Researchers create unipolar barrier photodetectors based on 2D layered materials
— Read on techxplore.com/news/2021-06-unipolar-barrier-photodetectors-based-2d.html

A Game Changer Technology….

Since Bell Labs produced the Si-based PN junction in 1935, using the built-in  in the depletion region has become the main technical route to block dark current,” Weida Hu and Peng Zhou, two of the researchers who carried out the study, told Tech Xplore via email. “In traditional PN junctional infrared photodetectors, the high Shockley-read-Hall (SRH) recombination and surface recombination in the depletion region seriously limit the suppression of dark current. In response to these issues, engineers introduced a new device structure beyond the PN junction, namely the unipolar barrier structure.”

The key idea behind the paper authored by Hu, Zhou and their colleagues is that vdW unipolar barrier heterostructures can be used to suppress dark current inside photodetectors. By blocking majority carriers, in fact, these structures could ultimately allow infrared photodetectors to operate at high temperatures, achieving remarkable performances.

“The proposed novel vdW unipolar barrier heterostructures could be a solution to the bottleneck of dark current in infrared photodetectors and further improve the performance of infrared photodetectors,” Hu and Zhou said. “Eventually, they could thus facilitate the ‘lab-to-fab’ transition of two-dimensional (2D) materials in infrared applications.”