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