Open AccessEffect of post deposited annealing ambience and temperature on the longer visible absorption of zinc oxide films
Author(s) -
V. Rakhesh,
Aparna S. Devan,
Balakrishnan Shankar
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/577/1/012139
Subject(s) - zinc , annealing (glass) , materials science , absorbance , analytical chemistry (journal) , absorption (acoustics) , band gap , deposition (geology) , oxide , attenuation coefficient , substrate (aquarium) , oxygen , chemistry , metallurgy , composite material , optics , chromatography , optoelectronics , paleontology , physics , oceanography , sediment , biology , geology , organic chemistry
Zinc oxide films were deposited on heated glass substrates at different substrate temperature 450°C and 500°C. After the deposition, some samples were heat treated at 500°C for one hour in air and some samples in vacuum for one hour at the same temperature. Absorbance analysis revealed that as deposited samples and post heat treated samples are showing intense absorption near 1.5eV apart from that corresponding to band gap of ZnO. The absorption coefficient variation with incident energy for the samples annealed in vacuum after deposition at 450° suggested the presence of oxygen vacancy as the native defect for the absorption near 1.5eV. The absorption energy for the samples obtained from (αhν)2 vs energy plot suggested that same kind of defect may be present in all the samples and is around 1.53eV.