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SC20FAST Magnetic Field Cancelling System |
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Advanced Magnetic Field Cancelling Solutions |
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SC20FAST Product Description
The SC20FAST is a new version of our established
SC20 field cancelling system that has been optimised to cancel the high
frequency fields, typically at 9kHz, from robotic wafer transports in 300mm wafer fabs.
These fields limit the performance of electron beam tools in the fab and are a barrier to
achieving the next semiconductor device CD node.
Where there are also bad DC fields, an
SC20/DCMR sensor can be
added to the system. The outputs from the AC and DC
sensors are combined with a 25Hz crossover frequency in a small adapter box that plugs into
the back of the control unit. When the DC sensor is added, the cancelling
factor is increased at low frequencies. The cancelling factor at 9kHz is unchanged.
The SC20FAST also works with the
remote monitor designed for the standard SC20
to remotely monitor the status and measure field levels.
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COORDINATE SYSTEM
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X, Y, Z rectangular Cartesian |
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UNITS
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Gauss, Tesla (switchable) |
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FIELD CANCELLING
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1. |
SC20FAST/AC
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Components cancelled
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X, Y, Z field components |
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Dynamic range (X, Y & Z)
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20 mG (2 µT) pk-pk |
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Field reduction ratio
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25 X (typical) at 50/60 Hz |
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12 X (typical) at 9 kHz |
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Bandwidth
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1.0 Hz - 60 kHz |
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Sensor 1/f noise limit (0.05 to 1 Hz)
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< 50 µG (5 nT) pk-pk |
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Sensor spot noise (at 50 Hz)
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0.1 µG/√Hz (10 pT/√Hz) |
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DC overload recovery time
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< 2 s |
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2. |
SC20FAST/DC
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Ambient DC field
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± 2 G (± 200 µT) max |
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Dynamic range (X, Y & Z)
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± 10 mG (± 1 µT) incremental |
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Field reduction ratio
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>50 X, DC to 1 kHz |
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12 X (typical) at 9 kHz |
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Bandwidth
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DC - 60 kHz |
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Drift (@23°C ±2°C, 2 hour warm-up)
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DC drift/24 hours < 20 µG (2 nT)
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ULF noise (0.0001 - 0.01 Hz)
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5 µG (0.5 nT) pk-pk (typical)
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Sensor spot noise (at 50 Hz)
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0.1 µG/√Hz (10 pT/√Hz)
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FIELD MEASUREMENT
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Types
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Real time field |
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AC - true RMS amplitude |
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Incremental DC (with DC sensor) |
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Display
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RMS & DC
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3.5 digit LED panel meters |
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Sensor dynamic range
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24 mG pk-pk |
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Meter range (reading)Note 1
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0-19.99 mG (1.999 µT) RMS |
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± 19.99 mG (1.999 µT) DC |
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AccuracyNote 2
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± 1.0 % of reading ± 10 µG (1 nT) |
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(DCMR sensor after 2 hours warmup) |
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X, Y, Z real time field outputs
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Scaling
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1.0 V/mG |
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Range
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>± 12 Volts |
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Source resistance
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1 kΩ (avoid shorting) |
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Connectors
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3 X BNC |
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Bandwidth
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25 Hz - 200 kHz (AC sensor) |
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DC - 200 kHz (AC + DC sensor) |
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Trip (AC & DC)
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range of adjustment
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0 - 2.0 mG (200 nT) |
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POWER
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120/240 V 50/60 Hz, 100 VA |
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Note 1:
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RMS & DC measurement ranges are limited by sensor dynamic range |
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Note 2:
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sensors are calibrated with 50 Hz, 10mG RMS square wave field. |
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