| 摘要 |
PURPOSE:To prevent a wafer from being unfocused and its pattern from being deformed at the time of direct exposure to a beam by forming a film having a stronger stress than that of the front surface of a wafer, on the rear surface of the wafer, to alter the warpage of the front surface from a convex one to a concave one. CONSTITUTION:A TiW film 2 having 500-1500Angstrom of thickness is formed on a substrate 1 having flat or convex warpage of several mum height, and an aluminum alloy film 3 is formed 7000-10000Angstrom thereon. At this time, a wafer is warped to form a convex of 20-30mum height. Then, when an Si nitride film 4 is deposited 2mum thick on the rear surface of the wafer, the wafer is warped to form a concave of 10-20mum depth. Subsequently, a resist film 5 is coated 1mum thick on the film 3, and the wafer is mounted in a cassette 6. A focus and a beam current are eventually set by using an alignment mark 9 to expose the wafer.
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