Fluorine doped tin oxide (FTO) thin films were deposited onto glass substrate at different substrate temperatures by a simple and inexpensive method of air pressure chemical vapor deposition. The substrate temperature was kept constant at about 500• C as the optimum temperature, and air was used as both a carrier gas and the oxidizing agent. A very simple method of characterization were carried on to investigate the electrical and structural properties of the prepared thin films. The electrical parameters variations showed that these parameters vary with substrate temperature ranging from an insulator thin film to a highly conductive layer. X-ray diffraction also revealed the structure to be polycrystalline at higher temperatures compared to amorphous structure for lower temperatures.

Nanostructured undoped zinc oxide (ZnO) thin films were deposited using atmospheric pressure chemical vapor deposition (APCVD) on glass substrates using zinc acetate dehydrate [C 4 H 6 O 4 Zn·2H 2 O, ZnAc] in less than 2 minutes for each sample. In order to reduce the resistivity of ZnO films, a very thin layer of Ag was deposited on top of the films via the sputtering method to reduce resistivity from 2.89 to 0.31 Ω.cm, using only a 30Å silver coating. Structural, electrical and optical properties of the resulting bilayers were also investigated. The results show a polycrystalline structure in higher temperatures compared to rather amorphous ones in lower temperatures such as 325℃. The XRD patterns of the optimum polycrystalline films were identified as a hexagonal wurtzite structure of ZnO with the (002) preferred orientation. Also, sheet resistance decreased from 17.8 MΩ/⧠ to 28.9 KΩ/⧠ for the temperatures of 325℃ to 450℃, respectively. Based on the physical properties of undoped ZnO, substrate temperature is an important factor which affects the crystallite size and modifies electrical parameters. UV-vis measurements revealed a reduction in the transparency of the layers with increasing substrate temperature. A sharp cut-off was observed in ultraviolet regions at around 380 nm.

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