FABRICATING BARIUM DISILICIDE THIN-FILMS ON GERMANIUM SUBSTRATE AND INVESTIGATING SOME OF ITS PROPERTIES
Corresponding Author(s) : Mai Thi Kieu Lien
UED Journal of Social Sciences, Humanities and Education,
Vol. 9 No. 4 (2019): UED JOURNAL OF SOCIAL SCIENCES, HUMANITIES AND EDUCATION
BaSi2 thin-films were fabricated by thermal evaporation method on flat and modified Ge substrates with various etching times te. Continuing with the previous study, the crystalline properties and minority carrier-lifetimes τ in BaSi2 thin-films were investigated respectively. The obtained results showed that, the film quality slightly degrades toward the film surface. τ of the BaSi2 films grown on modified substrates are longer than those on flat substrate and reaches 3.17 µs at te = 15 mins. This is the highest value obtained while measuring the thin BaSi2 films (thickness < 300 nm) evaporating and condensing onto various substrates. The results obtained in this study contribute to strengthening the conclusions about the optimal etching time in the previous study. Photoluminescence spectra of BaSi2 films on Ge substraes showed that BaSi2 film deposited on modified substrate with te = 15 mins has better crystalline quality than that on the flat one. The experimental bandgap of BaSi2 thin-films was deduced, reaching the value of 1.17-1.2 eV.
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