화학공학소재연구정보센터
Journal of Vacuum Science & Technology A, Vol.21, No.4, 979-982, 2003
Raman and photoluminescence of ZnO films deposited on Si(111) using low-pressure metalorganic chemical vapor deposition
The highly c-oriented ZnO films were epitaxially grown on n-type Si (111) substrate at the temperature range of, 340-460 degreesC using the low-pressure metalorganic chemical vapor deposition method. All films exhibit a pronounced (002) peak for ZnO, indicative of the strong c-axis oriented characteristic. The ZnO film grown at 400 degreesC shows the best structural quality along with the largest lateral grain size, well supported by the narrowest full. width at half maximum of ZnO (002) peak about 0.19degrees in x-ray diffraction. However, the temperature dependence of the vibrational modes, at 436 and similar to563 cm(-1) in Raman spectra revealed a low density of oxygen vacancies in the films grown at low temperatures, which is supposed to determine the photoluminescence (PL) properties. At low temperatures, the narrow ultraviolet (UV) near band emission dominated the PL spectrum with a very weak low energy tail near the band. High temperature (up to 460degreesC) would cause serious oxygen deficiency, resulting in the weak broad CV band with obvious blue band emission. (C) 2003 American Vacuum Society.