Microstructural characterization of sol-gel derived Ga/sub 2/O/sub 3/-TiO/sub 2/ thin films for gas sensing

Y.X. Li1, D. Wang2, Q.R. Yin2, K. Galatsis1, W. Wlodarski1
1School of Electrical and computer Systems Engineering, RMIT University, Melbourne, VIC, Australia
2Laboratory of Functional Inorganic Materials, SICCAS, Shanghai, China

Tóm tắt

Binary TiO/sub 2/-Ga/sub 2/O/sub 3/ thin films were prepared from the sol-gel process. Titanium butoxide and gallium isopropoxide were used as precursor materials. The mixed solution was spun onto the sapphire and silicon substrates at 2500 rpm for 30 s to prepare thin films. The X-Ray Diffraction (XRD) results revealed that the films annealed at a temperature of 500/spl deg/C for 1 hr is /spl gamma/-Ga/sub 2/O/sub 3/ structure. Scanning Electronic Microscope (SEM) images revealed that the film surface is smooth with grains in a nanometer scale. The film showed good responses to 100 ppm, 1000 ppm and 1% O/sub 2/ at an operating temperature of 470/spl deg/C. The resistance of Ga-doped TiO/sub 2/ film is between the resistances of pure TiO/sub 2/ and Ga/sub 2/O/sub 3/ films. The response of Ga-doped TiO/sub 2/ thin film is sensitive, fast and stable to oxygen gas.

Từ khóa

#Gallium #Transistors #Temperature #Scanning electron microscopy #Titanium #Silicon #Substrates #Semiconductor thin films #X-ray imaging #X-ray diffraction

Tài liệu tham khảo

10.1016/S0925-4005(01)00668-2 lang, 1998, The technical digest of The 7 International Meeting on Chemical Sensors, 864 0 10.1016/S0040-6090(97)00401-X harwig, 1976, Solid State Communications, 18, 1223, 10.1016/0038-1098(76)90944-3 kiss, 1999, The 13th European Conference on Solid-State Transducers 10.1016/0040-6090(90)90132-W