| 摘要 |
PURPOSE:To make it possible to directly measure the thickness of each wafer in a carrier without moving the upper lapping surface plate up and down, by such constitution that a portion of each wafer which moves in a planetary manner on the surface of a lapping surface plate projects from the lapping surface plate. CONSTITUTION:For example, carriers 4 on the lower lapping surface plate of a 4- way lapping machine move in a planetary manner through a sun gear 2 and an internal gear 3. When the lapping of wafers 5 in the carriers 4 has properly progressed and one of the carriers 4 reaches a measuring position 7, the movement is stopped and changed over so that the carrier 4 rotates on its own axis. A hole 9 provided in the carrier is detected by using a photosensor, and the rotation 8 is stopped at such a position that a wafer 5 projects from the surface plate 1. A moving arm 13 is moved 14 and inserted into the measuring position. Then, both sides of the wafer 5 are washed by using the water jetting out from a washing nozzle 12 and air, and the thickness of the wafer 5 is measured by using measuring gauge 1. Accordingly, the thickness of each wafer 5 in the carrier 4 can be directly measured without moving the upper lapping surface plate vertically. |
