Abstract
As the integrated circuit technology evolves to a greater complexity, the purity of process gases becomes a critical issue. It is a major problem to distribute an ultra-high purity gas to the points of use while maintaining the achieved purity as the gas travels through the piping with numerous valves, filters, sensors, bends, etc.; each a potential source of contaminants. Moisture is perhaps the most important homogeneous impurity in ultra-high purity gases used in semiconductor manufacturing. A difficulty associated with moisture is its strong adsorption on various gas distribution surfaces and its slow desorption due to a very high activation energy. In this paper, the mechanism of moisture desorption from both stainless steel and 80% alumina surfaces is studied. A unique experimental setup is designed and utilized to determine desorption under gas flow conditions by monitoring the moisture concentration at the system outlet. A simple analytical technique is presented to analyze the desorption data so acquired, in an effort to normalize the results and thus making them system independent. Desorption rate constants for stainless steel and ceramic (80% alumina) surfaces are calculated using this model at a constant temperature.
Original language | English (US) |
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Pages (from-to) | 507-511 |
Number of pages | 5 |
Journal | IEEE Transactions on Components, Hybrids, and Manufacturing Technology |
Volume | 14 |
Issue number | 3 |
DOIs | |
State | Published - Sep 1991 |
Externally published | Yes |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- General Engineering
- Industrial and Manufacturing Engineering
- Electrical and Electronic Engineering