High-sensitivity SrTiO₃ photodetectors with paralleled multiple interdigital electrode cells

We report high-sensitivity SrTiO₃ photoconductive detectors with multiple photoelectric cells connected in parallel. The photocurrent of the detectors increases significantly with an increase of the cell number. The photocurrent responsivity of the detector with three cells can reach 237 mA/W at 10 V bias under illumination of the 375 nm laser, and the corresponding quantum efficiency is 77% at 10 V bias. Furthermore, a transient photovoltaic signal with a rise time of ∼490 ps and a full width at halfmaximum of ∼900 ps is obtained. These results demonstrate that the present devices with further improvement of performance have great potential application in high-sensitivity and ultrafast ultraviolet photodetectors.