Two-dimensional reconfigurable electronics enabled by asymmetric floating gate
Tengyu Jin, Jing Gao, Yanan Wang, Yue Zheng, Shuo Sun, Lei Liu, Ming Lin, Wei Chen
Abstract
Reconfigurable devices with customized functionalities hold great potential in addressing the scaling limits of silicon-based field-effect transistors (FETs). The conventional reconfigurable FETs are limited to the applications in logic circuits, and the commonly used multi-gate programming strategies often lead to high power consumption and device complexity. Here, we report a reconfigurable WSe2 optoelectronic device that can function as photodiode, artificial synapse, and 2-bit memory in a single device, enabled by an asymmetric floating gate (AFG) that can continuously program the device into different homojunction modes. The lateral p–n homojunction formed in the AFG device exhibits high-performance self-powered photodetection, with a responsivity over 0.17 A·W−1 and a wide detection spectral range from violet to near-infrared region. The AFG device can also mimic synaptic features of biological synapses and achieve distinct potentiation/depression behaviors under the modulation of both drain-source bias and light illumination. Moreover, when working as a 2-bit memory via the transition between n–n+ and p–n homojunctions, the AFG device shows four distinct conductive states with a high on/off current ratio over 106 and good repeatability. Combining reduced processing complexity and reconfigurable functionalities, the WSe2 AFG devices demonstrate great potential towards high-performance photoelectric interconnected circuits.