switching in monolayer MoS2 channel-based gated binary resistive random-access memory via gate-bias dependence and a unique forming process

Resistance switching (RS) in 2D molybdenum disulfide (MoS2) was recently discovered. Since the discovery, many reports demonstrating MoS2 resistive random-access memory (RRAM) with synapse-like behavior have been published. These reports strongly justify applications of MoS2 RRAM in neuromorphic hardware as well as an alternative to conventional binary memories. In this work, we unveil the effect of RS, induced by current–voltage hysteresis cycles across CVD-grown monolayer MoS2-based gated RRAM, on its transistor’s electrical and reliability characteristics. A unique gate voltage dependence on the RS is identified which has a remarkable impact on the switching performance of MoS2 RRAM. RS behavior was found to be significantly dependent on the charge conduction in the channel. Moreover, we have shown a potential device-forming event when MoS2-gated RRAMs were subjected to a steady-state electrical stress. Both hysteresis and steady-state electrical stress were found to disturb the transistor action of these gated RRAMs, which can in fact be used as a signature of RS. Interestingly, current–voltage hysteresis resulted in unipolar RS, whereas steady-state electrical stress before RS measurement led to bipolar RS. Moreover, successive stress cycles of such electrical stress lead to multiple resistance states, a behavior similar to synaptic properties such as long-term potentiation and long-term depression, typically found in memristors. We find that the charge transport mechanism dominant in the MoS2 FET, in conjunction with steady-state stress-induced device forming, determine the extent of RS induced in thes MoS2-based gated RRAMs. Finally, on the basis of insights developed from the dependence on the charge transport mechanism and steady-state stress-induced forming of the MoS2 channel, we propose a certain steady-state electrical stress condition which can be used as a ‘forming’ process, employed prior to the use of MoS2-based binary RRAMs for improved switching performance.

Ultrafast and Highly Sensitive Dual-Channel FET Photodetector Based on a Two-Dimensional MoS2 Homojunction.

Two-dimensional transition metal dichalcogenide-based phototransistors have been intensively studied in recent years due to their high detection rate and flexibility. However, the photogating effect, usually appearing in the devices, leads to a poor transient photoresponse, which slows down the imaging rate of the camera based on the devices. Here, we demonstrate a dual-channel two-dimensional field-effect phototransistor composed of a vertical molybdenum disulfide (MoS2) p-n homojunction as the sensitizing channel layer. Owing to the effective separation by the vertical built-in electric field and rapid migration of photoexcited electrons and holes in the separated channels, the fabricated dual-channel FET device simultaneously exhibits prominent responsivity and greatly improved time response in comparison to the pristine MoS2 FET detectors. Excellent device performance has been achieved, with a responsivity of 3.4 × 104 A/W at a source-drain voltage (VDS) of 1 V, corresponding to a detectivity (D*) of 1.9 × 1013 Jones@532 nm and a gain of more than 105 electrons per photon, an external quantum efficiency of 9.6%, and a response time of tens of milliseconds. Especially, the response time of the dual-channel FET device is 3 orders of magnitude faster than that of the pristine device. Our results provide a new way to overcome the inherent photogating drawback of two-dimensional FET optoelectronic devices and to develop a related high frame rate imaging system.

(Invited) Optoelectronic Synapses with Two Dimensional Materials for Neuromorphic Computing

Optoelectronic synapses are devices that behave like photodetectors with analog memory. In neuromorphic computing, these devices have the potential to perform imaging and object identification using the same device. We first demonstrate that the strong photogeneration efficiency of methylammonium lead bromide perovskite quantum dots (PQDs) can be exploited by growing PQDs from the lattice of a single layer graphene by a defect-mediated process. The rationale for designing this hybrid superstructure stems from the ability of PQDs to absorb light and generate charge carriers. The charges generated are transferred to graphene, which transports the carriers across the active layer of the device. Through the implementation of this thin superstructure in a phototransistor geometry, we produce a photoresponsivity of 1.4×108 AW-1 at 430 nm and a specific detectivity (D*) of 4.72×1015 Jones, which is by far the best responsivity and detectivity across similar devices reported to date. This is promising for the development of highly efficient optoelectronic materials for high-speed communications, sensing, ultra-sensitive cameras and high-resolution imaging and displays. The graphene-PQD superstructure behaves as an optoelectronic synapse with low energy consumption of 36.75 pJ/ spike that mimics crucial characteristics of its biological equivalent, with unique optical potentiation and electrical habituation function. We also utilized the persistent photoconductivity of 2D MoS2 layers to demonstrate an optoelectronic synapse. A CVD-grown monolayer MoS2 FET exhibits substantial enhancement in drain current when illuminated with a laser of 450 nm wavelength as well as a negative shift in its threshold voltage due to the generation of photocarriers. The device undergoes optical potentiation and electrical depression. The device is “optically” potentiated by applying light pulses with ON/OFF interval of 5 s for each at 450 nm wavelength – measured at a constant drain bias of 1.0 V with VG = -2 V. Also, it is “electrically” depressed by applying 50 electrical pulses with ON/OFF interval of 1 s and 9 s, respectively – measured at a drain bias of -100 mV with VG = -2 V. These results confirm the active and simultaneous tunability of conductance essential for the electrical/optical training of optoelectronic synapse in neural network applications. The negative voltage pulses applied at the drain de-traps the holes from the SiO2/MoS2 interface, thus gradually depress the device to its initial low conductance state.

Modeling of a tunable memory device made with a double-gate MoS2 FET and graphene floating gate

Electronic devices comprising low-temperature processed 2D materials can be utilized in back-end-of-line nonvolatile memory and logic applications, to augment conventional silicon technology. A promising structure for a low-temperature processed digital nonvolatile flash memory device and/or logic device is the double-gate MoS2 FET with a graphene floating gate and a thin h-BN gate dielectric serving as a tunneling dielectric. In this work, we show that experimental hysteretic current–voltage characteristics of this digital flash memory device can be well fit by a simple and effective physics-based model using a WKB approximation to calculate the tunneling current to the graphene floating gate and a capacitive network with 2D density-of-states to calculate the channel current flowing in the MoS2 channel. Accordingly, the model allows a device designer to predict and/or tune characteristics for this memory device, e.g., the width and center-position of the hysteresis loop as well as the value of source–drain current, as a function of both the bottom (control) gate and top (FET) gate voltages. It is noted that shifting of the center-position of the hysteresis loop enables improved reliability and functionality of the memory device in circuit applications and is a unique feature of this double-gated MoS2 FET. Overall, the demonstrated ability to well model this memory device lends further credence that 2D devices could augment silicon technology.