Device for adjusting the illumination dose on a photosensitive layer
View Patent ↗A device for adjusting the illumination dose on a photosensitive layer in a microlithographic projection exposure apparatus has a plurality of stop elements which are, in a direction perpendicularly to a scanning direction of the apparatus, arranged next to one another. Each stop element has an outer surface that absorbs substantially all projection light impinging thereon, and a substantially rectangular circumference. Each stop element furthermore has at least one recess in its circumference or at least one opening through which projection light is allowed to pass. A drive unit individually displaces the stop elements along the scanning direction into a light field.
1. An illumination system of a microlithographic projection exposure apparatus, comprising:
a) an optical axis,
b) illumination setting means capable of modifying the angular distribution of projection light in a reticle plane,
c) an illumination dose adjustment device for adjusting the illumination dose on a photosensitive layer to be exposed, said illumination dose adjustment device comprising
a plurality of stop elements which are, in a direction perpendicularly to a scanning direction of the microlithographic exposure apparatus, arranged next to one another, and
a drive unit for displacing the stop elements individually along the scanning direction into a light field,
d) a manipulator for displacing the illumination dose adjustment device along the optical axis,
wherein the manipulator is configured to automatically displace the illumination dose adjustment device along the optical axis if the illumination setting means modifies the angular distribution.
2. An illumination system of a microlithographic projection exposure apparatus, comprising:
a) an optical axis,
b) illumination setting means capable of modifying the angular distribution of projection light in a reticle plane,
c) an illumination dose adjustment device for adjusting the illumination dose on a photosensitive layer to be exposed, said illumination dose adjustment device comprising
a plurality of stop elements which are, in a direction perpendicularly to a scanning direction of the microlithographic exposure apparatus, arranged next to one another, and
a drive unit for displacing the stop elements individually along the scanning direction into a light field,
d) a manipulator for displacing the illumination dose adjustment device along the optical axis, and
e) a control unit that is connected to the illumination setting means and the manipulator and determines the axial position of the illumination dose adjustment device depending on the desired angular distribution,
wherein the manipulator is configured to automatically displace the illumination dose adjustment device along the optical axis if the illumination setting means modifies the angular distribution.
3. An illumination system of a microlithographic projection exposure apparatus, comprising:
a) an optical axis,
b) illumination setting means capable of modifying the angular distribution of projection light in a reticle plane,
c) an illumination dose adjustment device for adjusting the illumination dose on a photosensitive layer to be exposed, said illumination dose adjustment device comprising
a plurality of stop elements which are, in a direction perpendicularly to a scanning direction of the microlithographic exposure apparatus, arranged next to one another, and
a drive unit for displacing the stop elements individually along the scanning direction into a light field,
d) a manipulator for displacing the illumination dose adjustment device along the optical axis,
wherein:
the manipulator is configured to automatically displace the illumination dose adjustment device along the optical axis if the illumination setting means modifies the angular distribution;
each of the plurality of stop elements is an integral and unitary member; each of the plurality of stop elements has a first region adjacent a first end of the stop element, and a second region adjacent a second end of the stop element;
the first region of each of the plurality of stop elements absorbs substantially all projection light impinging thereon; and
the second region of each of the plurality of stop elements has at least one recess, or the second region of each of the plurality of stop elements at least one opening therein.