Verification on performance of super nano-cleanroom Part 2. Properties of gas emission from constituent materials for a cleanroom under ultra low humidity condition

摘要

Based on actual measurements in our own developed Super Nano-Cleanroom (floor area: 47 m~2), a comparison between 0 percent and 45 percent relative humidities revealed a slight difference in concentration of both gaseous organic compounds and ionic constituents in the air. This study examined and evaluated changes in the emission rate of outgases from some of the constitute materials for a clean room, which may occur depending on humidity conditions. Results showed no significant differences in emission rates of gaseous organic compounds and Cl~- at between 0 percent and 45 percent relative humidity. However, ammonia showed a tendency to have a slightly lower emission rate at 0 percent relative humidity than that at 45 percent. This is considered to be derived from less moisture being absorbed onto the surface of materials, resulting in a reduced transfer rate of ammonia from inside the material to the material surface.