Moving exposure system and method for maskless lithography system

• US 6,379,867 B1
• Filed: 01/10/2000
• Issued: 04/30/2002
• Est. Priority Date: 01/10/2000
• Status: Expired due to Term

• Current Assignee: Disco Corporation
• Original Assignee: Ball Semiconductor, Inc.
• Inventors: Mei, Wenhui, Ishikawa, Akira, Kanatake, Takashi
• Primary Examiner(s): Huff, Mark F.
• Assistant Examiner(s): CHACKO DAVIS, DABORAH
• Application Number:
  US09/480,796
• Time in Patent Office: 841 Days
• Field of Search: 430/296, 430/5, 430/396, 430/397, 430/30, 430/311, 355/53, 355/67
• US Class Current: 430/296
• CPC Class Codes: G03F 7/70275 Multiple projection paths, e.g. array of projection systems, microlens projection systems or tandem projection systems
• CPC Class Codes: G03F 7/70291 Addressable masks, e.g. spatial light modulators [SLMs], digital micro-mirror devices [DMDs] or liquid crystal display [LCD] patterning devices
• 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

Abstract

A photolithography system and method for providing a mask image to a subject such as a wafer is provided. The mask images are divided into sub-patterns and sequentially provided to a pixel panel, such as a deformable mirror device or a liquid crystal display. The pixel panel converts each sub-pattern into a plurality of pixel elements. Each of the pixel elements is then simultaneously focused to discrete, non-contiguous portions of the subject through a microlense array. The subject and pixel elements are then moved (e.g., one or both may be moved) and the next sub-pattern in the sequence is provided to the pixel panel. As a result, light can be projected on the subject, according to the pixel elements, to create a contiguous image on the subject.

Claims

1. A method for projecting a pixel-mask pattern onto a subject, the method comprising the steps of:

dividing the subject into a plurality of sites, with each site comprising a plurality of groups of pixel-sites;

dividing the pixel-mask pattern into a plurality of sub-patterns, each sub-pattern being directed to a specific group of pixel-sites in the plurality of sites;

providing one of the sub-patterns to a pixel panel for creating a plurality of pixel elements by selectively manipulating the pixel panel responsive to the provided sub-pattern;

simultaneously focusing the plurality of pixel elements to discrete, non-contiguous pixel sites;

simultaneously moving the plurality of pixel elements relative to the subject; and

providing a next one of the sub-patterns to the pixel panel responsive to the movement and responsive to the pixel-mask pattern, so that a first pixel site of a group receives a first value and a second pixel site of the same group receives a second value different from the first value.

2. The method of claim 1 further comprising:

projecting light incident to the pixel panel.

3. The method of claim 1 wherein the pixel panel is a liquid crystal display, and the step of creating a plurality of pixel elements includes selectively manipulating the liquid crystal display responsive to the provided sub-pattern.

4. The method of claim 1 further comprising:

removing diffracted light from each of the pixel elements by passing the pixel elements through a grating.

5. The method of claim 1 wherein the step of moving utilizes a vibrator.

6. The method of claim 5 further comprising:

mechanically linking the vibrator to the subject.

7. The method of claim 1 wherein the step of focusing simultaneously creates a plurality of coplanar focal points on the subject.

8. The method of claim 1 further comprising:

aligning the pixel-mask pattern with the subject prior to providing a sub-pattern to the pixel panel.

9. The method of claim 1 wherein the discrete, non-contiguous pixel-sites of the subject are hexagonal in shape.

10. The method of claim 1 wherein the step of providing the sub-patterns is accomplished by sequentially providing a plurality of bit maps to the pixel panel.

11. The method of claim 1 wherein each site can be divided into a plurality of contiguous mini-sites, with each mini-sites including a portion of the pixel-sites of the respective site, and wherein the pixel elements are moved relative to the subject by sequentially scanning in a predetermined fashion throughout each of the mini-sites, so that the pixel-mask pattern eventually creates a contiguous image across the plurality of contiguous mini-sites.

12. The method of claim 11 wherein the contiguous mini-sites overlap.

13. The method of claim 1 wherein the pixel elements are moved by a vibrating mirror positioned between a light source and the pixel panel, and wherein the pixel element are manipulated responsive to the vibration of the mirror.

14. The method of claim 1 wherein the pixel elements are moved by a vibrating mirror positioned between the pixel panel and the subject, and wherein the pixel element are manipulated responsive to the vibration of the mirror.

15. The method of claim 1 wherein the pixel panel is a deformable mirror device and the step of creating a plurality of pixel elements includes selectively manipulating one or more mirrors in the deformable mirror device responsive to the provided sub-pattern.

16. A method for exposing a pixel-mask pattern on a subject, the method comprising the steps of:

dividing the pixel-mask pattern into a plurality of sub-patterns, each sub-pattern being directed to a specific group of pixel-sites in a plurality of sites on the subject;

providing one of the sub-patterns to a pixel panel for creating a plurality of pixel elements by selectively manipulating the pixel panel responsive to the provided sub-pattern;

simultaneously focusing the plurality of pixel elements to discrete, non-contiguous pixel sites;

simultaneously moving the plurality of pixel elements relative to the subject so that a single pixel element can scan one of the pixel sites during a cycle; and

providing a next one of the sub-patterns to the pixel panel responsive to the movement and responsive to the pixel-mask pattern so that within the cycle of a modified scanning movement, a first pixel site of a group receives a first value while the second pixel site of the group receives a second value different from the first value.