Electron-hole recombination on ZnO(0001) single-crystal surface studied by time-resolved soft X-ray photoelectron spectroscopy

Journal Article · Mon Oct 13 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4897934· OSTI ID:22350884

Yukawa, R.; Yamamoto, S.; Ogawa, M.; Yamamoto, Sh.; Fujikawa, K.; Hobara, R.; Ozawa, K. ^[1]; Emori, M.; Sakama, H. ^[2]; Kitagawa, S.; Daimon, H. ^[3]

---

1. Department of Chemistry and Materials Science, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8551 (Japan)
2. Department of Physics, Sophia University, Chiyoda-ku, Tokyo 102-8554 (Japan)
3. Nara Institute of Science and Technology (NAIST), Ikoma, Nara 630-0192 (Japan)

Time-resolved soft X-ray photoelectron spectroscopy (PES) experiments were performed with time scales from picoseconds to nanoseconds to trace relaxation of surface photovoltage on the ZnO(0001) single crystal surface in real time. The band diagram of the surface has been obtained numerically using PES data, showing a depletion layer which extends to 1 μm. Temporal evolution of the photovoltage effect is well explained by a recombination process of a thermionic model, giving the photoexcited carrier lifetime of about 1 ps at the surface under the flat band condition. This lifetime agrees with a temporal range reported by the previous time-resolved optical experiments.

• OSTI ID: 22350884
• Journal Information: Applied Physics Letters, Vol. 105, Issue 15; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CARRIER LIFETIME
DEPLETION LAYER
ELECTRONIC STRUCTURE
HOLES
MONOCRYSTALS
PHOTOELECTRON SPECTROSCOPY
RECOMBINATION
RELAXATION
SOFT X RADIATION
SURFACES
TIME RESOLUTION
ZINC OXIDES