High-speed and sensitive multiple-point ammonia gas monitor system

In order to get a precise pattern control in a chemically amplified photo-resist process, the high performance multi-point ammonia gas monitor was developed. A single point high speed and sensitive ammonia monitor was reported in ISSM'96. This system has expanded its ability by adding 16 measurement ports, 4 diffusion scrubbers, and one analyzer. As a result, it provided the capability of measuring 9 sampling data for each point per day. Its sensitivity is sub /spl mu/g/m/sup 3/ which is enough to watch, for example to detect the change of people in a clean-room, and it is able to monitor 40 meters away in radius. This system is already in a field test, and it shows a good performance for daily watch of our new research and development line.