【Device Papers】High performance of self-powered Ga₂O₃:Si/p-GaN heterojunction UV photodetectors

      Researchers from the Vietnam Academy of Science and Technology have published a dissertation titled "High performance of self-powered Ga₂O₃:Si/p-GaN heterojunction UV photodetectors" in Materials Science in Semiconductor Processing.

Abstract

      High performance ultraviolet (UV) photodetectors have garnered much interest for their wide range of potential in uses. On the basis of this, a self-powered UV photodetectors (PDs) based on β-Ga₂O₃:Si/p-GaN heterojunctions were fabricated by pulsed laser deposition (PLD) system equipped with a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser at wavelength center of 266 nm. Then, the Ga₂O₃ (99.9 %) doped with 0.1 wt% Si was used as source to deposit Ga₂O₃:Si thin films on the p-GaN layer, which were deposited on c-sapphire substrates by sputtering technique. The high quality of β-Ga₂O₃:Si thin films are formed by well controlling the oxygen pressure during deposition, which significantly enhances the device performance. In the self-powered mode with the bias voltage of 0V, the photodetectors fabricated under oxygen pressure of 5 mTorr with low dark current of 0.6 nA, high photoresponsivity and detectivity of 2.44 × 10⁻² A/W and 2.45 × 10¹¹ cmHz^1/2W, respectively. This study represents one of the initial self-powered UV photodetectors with unique properties, which greatly enhances the progress of multifunctional UV photodetectors.

DOI：

https://doi.org/10.1016/j.mssp.2025.109479