Operations and Maintenance Manual Machine Setup
Version 1.2 - June 2004 9 - 7
GRINDING SEQUENCE
The 7AF grinding sequence for both coarse and fine grind is divided into the segments
shown below. Five segments (grinding step 1, grinding step 2, grinding step 3, dwell,
and lift) are programmable at the Wafer Recipes menu.
Grind
Sequence
Segment
Description
Home
Travel
Height
Rapid Feed
The grind wheel is initially in its home position,
which is at the upper limit switch, a minimum
of 6 mm above the chuck surface.
When the grind cycle starts, the wheel is
rapidly fed to a travel height, which is 2000
microns above the tallest chuck. This is the
height at which the grind wheels are located as
the bridge travels to each of its three positions.
When the bridge is in position, the wheel is
rapidly fed to a height equal to the measured
wafer thickness plus a pre-determined "air cut"
depth.
Note: The air cut depth provides a margin of
error to prevent rapid feeding down to the
wafer surface itself.
To Next Page
Loading...
