INFICON MDC-360 Thin Film Deposition Controller - Manual (Page 44)

MDC-360 DEPOSITION CONTROLLER
4-12 PROGRAMMING AND CONTROLLER SETUP
4.2.7.2 AUTOMATIC CRYSTAL SWITCHING
To enable automatic Crystal switching upon failure, set the Crystal Fail paramete
to Switch then set the Backup Sensor, Backup Tooling and Backup Crystal
parameters to define the backup sensor and crystal.
4.2.7.3 RATE ESTABLISH
r
The rate establish feature is used in critical processes where it is important to
position rate prior to opening the source shutter and
e Rate Establish Time parameter sets the maximum time that the
meet within the allotted
ill be
closing
amp
ramps are disabled by default with the Ramp Start and Ramp Stop
Thicknesses set to 999.9.
rystal life
To enable the rate sample feature, set the Sample Dwell% parameter to the
the controller to sample the rate. Then set the
4.2.
trigger an attention sound,
d alarm sounds are
d and
establish the correct de
depositing on the substrates. To use this feature, the sensor head must be
mounted in such a way that it is in the material vapor stream with the source
shutter either opened or closed.
To enable this feature you must set the Rate Estab. Time and Rate Estab. Error
parameters. Th
controller will attempt to keep the rate error within the Rate Estab. Error limit for
a period of five seconds. If the rate error condition is
time then the controller will enter the deposit state. If not, then the process w
halted and a Rate Establish Error will be displayed.
4.2.7.4 RATE RAMPS
Rate ramping is typically used at the beginning of the deposition to ease the rate
up slowly to prevent material spitting. Rate ramping is also used towards the end
of the deposition to achieve a more accurate endpoint thickness. By slowing
down the rate, the thickness overshoot caused by the delay of the shutter
is diminished
The MDC-360 has four rate ramps available. A rate ramp is defined by its R
Start and Ramp Stop Thicknesses and the final rate.
The rate
4.2.7.5 RATE SAMPLE MODE
Rate sample feature is designed for large deposition thicknesses where c
is a problem. . By sampling the rate periodically to maintain rate control, then
closing the sensor shutter with the rate and power level constant, a large
deposition thickness can be achieved with one crystal.
percentage of time you wish
Sample Period parameter to the time period of the sample and not sampling
period.
7.6 RATE DEVIATION ALARM
The MDC-360 provides three rate deviation levels to
an alarm sound, or a process abort. The attention an
momentarily triggered meaning they will sound when the error is exceede