Outgassing Test for Cleanroom Construction Materials and Polymers

摘要

With increasing integration of semiconductor devices, organic contaminants adhering to silicon wafer surfaces have become a serious problem because they strongly affect production yield and device performance. The cleanroom construction materials and polymers are the major source of organic contaminants in cleanroom. Therefore, outgassing test for cleanroom construction materials and polymers is just as important as the evaluation of organic contaminants in cleanroom air, because it will help us identify the organic contaminant sources and mechanisms of organic contamination. At present, outgassing test method for organic compounds with high boiling-points is to be established because polar organic compounds with high boiling-points tend to adhere to silicon wafter surfaces more strongly than the other organic compounds. We employed five outgassing test methods for cleanroom construction materials and polymers, whcih can be used for mini-environment and wafter carrier boxes, and studied the relationships between the outgassing condition and the outgassing test results. We found that there is a linearity between the logarithm of outgassing amount and the reciprocal of temperature, 1/T. The outgassing amount at an arbitrary temperature can be evaluated with a few data of other temperature by using the linearity.