| 摘要 |
PURPOSE:To shorten the main positioning time of a semiconductor wafer and to automate the main positioning by improving the preliminary positioning accuracy of the wafer. CONSTITUTION:Rotating means 24 of a wafer 3 is formed of a concentric semicircular groove group formed at both sides of the center on the surfaces 21A, 21B of a state 21 for supporting the semiconductor wafer 3. A plurality of semicircular grooves 25 of the semicircular groove group 24a, 24b communicate through coupling groove 26 with one another to evacuate in vacuum at the symmetrical positions of the groups 24a, 24b or form air ports 27, 28 for injecting airs. The stage 21 is tiltably composed at an inclining angle of 3-5 deg. at the positioning means 32 side. The means 32 has three positioning pins 30a-30c, the two pins 30a, 30b being contacted with the orientation flat portion 4 of the wafer 3 and the other one pin 30c being contacted with the periphery. |
