THIN PLATE FLATTENING EQUIPMENT

摘要

PURPOSE:To improve an accuracy of flattening without lowering a through put by a method wherein uneveness and its magnitude of the surface of a thin plate are calculated and the thin plate is changed in the thickness direction according to the calculated value and is flattened. CONSTITUTION:A wafer 4 is drawn out from a cartridge 17 by a transfer means 18 and is transferred onto an absorbing means 20. Then the flatness of the wafer 4 is measured by a flatness measuring means and the uneveness and its magnitude of the surface of the wafer 4 are calculated according to those measured data. This calculated value is transmitted to a control means 23 and the control means 23 controls a wafer deforming means 21, so that the wafer 4 is slightly displaced in the thickness direction and its surface is flattened. When the wafer 4 is flattened a carriage 19 is moved and a pattern of a mask 1 is imaged and printed on the wafer 4 by an optical exposure system 24.