Volume 11, No. 4, August 2011, Pages 460-465 PDF(196 KB)
Quantitative Techniques for Measuring Cleanroom Wipers with Respect to Airborne Molecular Contamination
Angus Shiue1, Shih-Cheng Hu2, Chi-Hung Lin3, Shin-In Lin3
1 Graduate Institute of Mechanicaland Electrical Engineering, National Taipei University of Technology, Taipei, Taiwan
2 Department of Energy and Refrigerating Air-conditioning Engineering, National Taipei University of Technology, Taipei, Taiwan
3 Department of Testing and Certification, Taiwan Textile Research Institute, Taipei, Taiwan
Cleanroom wipers are generally of three classifications, namely, synthetic, natural fibers and blends of fibers. Ultra-fine split type fiber is mostly selected as the wiper material since cleanrooms need high filtering efficiency. The three wiper samples selected were made from knitted polyester filament fabric with hot-cut or sealed edges. The wiper samples A and B are considered for the application in Cleanroom Class 10 level environment and wiper sample C is for Cleanroom Class 100 level environment. ASTM E1560-95 and IEST-RP-CC004.3: 2004 are the two standards for testing cleanroom consumables. Following these standards, three specific wipers were compared in terms of residue concentration of liquid particles, ions, metals and non-volatile organic compounds using liquid particle counting (LPC), inductively coupled plasma mass spectrometry (ICP-MS), ion chromatography (IC), and nonvolatile residue (NVR) methods, respectively. All experiments were performed in a cleanroom of Class 100. Detailed test results were very informative to characterize the performance of wipers manufactured by specific processes and materials.
Cleanroom; Wiper; Airborne molecular contamination; Particle; Ion; Nonvolatile residue.