Journal of the Electrochemical Society, Vol.141, No.2, 566-571, 1994
High-Selectivity and High-Deposition Rate Tungsten CVD Freed from Chamber Cleaning
A chemical vapor deposition method for tungsten films using a chamber with a cold susceptor is proposed for attaining excellent selectivity and a cleaning-free process. High-rate selective deposition above 1.0 mum/min using the reduction Of tungsten hexafluoride by silane is achieved at a substrate temperature of 210-degrees-C by using a cold susceptor chilled by water at room temperature. No deposition of tungsten or by-products on the susceptor surface and the inner surface of the chamber is observed, indicating that the newly developed system is free from cleaning. The deposited tungsten film has the alpha-type structure. The lattice constant of the tungsten is changed by the deposition temperature and the flow ratio of silane to tungsten hexafluoride.