Fast Photoresponse and Long Lifetime UV Photodetectors and Field Emitters Based on ZnO/Ultrananocrystalline Diamond Films
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2015-09-18 |
| Journal | Chemistry - A European Journal |
| Authors | Adhimoorthy Saravanan, BohrâRan Huang, JunâCheng Lin, Gerd Keiser, IâNan Lin |
| Institutions | Boston University, National Taiwan University of Science and Technology |
| Citations | 25 |
Abstract
Section titled âAbstractâAbstract We have designed photodetectors and UV field emitters based on a combination of ZnO nanowires/nanorods (ZNRs) and bilayer diamond films in a metal-semiconductor-metal (MSM) structure. The ZNRs were fabricated on different diamond films and systematic investigations showed an ultraâhigh photoconductive response from ZNRs prepared on ultrananocrystalline diamond (UNCD) operating at a lower voltage of 2 V. We found that the ZNRs/UNCD photodetector (PD) has improved field emission properties and a reduced turnâon field of 2.9 V ÎŒm â1 with the highest electron field emission (EFE) by simply illuminating the sample with ultraviolet (UV) light. The photoresponse ( I photo / I dark ) behavior of the ZNRs/UNCD PD exhibits a much higher photoresponse (912) than bare ZNRs (229), ZNRs/nanocrystalline diamond (NCD; 518), and ZNRs/microcrystalline diamond (MCD; 325) under illumination at λ =365 nm. A photodetector with UNCD films offers superior stability and a longer lifetime compared with carbon materials and bare ZNRs. The lifetime stability of the ZNRs/UNCDâbased device is about 410 min, which is markedly superior to devices that use bare ZNRs (92 min). The ZNRs/UNCD PD possesses excellent photoresponse properties with improved lifetime and stability; in addition, ZNRs/UNCDâbased UV emitters have great potential for applications such as cathodes in flatâpanel displays and microplasma display devices.