p-Cu2O-shell/n-TiO2-nanowire-core heterostucture photodiodes
- Equal contributors
1 Institute of Microelectronics and Department of Electrical Engineering, Center for Micro/Nano Science and Technology, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, 701, Taiwan
2 National Nano Device Laboratories, Tainan, 741, Taiwan
3 Department of Electronic Engineering, National University of Tainan, Tainan, 700, Taiwan
Nanoscale Research Letters 2011, 6:575 doi:10.1186/1556-276X-6-575Published: 31 October 2011
This study reports the deposition of cuprous oxide [Cu2O] onto titanium dioxide [TiO2] nanowires [NWs] prepared on TiO2/glass templates. The average length and average diameter of these thermally oxidized and evaporated TiO2 NWs are 0.1 to 0.4 μm and 30 to 100 nm, respectively. The deposited Cu2O fills gaps between the TiO2 NWs with good step coverage to form nanoshells surrounding the TiO2 cores. The p-Cu2O/n-TiO2 NW heterostructure exhibits a rectifying behavior with a sharp turn-on at approximately 0.9 V. Furthermore, the fabricated p-Cu2O-shell/n-TiO2-nanowire-core photodiodes exhibit reasonably large photocurrent-to-dark-current contrast ratios and fast responses.