Inficon SQC-310 User Manual

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PN 074-550-P1C
SQC-310 Operating Manual
7.5 Control Loop
The function of the control loop parameters is to match the SQC-310 reaction to an
error (between the measured deposition rate and the desired rate) to the time
related characteristics of the deposition source and its power supply. There are
three adjustable parameters; P(proportional), I(integral) and D(derivative) used to
accomplish this. It is convenient to think of sources as falling into two categories
"fast" or "slow" (see section 7.5.1). The tuning parameters are affected by source
level, rate, sweep range or beam density, tooling and source condition.
The proportional gain (P-Term) parameter sets the rate at which the control voltage
changes in response to an error signal (see Figure 7-1). Any error in the rate
causes the source control voltage to ramp to a new value. When the source control
voltage increases or decreases to the correct value, the value required to achieve
the desired rate, the error goes to zero and the output remains constant. A higher
value for this term would be a more responsive (but potentially unstable) control
loop.
Figure 7-1 Proportional Gain

Inficon SQC-310 Specifications

General

Brand	Inficon
Model	SQC-310
Category	Controller
Language	English