We fabricate an ultraviolet photodetector based on a blend of poly (N-vinylcarbazole) (PVK) and 2-tert-butylphenyl-5-biphenyl-1,3, 4-oxadiazole (PBD) using spin coating. The device exhibites a low dark current density of 2.2 \times 10?3 \muA/cm2 at zero bias. The spectral response of the device shows a narrow bandpass characteristic from 300 to 355 nm, and the peak response is 18.6 mA/W located at 334 nm with a bias of -1 V. We also study the performances of photodetectors with different blend layer thicknesses. The largest photocurrent density is obtained with a blend of 90 nm at the same voltage.
© 2011 Chinese Optics Letters
(250.2080) Optoelectronics : Polymer active devices
(310.1860) Thin films : Deposition and fabrication
(310.6845) Thin films : Thin film devices and applications
(250.0040) Optoelectronics : Detectors
Jian Sun, Kuanjun Peng, Lu Zhu, Zuofu Hu, Qian Dai, Xiqing Zhang, and Yongsheng Wang, "Ultraviolet photodetector with bandpass characteristic based on a blend of PVK and PBD," Chin. Opt. Lett. 9, 052501- (2011)