Vertical wafer carrying apparatus

A vertical wafer carrying apparatus comprising:

• a pair of endless belts, each having a plurality of outward projections forming a plurality of substantially horizontal, parallel shelves;
• support means supporting said pair of endless belts is spaced apart relationship with at least some pairs of said projections on said endless belts facing each other for supporting respective semiconductor wafers on said shelves and defining a substantially vertical transfer path having an entrance and an exit between said endless belts, said endless belts being movable along respective endless loops;
• drive means for driving each of said endless belts along the endless loops at substantially equal speeds in the same direction along the vertical transfer path;
• an entrance conveying unit disposed at the entrance of the vertical transfer path for conveying a semiconductor wafer to the entrance;
• an exit conveying unit disposed at the exit of the vertical transfer path for conveying a semiconductor wafer from the exit;
• an entrance sensor for sensing semiconductor wafer at the entrance of the vertical transfer path and actuating said drive means in response;
• and
• an exit sensor for sensing a semiconductor wafer at the exit of the vertical transfer path and actuating the exit conveying unit in response.