a set of adjacent processing stations 91 94 to transfer wafers 78 around in a clockwise moving queue each of the processing stations 91 94 respectively comprises a bottom 95 98 and a top 99 102 a handling chamber bottom 104 and a lid 105 provide a vacuum seal for the circular wafer handling chamber 88 a set of four cylindrical metal sleeves 106 109 each with top and bottom o ring seals raise and lower independently or in unison to seal each respective area for process stations 91 94 from the handling chamber bottom 104 to the lid 105 fig2 a shows the cylindrical metal sleeves 106 and 109 in their lowered position and the cylindrical metal sleeves 107 and 108 in their raised and sealed position the cylindrical metal sleeves 106 109 are lowered to allow the transfer of wafers 78 between the processing stations 91 94 the cylindrical metal sleeves 106 109 are raised and sealed to allow the wafers 78 to be exposed through a corresponding port 111 114 to a particular removable process modules 99 102 for example the process modules 99 102 may comprise conventional semiconductor process reactors for photo resist removal cleaning plasma etching sputtering vapor deposition etc the system 70 comprises a processed wafer elevator chamber 126 with a vacuum seal door 128 for outputting a cassette 130 of processed semiconductor wafers 132 an elevator drive 134 raises and lowers an elevator platform 136 to select a spot for a particular processed wafer 132 transferred out by a double axis arm 136 in an anteroom chamber 138 fig2 c shows the transfer carousel 90 in the act of wafer transfer unprocessed wafers 78 are shown transferring clockwise between the four process stations 91 94 and are output as processed wafers 132.