Epitaxial enhancement

Epitaxial Enhancement. Epitaxial enhancement is used to deposit a layer of ultrapure silicon on the surface of the wafer. This provides a layer with different properties from those of the underlying wafer material, an essential feature for the proper functioning of the MOS (metal-oxide-semiconductor) transistors that are used in modern chips. In this process, polished wafers are placed into a programmable oven and spun in an atmosphere of trichlo-rosilane gas. Decomposition of the trichlorosilane... 

This reaction was also used to deposit epitaxial silicon at the temperature range of 1000-1040°C, but the deposit was generally unsatisfactory and the reaction is no longer used for that purpose. However, if the reaction is enhanced with a plasma using electron cyclotron resonance (ECR), fluxes may be independently controlled and high-quality epitaxial silicon deposits are obtained at temperatures below 500°C.P 1... 

Reif, R., Low Temperature Silicon Epitaxy by Plasma Enhanced CVD, Proc. 5th European Conf. on CVD, (J. Carlsson and J. Lindstrom, eds.), pp. 13-19, Univ. ofUppsala, Sweden (1985)... 

Zou S, Weaver MJ (1999) Surface-enhanced Raman spectroscopy of cadmium sulfide/cadmium selenide superlattices formed on gold by electrochemical atomic-layer epitaxy. Chem Phys Lett 312 101-107... 

Epitaxial Silicon Wafers using Plasma-Enhanced, Chemical-V apor-Deposition... 

Epitaxial Silicon Wafers using Plasma-enhanced Chemical-Vapor-Deposition 291... 

For epitaxial silicon wafers, product design focuses on optimizing the geometry of the plasma-enhanced, chemical-vapor-deposition (PECVD) reactor. To increase productivity, and maintain acceptable thickness uniformity, on the order of 5%, a simple optimization strategy locates a design that completes the deposition in 62 s. Then, for a standard manufacturing process, the economics are driven by the wafer costs, which are provided by a vendor at 206/wafer. At a sales price of 260/epitaxial wafer, the investor s rate of return is 18.3% and the return on investment is 25.3%. 

D. A. Brass and A. G. Lee, The Production of Epitaxial Silicon Wafers via Plasma Enhanced Chemical Vaposition, Univ. Pennsylvania, Towne Library, 2003. 

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