Exposure method and electronic device manufacturing method

• US 20090042139A1
• Filed: 02/27/2008
• Published: 02/12/2009
• Est. Priority Date: 04/10/2007
• Status: Abandoned Application

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Shiraishi, Naomasa, Inoue, Hideya
• Application Number:
  US12/071,911
• Publication Number:
  US 20090042139A1
• Time in Patent Office: Days
• US Class Current: 430/311
• CPC Class Codes: G03F 7/70266 Adaptive optics, e.g. deformable optical elements for wavefront control, e.g. for aberration adjustment or correction
• CPC Class Codes: G03F 7/703 Non-planar pattern areas or non-planar masks, e.g. curved masks or substrates
• CPC Class Codes: G03F 7/70425 Imaging strategies, e.g. for increasing throughput or resolution, printing product fields larger than the image field or compensating lithography- or non-lithography errors, e.g. proximity correction, mix-and-match, stitching or double patterning
• CPC Class Codes: G03F 7/70633 Overlay, i.e. relative alignment between patterns printed by separate exposures in different layers, or in the same layer in multiple exposures or stitching
• CPC Class Codes: G03F 7/70783 Handling stress or warp of chucks, masks or workpieces, e.g. to compensate for imaging errors or considerations related to warpage of masks or workpieces due to their own weight
• CPC Class Codes: G03F 9/7003 Alignment type or strategy, e.g. leveling, global alignment
• CPC Class Codes: G03F 9/7084 Position of mark on substrate, i.e. position in (x, y, z) of mark, e.g. buried or resist covered mark, mark on rearside, at the substrate edge, in the circuit area, latent image mark, marks in plural levels
• CPC Class Codes: G03F 9/7088 Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection
• CPC Class Codes: H01L 2223/54453 for use prior to dicing
• CPC Class Codes: H01L 2223/5446 Located in scribe lines
• CPC Class Codes: H01L 2223/5448 Located on chip prior to dicing and remaining on chip after dicing
• CPC Class Codes: H01L 23/544 Marks applied to semiconductor devices or parts, e.g. registration marks, alignment structures, wafer maps test patterns for characterising or monitoring manufacturing processes H01L22/00
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An exposure method enabling deformation occurring in a unit exposure field to be measured rapidly and accurately and enabling a plurality of patterns to be superimposed on a substrate with high accuracy. The exposure method of the present embodiment for exposing a bright-dark pattern on the substrate using a projection optical system includes a position detection process for detecting the positions of a plurality of position detection marks, relative to a substrate-in-plane-direction of the substrate, arranged in at least one functional element in a unit exposure field of the substrate, a deformation calculation process for calculating the state of deformation occurring in the unit exposure field based on information related to the positions of the position detection marks obtained in the position detection process, and a shape modification process for modifying the shape of the bright-dark pattern to be exposed on the substrate based on the deformation state obtained in the deformation calculation process.

Claims

1. An exposure method for exposing a bright-dark pattern onto unit exposure fields of a substrate via a projection optical system, the exposure method comprising:

a position detection step of detecting positions of a plurality of position detection marks in at least one unit exposure field relative to an in-plane direction of the substrate with a position detection system including a plurality of reference detection positions that fall within a range substantially equal to one of the unit exposure fields of the substrate;

a deformation calculation step of calculating a state of deformation in the at least one unit exposure field based on information related to the positions of the plurality of position detection marks obtained in the position detection step; and

a shape modification step of modifying a shape of a bright-dark pattern to be exposed on the substrate based on the deformation state obtained in the deformation calculation step;

wherein the position detection marks to be detected in the position detection step are arranged in at least one functional element included in the at least one unit exposure field on the substrate.

2. The exposure method according to claim 1, wherein the position detection marks arranged in the at least one functional element includes position detection marks arranged in a marginal area of the at least one functional element.

3. The exposure method according to claim 1, wherein the position detection step includes detecting the positions of at least four of the position detection marks.

4. The exposure method according to claim 1, wherein the position detection step detects the positions of the plurality of position detection marks with a plurality of detection optical systems parallel arranged next to one another.

5. The exposure method according to claim 4, wherein the position detection step detects light via the plurality of detection optical systems with a plurality of light detection units.

6. The exposure method according to claim 1, wherein the position detection step detects light via at least one detection optical system included in the position detection system with a plurality of light detection units arranged in a detection range of the detection optical system.

7. The exposure method according to claim 1, wherein the position detection step detects light via a common detection optical system included in the position detection system with a plurality of light detection units parallel arranged next to one another.

8. The exposure method according to claim 7, wherein the position detection step detects the positions of the plurality of position detection marks while moving the substrate relative to the common detection optical system.

9. The exposure method according to claim 1, wherein the position detection step detects the positions of the plurality of position detection marks without using the projection optical system.

10. The exposure method according to claim 1, wherein the shape modification step includes an aberration modification step of modifying aberration of the projection optical system.

11. The exposure method according to claim 10, wherein the aberration modification step includes an optical surface shape modification step of modifying the shape of at least one optical surface in the projection optical system.

12. The exposure method according to claim 11, wherein the optical surface shape modification step modifies the shape of an optical surface arranged at a position near an object plane of the projection optical system, a position optically conjugate to the object plane, a position near the conjugate position, or a position near an image plane of the projection optical system.

13. The exposure method according to claim 1, wherein the shape modification step includes a mask surface shape modification step of modifying the shape of a pattern surface of a mask arranged on an object plane of the projection optical system.

14. The exposure method according to claim 1, wherein the bright-dark pattern is exposed onto the substrate using the projection optical system that has a reduction magnification.

15. The exposure method according to claim 1, further comprising:

a scanning exposure step of scanning and exposing the bright-dark pattern onto the substrate while moving the substrate relative to the projection optical system in a predetermined direction;

wherein the shape modification step modifies the shape of the bright-dark pattern in accordance with relative movement of the substrate during the scanning exposure.

16. A method for manufacturing an electronic device, the method comprising:

a lithography step using the exposure method according to claim 1.

17. The electronic device manufacturing method according to claim 16, further comprising:

a mark formation step of forming a plurality of position detection marks in a functional element included in a unit exposure field of a substrate.