An Investigation Of The Preparation Of Fluorine Doped Tin Oxide Films By Chemical Vapor Deposition And Their Properties

Transparent conducting oxides (TCOs) are a unique class of materials characterized by the coexistence of both high optical transparency and high electrical conductivity. Due to these unusual properties, they are widely applied in flat panel display, photovoltaics, low-e windows, and electrochromic windows. The most common industrial TCO is fluorine doped tin oxide (FTO), which has advantages of low cost, good chemical stability and high mechanical strength. Atmospheric pressure chemical vapor deposition (APCVD) is widely used to synthesize FTO thin films because it is suitable for large-scale production at low cost.In this thesis, we deposit FTO thin films on glass substrates by APCVD. Such films with an excellent combination of high surface roughness, high optical transparency and high electrical conductivity can be obtained by using tin tetrachloride (TTC) as Sn precursor. The roughness can reach37nm at a film thickness of300nm. The properties of FTO thin films could be optimized by changing the experimental conditions to improve the light trapping and thus the efficiency of solar cells. In addition, different tin compounds are used as precursors to deposit FTO thin films. Films with good properties can be achieved by changing the experimental conditions, especially by adding HC1, leading to a resistivity of10-4Ω·cm, the lowest level ever reported. These techniques for preparing high roughness and low resistivity FTO thin films pave the way for further investigations and applications.