Influence of titanium adhesion layer on performance of beta-Ga2O3 solar-blind photodetector

Abstract

The influence of a titanium (Ti) adhesion layer on the ductility of thin Au film well bonded with beta-Ga2O3 film on a flexible substrate were investigated with the quality of beta-Ga2O3 deep-ultraviolet photodetector. The photodetector fabricated with Ti adhesion layer exhibits excellent photoelectric performance and stability. The photocurrent obtained by the Ti/Au bilayer-device (3.1 x 10(-8) A) is significantly greater than that of an Au electrode-device (1.7 x 10(-8) A) at 10 V under a flat state. After 250 bending cycles, the photoresponsivity of the Au electrode-device declined approximately 20 times, while little photoresponsivity degradation was observed in the Ti/Au bilayer-device. Additionally, more suppression of the deformation and cracks was observed in the Au film with Ti adhesion layer than the Au grown directly on the beta-Ga2O3 films. These results reveal the importance of the adhesion layer in promoting the photodetector.