title: Ultraviolet photodetector with high internal gain enhanced by TiO₂/SrTiO₃ heterojunction.
abstract: In this letter, TiO₂ nanocrystalline film was prepared on SrTiO₃ (001) substrate to form an n-n heterojunction active layer. Interdigitated Au electrodes were deposited on the top of TiO₂ film to fabricate modified HMSM (heterojunction metal-semiconductor-metal) ultraviolet photodetector. At 10 V bias, the dark current of the detector was only 0.2 nA and the responsivity was 46.1 A/W at 260 nm. The rise and fall times of the device were 3.5 ms and 1.4 s, respectively. The TiO₂/SrTiO₃ heterojunction contributed a lot to the high responsivity and reduced the fall time, which improved the device performance effectively. These results demonstrate the excellent application of TiO₂/SrTiO₃ heterojunction in fabricating high performance UV photodetectors.
authors.affiliation: State Key Laboratory on Integrated Optoelectronics, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.forename: Kaibo
authors.initials: K
authors.lastname: Lv
authors.forename: Weiyou
authors.initials: W
authors.lastname: Chen
authors.forename: Jingran
authors.initials: J
authors.lastname: Zhou
authors.forename: Liang
authors.initials: L
authors.lastname: Shen
authors.forename: Shengping
authors.initials: S
authors.lastname: Ruan
mesh_terms: D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D010087:Oxides / Q000737:chemistry* / Q000528:radiation effects; D010783:Photometry / Q000295:instrumentation*; D012666:Semiconductors; D013324:Strontium / Q000737:chemistry* / Q000528:radiation effects; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D010087:Oxides; C009495:titanium dioxide; D014025:Titanium; C119252:strontium titanium oxide; D013324:Strontium