Abstract: 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 parameters. Zero calibration of the transducers is provided by automatically subjecting each transducer to a reference computer routine to compute the difference between the standard value and the transducer output, and store the difference as an "offset" to correct the output of the transducer. Thus, re-calibration is performed simply and quickly, at a relatively low labor cost and with relatively little downtime for the system.

Abstract: 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 parameters. Zero calibration of the transducers is provided by automatically subjecting each transducer to a reference computer routine to compute the difference between the standard value and the transducer output, and store the difference as an "offset" to correct the output of the transducer. Thus, re-calibration is performed simply and quickly, at a relatively low labor cost and with relatively little downtime for the system.

Abstract: Gas flow control units in cabinet are connected to distribute process gas, on demand, to a plurality of utilization locations known as "tool" locations in a semi-conductor manufacturing plant. The flow control units are adapted to deliver process gas selectively from one of two supply tanks to any one or all of four different tool locations. Simple, fast, low-cost purging of the gas delivery conduits is provided to facilitate maintenance, gas cylinder changes, etc. Means are provided to enable pulse purging of the long gas delivery conduit from the cabinet to the tool when flow-through or other purging is not possible.

Abstract: Gas flow control units in cabinets are connected to distribute process gas, on demand, to a plurality of utilization locations known as "tool" locations in a semi-conductor manufacturing plant. Each gas flow control cabinet has an exhaust duct which connects to an exhaust duct in the plant through which waste gases from the cabinet are exhausted by a fan to the atmosphere. Low flow alarm signals are generated if the exhaust flow is below a desired level. A programmable controller is provided for controlling the alarm function according to the size of the exhaust ducting from the plant so as to facilitate installation and operation of each cabinet in a variety of locations with different duct sizes.

Abstract: A plurality of gas flow control units in cabinets are connected to distribute process gas, on demand, to a plurality of utilization locations known as "tool" locations in a semi-conductor manufacturing plant. Each gas flow control unit is connected to a single tool interface controller over a single communications cable. The status and operational characteristics of the individual units are communicated through the tool interface controller to a supervisory control computer by means of polling. Each flow control cabinet has its own data processor, and can be operated alone. Also, the supervisory computer can be used to operate each cabinet, as well as to monitor operations of the system. Gas demand and other signals are communicated from each tool location to the control units through a single cable connected to the interface controller, thus reducing the original wiring cost.

Abstract: Means are provided for adjustably setting and determining the time duration of flow of a purge gas through process gas supply conduits which supply process gases to semiconductor manufacturing operations. These features are used advantageously to facilitate the changing of certain components of the system, such as a tank of toxic process gas, and/or a filter. A plurality of gas storage and distribution cabinets can be controlled from a single remote personal computer. Alternatively, each individual unit can be controlled by means of its own control system. Setpoints defining, for example, time intervals and pressures to be used in controlling the functions of the gas cabinets may be selected and entered through a front panel on the gas cabinet, or through the remote terminal. A print-out of the selected setpoints is provided by the terminal for improved record keeping of safety procedures used.