Quartz-crystal microbalance study for characterizing atomic oxygen in plasma ash tools

• DOI: 10.1116/1.1335681
• Publication Date: 2002-07-27T09:17:34Z
• Authors: A. K. Srivastava; P. Sakthivel
• Keywords: Quartz Crystal Microbalance; Crystal (programming language); Deposition

This article discusses the measurement of atomic oxygen (AO) concentrations in an discharge using a quartz-crystal microbalance (QCM). is device that has been previously used for monitoring thin-film deposition, among several other applications. The sensor consists silver-coated quartz crystal oscillates at its specific resonant frequency (typically, about 6 MHz), which dependent on mass crystal. When exposed to AO, silver oxidizes rapidly, resulting change mass, and consequent this frequency. measured with counter, when plotted versus time, it may be fit standard diffusion-limited oxide-growth model. model then determine AO flux crystal, by inference, wafer. Initial results QCM measurements FusionGemini Plasma Asher (GPL™-standard downstream microwave asher) Enhanced Strip (GES™-fluorine compatible enhanced strip are presented article. indicate densities order 1012 cm−3 There marked increase concentration addition nitrogen into plasma, decrease increasing pressure constant flow. Effects total plasma volume tool production discussed.