Broad-angle multilayer mirror design

• US 7,522,335 B2
• Filed: 03/29/2004
• Issued: 04/21/2009
• Est. Priority Date: 03/29/2004
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Lee, Sang Hun, Goldstein, Michael
• Primary Examiner(s): NGUYEN, THONG Q
• Application Number:
  US10/811,607
• Publication Number:
  US 20050213198A1
• Time in Patent Office: 1,849 Days
• Field of Search: 359350-361, 359557-590
• US Class Current: 359/359
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G02B 5/0816 Multilayer mirrors, i.e. having two or more reflecting layers G02B5/0883, G02B5/0891 take precedence
• CPC Class Codes: G02B 5/0891 Ultraviolet [UV] mirrors apparatus for microlithography exposure G03F7/70; X-ray multilayer structures G21K1/06
• CPC Class Codes: G03F 7/70233 Optical aspects of catoptric systems, i.e. comprising only reflective elements, e.g. extreme ultraviolet [EUV] projection systems
• CPC Class Codes: G03F 7/70316 Details of optical elements, e.g. of Bragg reflectors, extreme ultraviolet [EUV] multilayer or bilayer mirrors or diffractive optical elements
• CPC Class Codes: G03F 7/70958 Optical materials or coatings, e.g. with particular transmittance, reflectance or anti-reflection properties
• CPC Class Codes: G21K 1/062 Devices having a multilayer structure
• CPC Class Codes: G21K 2201/067 Construction details

Abstract

According to one embodiment a broad-angle multilayer (ML) mirror system is disclosed. The ML mirror includes a multiple layer structure configured to provide uniform reflectivity over a wide range of angles with small phase shifts.

Claims

1. A broad-angle multilayer ML mirror comprising a multiple layer structure over a substrate to provide uniform reflectivity over a wide range of incident angles with small phase shifts, the multiple layer structure comprising Molybdenum/Silicon bi-layers with an extra thick layer of Molybdenum next to the substrate and an extra thick layer of Silicon near the substrate.

2. The broad-angle ML mirror of claim 1 wherein the extra thick layer of molybdenum is in a first bi-layer over the substrate.

3. The broad-angle ML mirror of claim 1 wherein the extra thick layer of Silicon is in a third bi-layer over the substrate.

4. An optical system having an extreme ultra-violet (EUV) radiation source, the optical system comprising:

a mask;

a wafer; and

a plurality of reflecting surfaces for imaging the mask on the wafer, including;

a broad-angle mirror having a multiple layer structure over a substrate to provide uniform reflectivity over a wide range of the angles with small phase shifts, the broad-angle mirror comprising bi-layers with an extra thick layer of Molybdenum next to the substrate; and

an extra thick layer of Silicon near the substrate.

5. The optical system of claim 4 wherein the extra thick layer of Molybdenum is in a first bi-layer over the substrate.

6. The optical system of claim 4 wherein the extra thick layer of Silicon is in a third bi-layer over the substrate.