METHOD FOR IMPROVING ALIGNMENT RATE BY CORRECTING THERMAL DIFFERENCE BETWEEN ELECTRON BEAM ROOM AND EXPOSURE CHAMBER

摘要

PURPOSE: A method for improving an alignment rate by correcting a thermal difference between an electron beam room and an exposure chamber is provided to compensate alignment errors according to a thermal difference by using a white crown mask. CONSTITUTION: A method for improving an alignment rate by correcting a thermal difference between an electron beam room and an exposure chamber comprises the following steps. A white crown material is formed on a lower substrate. A white crown mask is formed by patterning a multitude of measuring location for measuring thermal variance of the substrate. The white crown mask is reserved in an electron beam room during a predetermined time. The white crown mask is inserted into an exposure chamber. A varied sized of the white crown mask is measured according to a predetermined interval within the exposure chamber. A difference between a maximum value and a minimum value of the measured data is obtained. A thermal difference between the electron beam room and the exposure chamber is obtained by using the difference. The exposure chamber is compensated according to the thermal difference.