구성 및 성능 200㎜ × 200㎜ 한글키워드 플라즈마 화학기상증착기 영문키워드 PECVD PECVD 란 ? PECVD system is batch-production equipment that supports the application of silicon based thin film process offering step coverage and gap filling required during semiconductor fabrication and solar cell device processes, including the applications of passivation, isolation and dielectric insulation depositions. The use of perfluorinated gases such as NF3, CF4 or SF6 for PECVD (plasma enhanced chemical vapor deposition) chamber cleaning has a much higher impact on global warming than does the use of onsite-generated F2. This holds true even when supposing that in the future much more effort is paid for the correct abatement and a leak-free supply and take-back chain. This paper will discuss the steps available to the PV industry for control and reduction of carbon emissions in the chamber cleaning process. PECVD. Plasma Enhanced Chemical Vapor Deposition is mainly used for the deposition of dielectric films and passivation films like silicon oxide or nitride or ONO layers at low temperature. It can be also used for SiC layers of poly-Silicon deposition. The necessary energy for the chemical reaction is not introduced by heating the whole reaction chamber but just by heated gas or plasma. It is the best method, if dopant diffusion has to be kept low, wafers have to be treated, which are sensible to high temperature or have been aluminium metallized already. The thermal budget of the treated wafers stays low with PECVD. Using an RF generator, the plasma is formed in the reaction chamber. It contains reactive ions and radicals. The growth of the deposit starts easily because of the activation and cleaning of the surface by the more of less intense bombarding with ions from the plasma. You get good adhesion and high growth rates. The properties of the coated layers can be better influenced with PECVD than in simply thermal deposition technique, because more process parameters can be varied. Important are the adjustment of adhesion, compressive and tensile stress causing warpage, hydrogen content and density, etchability, etch rate and selectivity in etching, step coverage as well as stoichiometry (consistence) and cleanliness of the deposited layers, which can be measured by the refractive index. The maximum thickness of the deposit and the best uniformity of the coating is also dependent of the PECVD process parameters. Some film properties can be modified also subsequently.