Characterization and Control of Organic Airborne Contamination in Lithographic Processing

摘要

In the DUV lithographic process, airborne contamination, such as ammonia and 1-methyl-2-pyrrolidinone, is known to present several processing problems. Presently, these airborne contaminants are effectively controlled using either acid-base or ion-exchange chemistry. However, as lithographic processing moves towards the creation of smaller features using 193 nm and 157 nm technologies, airborne and condensable organic contamination presents an ever-increasing concern. In addition, the wide range of chemical and physical properties of the organic contaminants found in the processing environment, do not lend themselves to effective control using the specific chemisorptive techniques currently applied. In conjunction with our efforts to design improved chemical filters for the effective control of organic airborne contaminants, we have attempted to characterize the organic airborne contamination found in the lithographic processing environment. In addition, we have evaluated the effectiveness of activated carbon filters for their removal. In this report, we will present our current findings and reveal some of the benefits and concerns associated with the use of activated carbon-based chemical filters for the control of organic airborne contamination in present and future processing applications.