Oxygen partial pressure induced effects on the microstructure and the luminescence properties of pulsed laser deposited TiO2 thin films

Autor: Shailendra Kumar Sharma, Sanjeev Sharma, Dr. KOPPOLE CHANDRA SEKHAR, Maria de Jesus de Matos Gomes, ARUP KUNTI, Mário António Caixeiro de Castro Pereira
Přispěvatelé: Universidade do Minho
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: AIP Advances, Vol 7, Iss 1, Pp 015021-015021-8 (2017)
Repositório Científico de Acesso Aberto de Portugal
Repositório Científico de Acesso Aberto de Portugal (RCAAP)
instacron:RCAAP
Popis: In this work, the influence of oxygen partial pressure on structural, morphological, and optical properties of TiO2 thin films grown on fused quartz substrate at different oxygen partial pressure by pulsed laser deposition were examined. X-Ray diffraction (XRD) patterns show the formation of TiO2 anatase phase deposited at high oxygen pressure. Atomic Force Microscopy (AFM) reveals that surface roughness of the films increases with oxygen pressure. Variation of surface morphology of films with increasing oxygen partial pressure was studied by AFM. It is observed that energy band gap of the films increases from 3.27 eV to 3.52 eV with the increase of oxygen pressure and is attributed to the decrease of oxygen defects. TiO2 thin films exhibited blue emission under the excitation of 320 nm wavelength. De-convoluted photoluminescence (PL) peaks showed that defect states are responsible for visible emission in TiO2 thin films. The intensity of PL emission associated with oxygen vacancies decreases with increasing oxygen pressure. Photometric characteristic analysis shows that the films deposited 1x10-4 mbar oxygen pressure exhibited intense blue emission with high luminescence efficacy of radiation.
A. K. Kunti is thankful to European Union for providing the Erasmus Mundus Doctoral exchange programme fellowship under AREAS+ project at University of Minho, Braga, Portugal. Authors are also thankful to Mr. Sourav Chakraborty and Central Research Facility, IIT (ISM), Dhanbad, India for AFM measurements.
info:eu-repo/semantics/publishedVersion
Databáze: OpenAIRE