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Chapter 2 operation – SIGMA SQC-122c User Manual

Page 17

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Chapter 2

Operation

2-3

The PID parameters control the response of the SQC-122c to changes in deposition
rate. These values are unique to each deposition chamber setup, and to a lesser extent
to each material.

The P Term is proportional (or gain), the % process rate change divided by the % input
power change. The I Term (integral) sums the rate deviations over time to more
accurately achieve the rate setpoint. The D Term (derivative) speeds response to
sudden changes in rate. Volumes have been written on determining the proper PID
settings. See the section on Loop Tuning later in this chapter for a common PID loop
tuning procedure. For now, you should probably leave these values at their defaults.

Press Film Conds to enter the film conditioning menu. Film preconditioning is used to
prepare a material for deposition. When the film deposition is complete, post
conditioning ramps power down to an idle level. It may also ramp power to a level
appropriate for wire feeding new material. Refer to the Thin Film Process Overview in
Chapter 1 for an illustration of pre and post conditioning.

Ramp1 Time

Ramp2 Power

Ramp2 Time

Soak2 Time

Feed Power

Ramp Time

Feed Time

Idle Power

Ramp Time

0.950

2.90

0:00:00

10.0

75.0

Out1

O n

O n

0.7

%

h:mm:ss

h:mm:ss

%

h:mm:ss

h:mm:ss

%

h:mm:ss

RATE(A/s)

0.0

Film Conditioning Menu

Exit to

Main

Prev

Menu

Edit

THICKNESS(kA)

0.000

POWER(%)

0.0

My Process 1 Editing: Aluminum

Parameter

Value

Units

Ramp1 Power

50

%

Soak1 Time

0.0

h:mm:ss

h:mm:ss

Set the Ramp 1 Power and Time to values that will slowly bring the material to a near
molten state. Set the Soak 1 Time to a value that will allow the material to
homogeneously achieve the state. Ramp 2 is used to slowly bring the material to a
power level that nearly matches the desired deposition power. Use Soak 2 to hold the
material at that level until deposition (i.e. rate control) begins.

If you use wire feed to replenish material after deposition, set the Feed Power and times
as required. Idle typically ramps output power back toward zero at the end of a
process.