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The development of silicon semiconductor technology has produced breakthroughs in electronics--from the microprocessor in the late 1960s to early 1970s, to automation, computers and smartphones--by downscaling the physical size of devices and wires to the nanometre regime. Now, graphene and related two-dimensional (2D) materials offer prospects of unprecedented advances in device performance at the atomic limit, and a synergistic combination of 2D materials with silicon chips promises a heterogeneous platform to deliver massively enhanced potential based on silicon technology. Integration is achieved via three-dimensional monolithic construction of multifunctional high-rise 2D silicon chips, enabling enhanced performance by exploiting the vertical direction and the functional diversification of the silicon platform for applications in opto-electronics and sensing. Here we review the opportunities, progress and challenges of integrating atomically thin materials with silicon-based nanosystems, and also consider the prospects for computational and non-computational applications. Progress in integrating atomically thin two-dimensional materials with silicon-based technology is reviewed, together with the associated opportunities and challenges, and a roadmap for future applications is presented., Author(s): Deji Akinwande [sup.1] , Cedric Huyghebaert [sup.2] , Ching-Hua Wang [sup.3] , Martha I. Serna [sup.1] , Stijn Goossens [sup.4] , Lain-Jong Li [sup.5] , H.-S. Philip Wong [sup.3] [...]

Monolayer molybdenum disulfide has been previously discovered to exhibit non-volatile resistive switching behavior in a vertical metal-insulator-metal structure, featuring ultra-thin sub-nanometer active layer thickness. However, the reliability of these nascent 2D-based memory devices was not previously investigated for practical applications. Here, we employ an electron irradiation treatment on monolayer MoS2 film to modify the defect properties. Raman, photoluminescence, and X-ray photoelectron spectroscopy measurements have been performed to confirm the increasing amount of sulfur vacancies introduced by the e-beam irradiation process. The statistical electrical studies reveal the reliability can be improved by up to 1.5× for yield and 11× for average DC cycling endurance in the devices with a moderate radiation dose compared to unirradiated devices. Based on our previously proposed virtual conductive-point model with the metal ion substitution into sulfur vacancy, Monte Carlo simulations have been performed to illustrate the irradiation effect on device reliability, elucidating a clustering failure mechanism. This work provides an approach by electron irradiation to enhance the reliability of 2D memory devices and inspires further research in defect engineering to precisely control the switching properties for a wide range of applications from memory computing to radio-frequency switches. [ABSTRACT FROM AUTHOR]

2D materials have been of considerable interest as new materials for device applications. Non‐volatile resistive switching applications of MoS2 and WS2 have been previously demonstrated; however, these applications are dramatically limited by high temperatures and extended times needed for the large‐area synthesis of 2D materials on crystalline substrates. The experimental results demonstrate a one‐step sulfurization method to synthesize MoS2 and WS2 at 550 °C in 15 min on sapphire wafers. Furthermore, a large area transfer of the synthesized thin films to SiO2/Si substrates is achieved. Following this, MoS2 and WS2 memristors are fabricated that exhibit stable non‐volatile switching and a satisfactory large on/off current ratio (103–105) with good uniformity. Tuning the sulfurization parameters (temperature and metal precursor thickness) is found to be a straightforward and effective strategy to improve the performance of the memristors. The demonstration of large‐scale MoS2 and WS2 memristors with a one‐step low‐temperature sulfurization method with simple strategy to tuning can lead to potential applications such as flexible memory and neuromorphic computing. [ABSTRACT FROM AUTHOR]

Abstract: Tin diselenide (SnSe2) has been recently investigated as an alternative layered metal dichalcogenide due to its unique electrical and optoelectronics properties. Although there are several reports on the deposition of layered crystalline SnSe2 films by chemical and physical methods, synthesis methods like pulsed laser deposition (PLD) are not reported. An attractive feature of PLD is that it can be used to grow 2D films over large areas. In this report, a deposition process to grow stoichiometric SnSe2 on different substrates such as single crystals (Sapphire) and amorphous oxides (SiO2 and HfO2) is reported. A detailed process flow for the growth of 2D SnSe2 at temperatures of 300 °C is presented, which is substantially lower than temperatures used in chemical vapor deposition and molecular beam epitaxy. The 2D SnSe2 films exhibit a mobility of ≈4.0 cm2 V−1 s−1, and are successfully used to demonstrate SnSe2/p‐Si heterojunction diodes. The diodes show I on/I off ratios of 103–104 with a turn on voltage of <0.5 V, and ideality factors of 1.2–1.4, depending on the SnSe2 film growth conditions. [ABSTRACT FROM AUTHOR]

Two-dimensional materials such as graphene and MoS2 have been the main focus of intense research efforts over the past few years. The most common method of exfoliating these materials, although efficient for lab-scale experiments, is not acceptable for large area and practical applications. Here, we report the deposition of MoS2 layered films on amorphous (SiO2) and crystalline substrates (sapphire) using a pulsed laser deposition (PLD) method. Increased substrate temperature (∼700 °C) and laser energy density (>530 mJ /cm2) promotes crystalline MoS2 films < 20 nm, as demonstrated by fast Fourier transform (FFT) and transmission electron microscopy (TEM). The method reported here opens the possibility for large area layered MoS2 films by using a laser ablation processes. [ABSTRACT FROM AUTHOR]