TiO2-x-enhanced IR hot carrier based photodetection in metal thin film-si junctions
| Autor: | Takayuki Matsui, Anna Regoutz, Ryan Bower, Nicholas A. Güsken, Brock Doiron, Stefan A. Maier, Rupert F. Oulton, Alberto Lauri, Lesley F. Cohen, Peter K. Petrov, Yi Li, Andrei P. Mihai |
|---|---|
| Přispěvatelé: | Engineering & Physical Science Research Council (E, The Leverhulme Trust, Engineering and Physical Sciences Research Council |
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Technology
Materials science Silicon Materials Science chemistry.chemical_element Materials Science Multidisciplinary 02 engineering and technology Photodetection CMOS compatible TiN thin films 01 natural sciences Physics Applied 010309 optics chemistry.chemical_compound Electrical resistivity and conductivity 0103 physical sciences TiO2-x EXCITATION Electrical and Electronic Engineering Thin film Nanoscience & Nanotechnology Photocurrent Science & Technology business.industry Physics Optics TRAPS 021001 nanoscience & nanotechnology Titanium nitride Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials Amorphous solid chemistry Physics Condensed Matter REFRACTORY PLASMONICS sub-bandgap photodetection Physical Sciences Optoelectronics Science & Technology - Other Topics TIO2 hot carriers 0210 nano-technology business Tin Biotechnology GENERATION |
| Popis: | We investigate titanium nitride (TiN) thin film coatings on silicon for CMOS-compatible sub-bandgap charge separation upon incident illumination, which is a key feature in the vast field of on-chip photodetection and related integrated photonic devices. Titanium nitride of tunable oxidation distributions serves as an adjustable broadband light absorber with high mechanical robustness and strong chemical resistivity. Backside-illuminated TiN on p-type Si (pSi) constitutes a self-powered and refractory alternative for photodetection, providing a photoresponsivity of about ∼1 mA/W at 1250 nm and zero bias while outperforming conventional metal coatings such as gold (Au). Our study discloses that the enhanced photoresponse of TiN/pSi in the near-infrared spectral range is directly linked to trap states in an ultrathin TiO2–x interfacial interlayer that forms between TiN and Si. We show that a pSi substrate in conjunction with a few nanometer thick amorphous TiO2–x film can serve as a platform for photocurrent enhancement of various other metals such as Au and Ti. Moreover, the photoresponse of Au on a TiO2–x/pSi platform can be increased to about 4 mA/W under 0.45 V reverse bias at 1250 nm, allowing for controlled photoswitching. A clear deviation from the typically assumed Fowler-like response is observed, and an alternative mechanism is proposed to account for the metal/semiconductor TiO2–x interlayer, capable of facilitating hole transport. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|