A system including a plurality of gas flow control units in cabinets which are connected to distribute process gas, on demand, to a plurality of utilization locations known as "tool" locations in a semi-conductor manufacturing plant. Transducers are used in the system to measure pressures and other control...http://www.google.es/patents/US5508947?utm_source=gb-gplus-sharePatente US5508947 - Process gas distribution system and method with automatic transducer zero calibration
Process gas distribution system and method with automatic transducer zero ...
