ONTRAK Synergy Integra, Руководство по эксплуатации

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C h a p t e r 4 P R O C E S S D E S C R I P T I O N
7/26/00 INTEGRA Operations Revision A 4-9
20-0200-231 (CR), 20-0200-232 (Std), 20-0200-251 (CD)
In order to maintain optimum cleaning efficiency, the brushes are
periodically cleaned and/or conditioned through processes defined
in three sets of variables provided on the
BRUSH STATION DEFINE
CLEANING SCREEN
. See “Modify Brush Cleaning Options” on page
9-23 and “Process Idle Time” on page 4-6.
Process
Integra’s standard configuration for Brush Station #2 is hydrofluoric
acid* (HF). If Brush Station #2 is set up with the HF chemical
dispense drawer and the Process Recipe for Brush Station #2 is set up
for processing with HF, then for each EVENT in which HF is
activated, dilute HF (0.5 - 1.0 wt.%) flows into the brush core and out
through the permeable brush material. HF etches the damaged oxide
layer and removes contamination from the wafer surfaces.
A
NOTE:
When processing with HF, the DI LOW FLOW must be OFF to prevent
dilution of the chemical. See “Change EVENT Application Of DI LOW FLOW” on page
9-12 for information on changing the DI LOW FLOW status.
During the cleaning cycle, HF dispenses for the period of time set in
each EVENT during which it is activated. (See “Change HF Flow
Option” on page 9-23.) When DI HIGH FLOW activates in an
EVENT, a high volume of DI water injects into the brush core and
out through the permeable brush material. This action flushes the
chemical out of the brushes, returns the pH to the proper level, rinses
loosened contamination out of the brushes, and rinses contamination
off the wafer. Once the pH is raised to its neutral level, the DI HIGH
FLOW valve CLOSES and the DI LOW FLOW valve continues to
remain OPEN (it is a normally open valve) to perform a DI water
cleaning procedure. The wafer continues in the DI water cleaning
process until it transfers to the Spin Station. (See “Change HF Flow
Option” on page 9-23 and “Change EVENT Application Of DI
HIGH FLOW” on page 9-11.)
A
NOTE:
Do not select DI HIGH FLOW and HF at the same time. If both are selected in
the
BRUSH STATION #2 RECIPE
screen, a message is displays stating that only one can
be used.
During the complete cleaning cycle, the brushes continue turning in
opposite directions to exert constant pressure on the wafer, keeping
it firmly pressed against the Brush Station rollers. The continuously
turning rollers rotate the wafer between the brushes. This dual action
of rotating the wafer between the turning brushes creates the
scrubbing action which cleans both surfaces of the wafer.