Electrical and Optical Characteristics of UV Photodetector With Interlaced ZnO Nanowires

摘要

A zinc oxide (ZnO) nanowire (NW) photodetector was fabricated with a simple method by bridging the gap of interdigitated gallium-doped ZnO pattern deposited on a silicon oxide ( $hbox{SiO}_{2}$) thin film with interlaced ZnO NWs. With an incident wavelength of 375 nm, it was found that measured responsivity was 0.055 A/W for the interlaced ZnO NWs photodetector with a 1 V applied bias. The transient time constants measured during the turn-on and turn- off states were $tau_{{rm ON}} = hbox{12.72 ms}$ and $tau_{{rm OFF}} = hbox{447.66 ms}$ , respectively. Furthermore, the low-frequency noise spectra obtained from the ultraviolet photodetector were purely due to the 1/$f$ noise. Besides, the noise equivalent power and normalized detectivity ($D^*$) of the ZnO NW photodetector were $hbox{2.32} times hbox{10}^{-9} hbox{W}$ and $hbox{7.43} times hbox{10}^{9} hbox{cm}{cdot}hbox{Hz}^{0.5}{cdot}hbox{W}^{-1}$, respectively.