2D Dual Gate Field-Effect Transistor Enabled Versatile Functions

Advanced computing technologies such as distributed computing and the Internet of Things require highly integrated and multifunctional electronic devices. Beyond the Si technology, 2D-materials-based dual-gate transistors are expected to meet these demands due to the ultra-thin body and the dangling-bond-free surface. In this work, a molybdenum disulfide (MoS₂ ) asymmetric-dual-gate field-effect transistor (ADGFET) with an In₂ Se₃ top gate and a global bottom gate is designed. The independently controlled double gates enable the device to achieve an on/off ratio of 10⁶ with a low subthreshold swing of 94.3 mV dec^-1 while presenting a logic function. The coupling effect between the double gates allows the top gate to work as a charge-trapping layer, realizing nonvolatile memory (10⁵ on/off ratio with retention time over 10⁴ s) and six-level memory states. Additionally, ADGFET displays a tunable photodetection with the responsivity reaching the highest value of 857 A W^-1 , benefiting from the interface coupling between the double gates. Meanwhile, the photo-memory property of ADGFET is also verified by using the varying exposure dosages-dependent illumination. The multifunctional applications demonstrate that the ADGFET provides an alternative way to integrate logic, memory, and sensing into one device architecture.