PLD Prepared Si-rich Silica Thin Film At Low Temperature And Its Application

Silicon is the foundational material of the semiconductor IC industry. Due to its excellent electrical, thermal and chemical stability, it plays a significant and irreplaceable role in the rapidly developmental field of microelectronics in the past few decades. Silicon-rich silicon dioxide film, a kind of nc-Si thin film, because of its important features of electroluminescence and photoluminescence in range of visible light, as a potential material of integrated silicon optoelectronic devices has been get the attention. SiO₂ thin film ,because of its good performance of chemical-mechanical thermal, has been widely used in filed of integrated circuit,optoelectronics,packaging materials.In this paper, pulsed laser deposition (PLD) systems were used to prepare the silicon-rich SiO₂ thin film. By using the thin film characterization techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS),Infrared spectroscopy (IR), Raman spectroscopy (Raman) and atomic force microscope (AFM) , discussing the influences of process conditions such as sputtering power, oxygen flow, annealing temperature on the thin-film structure, composition and particle size.the Cu/SiO₂/P-Si plate capacitor was prepared, the influence of oxygen flow and test frequency in leakage current and C-V characteristics were discussed. Finally, according to the good mechanical, chemical and thermal properties of SiO₂ film, we studied their applications in the fields such as the buffer layer of glass-based ZnO thin film, the substrate protective layer of flexible optical display device and the corrosion-resistant layer of metal filmThe experimental results show that: (1) silica thin films are prepared at room temperature by using PLD method, and the SiOx films have different components (Si:O=1.1-2) (2) Through the XRD, XPS, Raman spectroscopy, we can proved that the existence of nano-silicon in thin films. The average particle diameter estimated by XRD and Raman were 6.8 nm and 5.0nm respectively. (3) AFM results show that surface roughness (RMS) of SiO₂ film reduced significantly with the oxygen flow increase from 1 to 20(sccm), , indicating that the increase of oxygen flow has positive impact to the surface roughness of silicon oxide (4) The leakage current of Cu/SiO₂/P-Si plate capacitor reduces an order of magnitude from 10-4 to 10-5 (mA), indicating that the better of surface roughness,the less of leakage current of silicar reduces (5) The results show that the introduction of buffer layer has improved the crystallization quality and electrical properties of the glass-based ZnO thin film; flexible substrate coated with a layer of SiO₂ thin film, without reduceing its translucent, plays a role of protection layer of substrate ; SiO₂ thin film has a good performance on the anti-corrosion layer of metal film in particular, anti-acid corrosion layer.