"Effect of Contamination from a Gas Delivery System on Gate Oxide Film Defects," Proceedings of Contamination-Free Manufacturing (CFM) and Control for Semiconductor Manufacturing, SEMICON Southwest 96, Austin TX, October 1996.
Abstract: With the advent of 300 mm wafers and 0.25 mm device size, it has become critically important to eliminate microcontaminants in all aspects of wafer processing. For example, for geometries below 0.25 µm, particle killer defect sizes are smaller than 0.01 µm which is the current limit for particle size detection on wafer surfaces. The extent of contamination from gas delivery systems to process gases and the processing environment has been previously reported. This paper discusses the effect of the contamination from a gas delivery system on the quality of the gate oxide film grown using the system. Functionally identical gas delivery systems are compared for contamination contribution to the process gas. The two systems are constructed of different grade materials and components and are termed as conventional and ultraclean gas panels. Gas phase impurity levels and particle shedding from the systems are measured using an atmospheric pressure ionization mass spectrometer (APIMS) and a condensation nucleus counter (CNC). After characterization of the gas delivery systems, gate oxide films are grown using a split lot of wafers in the conventional and ultraclean panels as part of short loop experiments. The gate oxide films are characterized for chemical and electrical properties. |
