@article{Wang2023, 
author = {Yue Wang and Haoran Sun and Zhe Sheng and Jianguo Dong and Wennan Hu and Dongsheng Tang and Zengxing Zhang},
title = {Van der Waals contacted WSe2 ambipolar transistor for in-sensor computing},
year = {2023},
journal = {Nano Research},
volume = {16},
number = {11},
pages = {12713-12719},
keywords = {ambipolar transistor, van der Waals contact, reconfigurable photodiode, in-senor computing},
url = {https://www.sciopen.com/article/10.1007/s12274-023-6128-6},
doi = {10.1007/s12274-023-6128-6},
abstract = {Image sensors with an in-sensor computing architecture have shown great potential in meeting the energy-efficient requirements of emergent data-intensive applications, where images are processed within the photodiode arrays. It demands the composed photodiodes are reconfigurable, which are usually achieved by ambipolar two-dimensional (2D) semiconductors. To improve the ambipolar charges injection, here we report a top-gated field-effect transistor (FET) design that is of bottom van der Waals contact via transferring ambipolar 2D WSe2 onto Pd/Cr source/drain electrodes. The devices exhibit nearly negligible effective barrier heights for both holes and electrons based on thermionic emission mode, and show an almost balanced on/off ratio in the p-branch and n-branch. By replacing the top gate with two aligned semi-gates, the devices can effectively function as reconfigurable photodiodes. They can be switched between PIN and NIP configurations via controlling the two semi-gates, exhibiting good linearity in terms of short-circuit current (ISC) and incident light power density. The photodiode arrays are also demonstrated for in-sensor optoelectronic convolutional image processing, showing significant potential for in-sensor computing image processors.}
}