Belichtungsverfahren.

摘要

A method of exposing a wafer to exposure energy such as ultraviolet rays or X-rays through a mask to transfer a pattern of the mask onto the wafer, for example. The temperature of the mask and/or the wafer increases during the exposure operation by absorption of the exposure energy. During the wafer being exposed, the temperature of the mask and/or the wafer is detected. If the temperature is going to exceed the exposable temperature range determined on the basis of the line width of the pattern to be transferred, the exposure operation is interrupted. Then, the heat accumulated in the mask and/or the wafer is removed. Thereafter, the exposure operation is resumed. This is repeated until the predetermined or required amount of exposure is reached, for one shot. By this, the thermal expansion of the mask and the wafer during the exposure operation is prevented to assure the precision of the pattern transfer.