V-TEK Royce DE35-ST, User Manual

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76 D292469I
Adjusting Die Pickup Tip Force
The die Pickup Head is supported by two flat Cantilever Springs. The Cantilevers ensure
that the Pickup Head can move up and down without any side-to-side "play" or
backlash. This is essential when handling small die. The Cantilevers also provide a way
to adjust the pickup force that is imposed on the die during the die ejection process.
This can be very important when working with fragile semiconductor structures. Pick up
forces as low as 7g. may be used repeatedly.
The
TOUCH DOWN
force is set at 7 to 10 grams during machine setup when the head is
at its lower height limit. This force is what is required to break an electrical contact of
the Cantilevers with the Z-Arm. When this electrical contact is broken, the LCD display
will indicate the PICKUP IN CONTACT . This force will be altered by the pickup height:
the higher above the lower limit, the higher the force necessary to indicate PICKUP IN
CONTACT . The height of the Die Eject Head should be set as low as possible while
making contact with the Pickup Tip in the Pick Position .
1. Press SINGLE STEP .
2. Lower the Eject Head all the way down, using the thumbscrew(DE35-
ST) /screw (DE35-300) on the right of the DES Eject Head support.
3. Cycle the system until the Z-Arm is in the Pick Position at Pick height, LCD will
indicate TURN ON PICKUP VACUUM and PICKUP CLEAR .
4. Use the DES Height Adjusting Screw to slowly raise the Eject Head until the LCD
displays PICKUP IN CONTACT .
5. Press the COARSE/FINE key until FINE is displayed on the LCD.
6. Use the UP key to raise the pickup arm until the LCD indicates PICKUP
CLEAR .
7. Raise the needles by pressing the EJECT TEST key. The message
PICKUP IN CONTACT will show in the top right of the display.
8. Contact indicates the tip is touching the die. The needles should raise
the die high enough to touch the tip and allow the tape to release. Needle
height should not be excessive. Raising the die higher than necessary will only
increase the load on the die, possibly damaging the die.
If Needle height needs adjusting, press
EJECT TEST to lower the
needles and adjust the Stop Ring on the Eject Actuator to adjust the
needles. Raise the needles again and recheck as above.
As the ejection proceeds, the needles will push the die up and further increase the
deflection of the Cantilever. The maximum force that the die will be exposed to will
occur at the end of the die ejection process.
• Raising the Pickup by one fine step increases the pickup load by about 2.0 gm
and lifts the Pickup by about 1.25 mil.