Boosting the Performance of β‐Ga₂O₃ Solar‐Blind Deep UV Photodetectors by Balancing the Photocurrent and Dark Current via the IZO Interlayer

Abstract

There is a tradeoff between the high photocurrent and the low dark current for the gallium oxide (Ga2O3) metal–semiconductor–metal photodetectors (PDs). Achieving a balance between the photocurrent and dark current is crucial to the final device's performance. Herein, indium zinc oxide (IZO) is introduced between the Ga2O3 and the metal contact for the first time. By adjusting the IZO interlayer thickness and the annealing temperature, the barrier height between Ga2O3 and the metal contact can be well controlled. In detail, the β‐Ga2O3 film is epitaxially grown by mist chemical vapor deposition, and the different thicknesses of IZO are deposited under Ti/Au electrode. The devices with 10 nm IZO interlayer and 300 °C annealing temperatures have an obvious device performance improvement, which has achieved responsivity (R) of 508 A W−1, a high peak detectivity (D*) of 2.65 × 1015 Jones, and a raised‐up relaxation time of 0.25 s (fast) and 1.22 s (slow). Compared with the device without IZO, the performances get obviously enhanced. Hence, the work hopes to promote the development of the β‐Ga2O3 solar‐blind deep UV PDs.