The wafer transfer device has a first unit with a plurality of first slots for receiving {HEAD ~ a first group} of semiconductor wafers and a second unit with a plurality of {TAIL ~ slots} for receiving a second group of semiconductor wafers 
The wafer transfer device has a first unit with a plurality of first slots for receiving { HEAD ~ a first group } of semiconductor wafers and a second unit with a plurality of { TAIL ~ slots } for receiving a second group of semiconductor wafers
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH