Wafer transport mechanism

An apparatus for transporting a workpiece through a vacuum housing, said apparatus comprising:

• a sleeve having a hollow interior;
• a first seal mounted on the housing for rotatably receiving the sleeve, whereby the sleeve extends between the interior and exterior of the housing;
• a linking arm enclosure assembly having a hollow interior, said linking arm enclosure assembly being secured at one end to the interior end of the sleeve so that the hollow interior of the sleeve is open to the hollow interior of the linking arm enclosure assembly;
• a workpiece transport arm;
• a secondary seal mounted in the other end of the linking arm enclosure assembly for receiving the workpiece transport arm;
• a shaft mounted coaxially within the hollow interior of the sleeve terminating at one end within the hollow interior of the linking arm enclosure assembly;
• a bearing assembly rotatably mounted on the sleeve and fixedly coupled to the shaft;
• means mounted on the bearing assembly for rotating the sleeve relative to the shaft;
• means mounted on the bearing assembly for rotating the sleeve and shaft relative to the housing;
• and
• means for coupling the workpiece transport arm to the shaft so that rotation of the sleeve relative to the shaft causes the workpiece transport arm to rotate relative to the linking arm.

An apparatus for transporting a workpiece relative to a housing, said apparatus comprising:

• a sleeve mounted to rotate relative to the housing;
• a shaft mounted coaxially within the sleeve;
• a linking arm fixedly attached at one end to the sleeve;
• a workpiece transport arm rotatably secured to the other end of the linking arm;
• a bearing assembly rotatably mounted on the sleeve and fixedly coupled to the shaft;
• a first motor means mounted on the bearing assembly and operatively coupled to the housing;
• a second motor means mounted on the bearing assembly and operatively coupled to the sleeve, whereby the sleeve and shaft may be rotated simultaneously by actuating the first motor means and the sleeve may be rotated independently of the shaft by actuating the second motor means;
• and
• means for coupling the workpiece transport arm to the shaft so that rotation of the sleeve relative to the shaft causes the workpiece transport arm to rotate relative to the linking arm.