화학공학소재연구정보센터
Thin Solid Films, Vol.517, No.11, 3253-3256, 2009
Effect of growth temperature on the structural and transport properties of magnetite thin films prepared by pulse laser deposition on single crystal Si substrate
Magnetite (Fe(3)O(4)) thin films are prepared by pulsed laser deposition using an alpha-Fe(2)O(3) target on silicon (111) substrate in the substrate temperature range of 350 degrees C to 550 degrees C. X-ray diffraction (XRD) measurement shows that the film deposited at 450 degrees C is a single phase Fe(3)O(4) film oriented along [111] direction. However, the film grown at 350 degrees C reveals mixed oxide phases (FeO and Fe(3)O(4)), while the film deposited at 550 degrees C is a polycrystalline Fe(3)O(4). X-ray photoelectron spectroscopy study confirms the XRD findings. Raman measurements reveal identical spectra for all the films deposited at different substrate temperatures. We observe abrupt increase in the resistivity behavior of all the films around Verwey transition temperature (T(V)) (125 K-120 K) though the transition is broader in the film deposited at 350 degrees C. We observe that the optimized temperature for the growth of Fe(3)O(4) film on Si is 450 degrees C. The electrical transport behavior follows Shklovskii and Efros variable range hopping type conduction mechanism below T(V) for the film deposited at 450 degrees C possibly due to the granular growth of the film. (C) 2008 Elsevier B.V. All rights reserved.