Ultraviolet Detector Based on $\hbox {SrZr}_{0.1} \hbox {Ti}_{0.9}\hbox {O}_{3}$ Film

In this letter, a nanocrystalline SrZr_0.1Ti_0.9 O₃thin film was synthesized by sol-gel method and characterized by means of X-ray diffraction, X-ray photoelectron spectroscopy, atomic force microscopy, and UV-visible absorption spectra. Interdigitated Au electrodes were deposited on the film to fabricate metal-semiconductor-metal ultraviolet photodetector. At 5-V bias, the dark current of the device was 41 pA. Under the irradiation of 260-nm UV light, peak responsivity of 94 mA/W was achieved, which was higher than that of pure SrTiO₃-based photodetectors. The higher responsivity of the SrZr_0.1Ti_0.9O₃ device may be due to the introduction of zirconia, which would induce more oxygen vacancies. The UV/visible rejection ratio R₂₆₀ nm/R₃₈₀ nm was more than three orders of magnitude, indicating excellent sensitivity. The rise time and fall time of the device were 3.8 and 565 ms, respectively.