| Monitoring Pressure in Gas Cabinets |
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Semiconductor Manufacturing
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| In semiconductor manufacturing, specialty gasses
are used in the wafer doping process. The gases are
stored in tanks and the delivery system (manifold)
incorporates pressure transmitters to monitor the
gas pressure. This pressure transmitter
communicates to the control system that the proper
pressure is being maintained and delivered. |
APG's sensor incorporates a stainless steel
design that is "One Wetted" - the pressure
sensor surface that is in contact with the gas is
machined from a solid block of stainless steel,
so that the only material that comes into
contact with the corrosive gas is stainless steel.
These one piece port configurations are much
less likely to leak the poisonous and corrosive
gases that are often used. In addition, the port
fittings can be made in various configurations
that can be polished to a 10RA finish. |
| Gas cabinets use Automation Products Group, Inc. pressure transmitters, or
digital pressure gauges to transmit the gas pressure
measurement signal to the controller system which
maintains the proper pressure. Pressure control is
crucial to maintain the proper rate of gas flow in the
wafer doping process. |
| Two-Wire Pressure Transmitter |
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Accuracy (linearity, hysteresis,
repeatability): ±0.25% F.S. (B.F.S.L.) |
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High overpressure capability |
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Hybrid compensation circuit |
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Zero and span adjustments
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| PT-L3, PT-L10,
PT-L1, PG-7 and PG-5000 |
| High Level Output Pressure Transducer |
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Accuracy (linearity, hysteresis,
repeatability): ± 0.25% F.S. (B.F.S.L.) |
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Hybrid compensation circuit for reliability |
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Compact size and very low weight (3 oz.) |
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Zero and span adjustments |
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High overpressure capability |
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True 0-10 VDC, can cross zero (PT-L3 also has
true 0-5 VDC)
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Self-powered by standard 9 V battery |
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Large, full 4 digit display with 0.5 in. characters |
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Keypad operated microprocessor circuit has
"TARE" (auto zero), peak hold and an alarm
standard functions (PG-7) |
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Ranges vacuum to 10,000 psi |
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Direct reading to 9,999 psi |
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±0.25% of full-scale accuracy |
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A 16 minute auto off circuit (4 minute with
backlight) |
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On/off switch with optional auto-off circuit |
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Peak-hold and analog outputs available (PG-5000)
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Backlight (4 minute auto off circuit) |
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Zero adjust via up-down keys
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