ONTRAK Synergy Integra, Operation Manual, Page: 123 / 350

C h a p t e r 6 S T A R T- U P A F T E R E M O & WA F E R R E C O V E R Y
7/26/00 INTEGRA Operations Revision A 6-5
20-0200-231 (CR), 20-0200-232 (Std), 20-0200-251 (CD)
WAFER RECOVERY
Introduction
The purpose of the wafer recovery procedure is to complete the
processing of all wafers left in Integra processing stations after the
system is prematurely shut down or detects a “Lost Wafer.” Using
this procedure, the wafers can be processed out of the system
without physically touching a wafer’s surface.
Wafer recovery is usually associated with an emergency or premature
process shutdown. In many cases, especially those in which the
processing atmosphere was compromised, recovered wafers should
be run through the complete process again to ensure that they are
properly cleaned. The Wafer Recovery causes the system to ignore
certain sensor inputs and process wafers starting from the wafer
locations, as designated by the operator (usually the wafer in the Spin
Station). The system begins wafer recovery in the Spin Station. No
wafer is allowed to enter the Input Station during Wafer Recovery.
C
HEMICAL
D
ISPENSE
D
URING
W
AFER
R
ECOVERY
If a lost wafer is to be recovered from a Brush Station currently using
HF during processing, HF will not be dispensed during the recovery
process
in that station . All other station processes will be completed
according to the current Process Recipe. This means that a recovery
wafer entering Brush Station #2 from Brush Station #1, when HF is
being used in Brush Station #2, will be processed with HF.
L
OST
W
AFER
Integra’s CPU tracks wafers through the system. If a wafer does not
register in a station when expected, or if it is in a station where it is
not expected, the CPU generates a “lost wafer” error. Lost wafers
occur because there is a power failure, a mechanical malfunction, a
sensor failure, or after an emergency machine shutdown (EMO).
Numerous sensors are positioned to detect the presence of a wafer as
the wafer travels through the system. The most common situations
which can trigger a “Lost Wafer” alarm are:
1 If a wafer arrives in a position that is not currently recognized by
the CPU as waiting for a wafer , a “Lost Wafer” alarm is posted.
2 If a sensor falsely detects a wafer in a station, the system will
register an alarm when the next station fails to detect the wafer
after the proper transfer time has elapsed. The system will continue
trying to detect the wafer until the system is manually halted.