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

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 beta-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 degrees C annealing temperatures have an obvious device performance improvement, which has achieved responsivity (R) of 508 AW(-1), a high peak detectivity (D*) of 2.65 x 10(15) 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 beta-Ga2O3 solar-blind deep UV PDs.

Automated summary

The introduction of indium zinc oxide (IZO) in gallium oxide (Ga2O3) metal-semiconductor-metal photodetectors (PDs) allows for better control of the barrier height between Ga2O3 and the metal contact, achieving a balanced performance between photocurrent and dark current.