Abstract
Here, we report on Si-based color photodetectors using monolithically integrated metal-insulator-metal Fabry-Perot cavity top contacts. Contacts were formed by depositing Ag/SiO2/Ag layers with different oxide thicknesses for each color. This allowed controlling the transmission band position and width while maintaining the high conductivity. We have obtained over 55% external quantum efficiency for different colors both numerically and experimentally. The FWHM was less than 50 nm and the rejection ratio was an order of magnitude for each color. The total transmission through these top contacts exceeded that of dye filters used in conventional color CCDs and CMOS imaging arrays. In addition, these contacts performed similarly to recently proposed plasmonic hole array filters without the necessity of complicated fabrication steps like FIB milling and e-beam lithography. This type of top contacts can serve as a cheap alternative to dye filters used in contemporary devices without making the fabrication complicated.
| Original language | English (US) |
|---|---|
| Article number | 223102 |
| Journal | Journal of Applied Physics |
| Volume | 120 |
| Issue number | 22 |
| DOIs | |
| State | Published - Dec 14 2016 |
Funding
This material is based upon work supported by the AFOSR under Award No. FA9550-12-1-0280. This research was also partially supported by the Materials Research Science and Engineering Center (NSF-MRSEC) (DMR-1121262) of Northwestern University. K.A. acknowledges the partial support from the Institute for Sustainability and Energy at Northwestern (ISEN) through ISEN Booster Award. This research made use of the NUANCE Center at Northwestern University, which was supported by NSF-NSEC, NSF-MRSEC, Keck Foundation, and the State of Illinois and the NUFAB cleanroom facility at Northwestern University.
ASJC Scopus subject areas
- General Physics and Astronomy