Better Process Protection with Automated Gas Monitoring/ Purification

The presence of moisture, oxygen, and other impurities in a process gas stream is highly undesirable. These impurities decrease yields because they form haze and oxides in films, cause dislocation defects by reacting to form particles [1], and increase the corrosiveness of some gases [2, 3]. Impurities in process tools can be a result of poor gas quality, gas distribution leaks, virtual leaks (a trapped contaminant that outgases over time), inadequate purge procedures, and inadvertent system breaches. Process gas purification - whether at the source, in the gas manifold, or at the point of use - is a critical part of preventing impurities from reaching process tools [4]. A smart purifier with the capability to close gas line valves in the event of an impurity intrusion that would exceed a process specification or the purifier's recommended range of operation has been developed by Matheson Tri-Gas. Inputs for the control logic include changes in the purifier bed temperature as well as external signals from on-line analyzers that monitor the concentration of key impurities in the inlet gas stream.