| 摘要 |
<p>PURPOSE: To prevent dust from adhering to the surface of a mask pattern by a method wherein a glass plate is used in place of a pellicle formed of thin film. CONSTITUTION: A projection light exposure device is composed of a light irradiation section 1, a mask M, a mask stage 2, a projection lens 3, and a work W, wherein a double telecentric lens is used as the projection lens 3, and a glass plate 11 is disposed on the mask stage 2 in parallel with the mask M so as to form a closed space surrounded with the glass plate 11 and the surface of the mask M where a pattern is provided to prevent dust from being attached to the surface of the mask pattern. As a double telecentric lens is made to serve as the projection lens 3, primary light rays pass through the glass plate 11 vertically, so that no optical aberration is induced even if a thick glass plate is used. Another means that gas is made to flow through the closed space or ionized gas is introduced into the closed space to prevent the mask from being charged with electricity is jointly used, whereby dust attached to the surface of a mask pattern is much lessened.</p> |
