Lithographic apparatus and device manufacturing method
First Claim
Patent Images
1. A lithographic apparatus comprising:
- an illumination system to condition a projection beam of radiation;
a support structure to support a patterning device, the patterning device constructed to impart the projection beam with a pattern in its cross-section;
a substrate table to hold a substrate; and
a projection system to project the patterned beam onto a target portion of the substrate;
wherein the patterning device has a critical dimension whose value varies with position across the patterning device,the apparatus further comprising a controller, configured and arranged to vary a radiation dose applied to the target portion according to a position on the target portion based on variation of the critical dimension of the patterning device so as to compensate for the variation of critical dimension.
1 Assignment
0 Petitions
Accused Products
Abstract
A lithographic apparatus comprises an illumination system for providing a projection beam of radiation and a support structure for supporting a patterning device which impart the projection beam with a pattern in its cross-section. The patterning device has a non-flat critical dimension (CD) profile across its width. A projection system projects the patterned beam onto a target portion of a substrate. Dose variation device for varying the radiation dose across the width of the target portion compensates for the non-flat CD profile of the patterning device.
6 Citations
32 Claims
-
1. A lithographic apparatus comprising:
-
an illumination system to condition a projection beam of radiation; a support structure to support a patterning device, the patterning device constructed to impart the projection beam with a pattern in its cross-section; a substrate table to hold a substrate; and a projection system to project the patterned beam onto a target portion of the substrate; wherein the patterning device has a critical dimension whose value varies with position across the patterning device, the apparatus further comprising a controller, configured and arranged to vary a radiation dose applied to the target portion according to a position on the target portion based on variation of the critical dimension of the patterning device so as to compensate for the variation of critical dimension. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A device manufacturing method comprising:
-
providing a projection beam of radiation using an illumination system; using a patterning device to impart the projection beam with a pattern in its cross-section, the patterning device having a critical dimension whose value varies with position across the patterning device; projecting the patterned beam of radiation onto a target portion of a substrate; and varying a radiation dose applied to the target portion according to the position on the target portion based on variation of the critical dimension of the patterning device so as to compensate for the variation of critical dimension. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. A method of forming a patterning device for imparting a projection beam with a pattern in its cross section in a lithographic apparatus, comprising:
-
providing a mask substrate having a radiation blocking film formed thereon; depositing a layer of resist on the radiation blocking film, the thickness of the layer of resist being different at the edge of the film to the center; illuminating the resist with a patterned beam of radiation to impose a pattern thereon; developing the resist to fix the pattern; etching the radiation blocking layer in the form of the pattern; wherein the critical dimension of the pattern etched in the radiation blocking film is different at the edge of the patterning device from that at the center. - View Dependent Claims (22)
-
-
23. A method to correct for a varying critical dimension of a patterning device, the method comprising:
-
providing data regarding critical dimension values of the patterning device, a plurality of the values varying with position across the patterning device; and calculating a radiation dose to be applied to the patterning device so as to compensate for the variation of critical dimension across the patterning device;
the calculated radiation dose being based on the critical dimension values provided;wherein the patterning device is exposed in accordance with the calculated radiation dose. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32)
-
Specification