Wafer Auto Load Lifter
Original Publication Date: 1988-Oct-01
Included in the Prior Art Database: 2005-Feb-15
A new design for a lifter in a semiconductor wafer auto load system improves the tool's reliability and reduces wafer breakage during operation. The development utilizes a pressurized and vacuum-deflected bellows, cycling the load lifter in synchronization with the control software. The assembly includes a metal bellows 1 with double-stroke action which is positioned by air pressure and vacuum applied to an entry port 2. A sleeve 3 protects the bellows. A sealed chamber 4 within the lifter assembly body has a vacuum applied through port 5 so as to hold the wafer against the wafer cup 6. An ON-OFF port 7 closes when the lifter is in a down position to cut off the vacuum supply. A positive stop 8 controls the limit of travel in the upper position. Appropriate elastomeric seals 9 prevent leaks while the lifter is in operation.