Lithographic projection apparatus and device manufacturing method

• US 20050134819A1
• Filed: 12/22/2003
• Published: 06/23/2005
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Holding NV
• Inventors: de Jager, Pieter Willem Herman
• Granted Patent: US 6,995,830 B2
• Time in Patent Office: Days
• US Class Current: 355/55
• 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 7/70866 of mask or workpiece
• CPC Class Codes: G03F 7/70916 Pollution mitigation, i.e. mitigating effect of contamination or debris, e.g. foil traps
• CPC Class Codes: G03F 7/70933 Purge, e.g. exchanging fluid or gas to remove pollutants

Abstract

A system and method is used to pattern a substrate. A projection beam received from a radiation system is patterned using an array of individually controllable elements. A portion of the projection beam is directed directly onto one of the individually controllable elements and collecting radiation reflected therefrom using each one of a first array of focusing elements. An image of the first array of focusing elements is projected onto a second array of focusing elements using a projection system, such that radiation reflected from one of the individually controllable elements is projected via one of the focusing elements in the first array of focusing elements and the projection system to one of the focusing elements in the second array which focuses the radiation onto a spot on the substrate.

Claims

1. A lithographic projection apparatus, comprising:

a radiation system that provides a projection beam of radiation;

an array of individually controllable elements that pattern the projection beam according to a desired pattern;

a substrate table that holds a substrate;

a first array of focusing elements each directing a portion of the projection beam directly onto one of the individually controllable elements and collect radiation reflected therefrom;

a projection system that projects an image of the first array of focusing elements onto a second array of focusing elements, the second array being operatively arranged such that radiation reflected from one of the individually controllable elements is projected via one of the focusing elements in the first array of focusing elements and the projection system to one of the focusing elements in the second array, which focuses the radiation onto a spot on the substrate.

2. The apparatus according to claim 1, wherein the portion of the radiation beam directed onto each individually controllable element is focused onto an active part of the controllable element.

3. The apparatus according to claim 1 , wherein the first array of focusing elements is arranged adjacent to the array of individually controllable elements and the radiation system is that substantially uniformly illuminates the array of focusing elements.

4. The apparatus according to claim 1, wherein said first array of focusing elements comprises an array of micro lenses and wherein each micro lens is that focuses radiation onto one of the individually controllable elements.

5. The apparatus according to claim 1, wherein said first array of focusing elements comprises positioned to be a final element in a path of the radiation before it is incident on the array of individually controllable elements.

6. The apparatus according to claims 1, wherein each of the individually controllable elements is a diffractive optical MEMS device, whereby at a first setting an active surface of said MEMS device acts as a plane reflector reflecting zero order radiation back into the corresponding one of the focusing elements in the first array of focusing elements and at a second setting said active surface of said MEMS device forms a grating that diffracts first order radiation away from the one of the corresponding focusing elements in the first array of focusing elements.

7. The apparatus according to claim 1, wherein the second array of focusing elements comprises an array of micro lenses.

8. The apparatus according claim 1, wherein the array of individually controllable elements and the first array of focusing elements are mounted in a gas tight enclosure.

9. The apparatus according to claim 8, wherein the gas tight enclosure is substantially evacuated.

10. The apparatus according to claim 8, wherein the gas tight enclosure is evacuated to less than about 100 mTorr.

11. An apparatus according to claim 8, wherein the gas tight enclosure is filled with a substantially pure, clean gas.

12. The apparatus according to claim 11, further comprising a gas inlet connected between said enclosure and a source of said gas, and a gas outlet from said enclosure, permitting said gas to be flushed through the enclosure.

13. The apparatus according to claims 1, wherein the array of individually controllable elements comprises a substrate with the individually controllable elements mounted on one side thereof;

and

the first array of focusing elements is mounted on the array of individually controllable elements so as to form a gas tight enclosure around the individually controllable elements.

14. The apparatus according to claim 13, wherein the gas tight enclosure is substantially evacuated.

15. The apparatus according to claim 13, wherein the gas tight enclosure is evacuated to less than about 100 mTorr.

16. An apparatus according to claim 13, wherein the gas tight enclosure is filled with a substantially clean and pure inert gas.

17. The apparatus according to claim 16, further comprising a gas inlet connected between said enclosure and a source of said gas, and a gas outlet from said enclosure, permitting said gas to be flushed through the enclosure.

18. The apparatus according to claim 1, wherein:

the array of individually controllable elements comprises a substrate with the individually controllable elements mounted on one side thereof;

a plate, substantially transmissive to the projection beam of radiation, is mounted on the substrate so as to form a gas tight enclosure around the individually controllable elements; and

the first array of focusing elements is mounted within the gas tight enclosure.

19. The apparatus according to claim 18, wherein the gas tight enclosure is substantially evacuated

20. The apparatus according to claim 18, wherein the gas tight enclosure is evacuated to less than about 100 mTorr.

21. An apparatus according to claim 18, wherein the gas tight enclosure is filled with a substantially clean and pure inert gas.

22. The apparatus according to claim 21, further comprising a gas inlet connected between said enclosure and a source of said gas, and a gas outlet from said enclosure, permitting said gas to be flushed through the enclosure.

23. The apparatus according to claim 1, further comprising an actuator that adjusts a position of the first array of focusing elements relative to the array of individually controllable elements.

24. An apparatus according to claim 1, further comprising actuators for adjusting positions of each of the focusing elements within said first array relative to one another.

25. A method for manufacturing a device, comprising:

providing a substrate;

providing a projection beam of radiation using a radiation system;

using an array of individually controllable elements to pattern the projection beam;

using a first array of focusing elements, each for directing a portion of the projection beam directly onto one of the individually controllable elements and collecting radiation reflected therefrom; and

using a projection system to project an image of the first array of focusing elements onto a second array of focusing elements, the second array being arranged such that radiation reflected from one of the individually controllable elements is projected via one of the focusing elements in the first array of focusing elements and the projection system to one of the focusing elements in the second array which focuses the radiation onto a spot on the substrate.

26. A method for patterning a substrate, comprising:

patterning a projection beam received from a radiation system using an array of individually controllable elements to pattern;

directing a portion of the projection beam directly onto one of the individually controllable elements and collecting radiation reflected therefrom using each one of a first array of focusing elements;

projecting an image of the first array of focusing elements onto a second array of focusing elements using a projection system, such that radiation reflected from one of the individually controllable elements is projected via one of the focusing elements in the first array of focusing elements and the projection system to one of the focusing elements in the second array which focuses the radiation onto a spot on the substrate.