Engineering MoSe2/MoS2 heterojunction traps in 2D transistors for multilevel memory, multiscale display, and synaptic functions

Abstract

We study a low voltage short pulse operating multilevel memory based on van der Waals heterostack (HS) n-MoSe2/n-MoS2 channel field-effect transistors (FETs). Our HS memory FET exploited the gate voltage (VGS)-induced trapping/de-trapping phenomena for Program/Erase functioning, which was maintained for long retention times owing to the existence of heterojunction energy barrier between MoS2 and MoSe2. More interestingly, trapped electron density was incrementally modulated by the magnitude or cycles of a pulsed VGS, enabling the HS device to achieve multilevel long-term memory. For a practical demonstration, five different levels of drain current were visualized with multiscale light emissions after our memory FET was integrated into an organic light-emitting diode pixel circuit. In addition, our device was applied to a synapse-imitating neuromorphic memory in an artificial neural network. We regard our unique HS channel FET to be an interesting and promising electron device undertaking multifunctional operations related to the upcoming fourth industrial revolution era.

Insulator-to-metal phase transition in a few-layered MoSe2 field effect transistor

“…Our data demonstrate that the MoSe 2 device showed high electron doping, as previously reported by several research groups. [21][22][23][24] The electron-doped behavior in MoSe 2 is found to originate from the high density of Se vacancies in MoSe 2 , similar to the S-vacancy in MoS 2 crystals. 25,26 It is clear that at 5.7 K, higher V bg is required to turn the device ON, but it is also apparent that the slope of the current rise in the ON state has increased.…”

2D-Material-Based Volatile and Nonvolatile Memristive Devices for Neuromorphic Computing

“…On this basis, image recognition was successfully implemented based on the RC in the device. Jeong et al developed a 3T synaptic device based on 2D MoSe 2 /2D MoS 2 heterojunction . The n-MoSe 2 /n-MoS 2 structure was used as a channel of the device.…”

Dative bonding as a mechanism for enhanced catalysis on the surface of MoS2

“…Two-dimensional (2D) transition metal dichalcogenide (TMD) layers are among the most widely studied materials for potential applications in electronic devices [1][2][3][4][5][6][7][8]. The interest stems from the intrinsic properties of TMDs, which arise due to their characteristic structure.…”