Fabrication AlGaN/GaN MIS UV Photodetector by H<sub>2</sub>O<sub>2</sub> Oxidation

Abstract

This letter demonstrates and investigates AlGaN/GaN metal–insulator–semiconductor ultraviolet photodetector (MIS-UV-PD) with a cost-effective wet oxidation technique. The H2O2 oxidation technique is adopted to grow an insulator layer. The material qualitative and semiquantitative analyses of the H2O2-grown aluminum oxide are studied by energy dispersive X-ray spectroscopy The performances of the present MIS-UV-PD with different H2O2 treatment time are also investigated. The MIS-PD with 5-min H2O2 treatment time has the optimum performances. The dark current is suppressed from 4.23 nA to 5.15 pA at −10 V. The responsivity and the UV to visible rejection ratio are enhanced to $1.03\times 10^{\mathrm {\mathbf {-2}}}$ A/W and $3.38\times 10^{\mathrm {\mathbf {5}}}$ . Moreover, the noise equivalent power and detectivity are determined to be $4.8\times 10^{\mathrm {\mathbf {-11}}}$ W and $4.52\times 10^{\mathrm {\mathbf {10 }}}$ cmHz $^{\mathrm {\mathbf {0.5}}}$ W $^{\mathrm {\mathbf {-1}}}$ . This cost-effective oxidation technique provides a simple approach to fabricate AlGaN/GaN MIS-UV-PD and its performances are also improved.