Ultra-Pure Air (UPA) System Research for Nano-Processing Environments

• Main Authors: Tzu-Sou Chuang, 莊子壽
• Other Authors: Luh-Maan Chang
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/07147424098297745300

博士 === 國立臺灣大學 === 土木工程學研究所 === 101 === As semiconductor processes advance into the nano-technology era, Airborne Molecular Contamination (AMC) has become a major problem in nano-technology development and manufacturing facilities. To deal with this problem, a prototype Ultra-Pure Air (UPA) system with a targeted air quality impurity level of 10 ppt was experimentally developed. The prototype UPA system presently comprises two process modules; pre-treatment and post-treatment. In order to deal with hard-to-remove organic molecular substances within the air, UV185+254nm is used in the pre-treatment module to provide the energy required to reduce the molecules into broken-up pieces of transitional compounds. Aerosol water droplets are introduced at the same time, combining with transitional compounds to form hydrophilic substances. After the “immersing photochemical oxidation” reaction, the hydrophilic contaminants go through the compression and condensation processes which make up the post-treatment module. During the air compression and condensation processes, the collision probability of the aerosols is highly increased between the contaminants and water droplets. Later, a dehumidification process removes the water droplets from within the condensed air; at this point, the contaminants have dissolved in the water and so they are removed at the same time. These pre-treatment and post-treatment processes yield air quality levels of less than 1 ppb of volatile organic compound, the minimum detection limit for a measuring analyzer.