IP Library Granted Patent US 9,690,016
Granted Patent B2
US 9,690,016 · App. 14/696,331 · Granted Jun 27, 2017

Extreme ultraviolet reflective element with amorphous layers and method of manufacturing thereof

Inventors: Ralf Hofmann (Soquel, CA); Cara Beasley (Scotts Valley, CA); Vinayak Vishwanath Hassan (Santa Clara, CA); Majeed A. Foad (Sunnyvale, CA)
Assignee: APPLIED MATERIALS, INC.
G02B5/0891C23C14/06C23C14/14C23C16/24C23C16/45525G02B5/0833G02B5/0875G03F7/7015G03F7/70316G03F7/70958G21K1/062H05G2/008G21K2201/067
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 9,690,016
App. No.
14/696,331
Granted
Jun 27, 2017
Kind
B2
Abstract

An extreme ultraviolet reflective element and method of manufacture includes a substrate; a multilayer stack on the substrate, the multilayer stack includes a plurality of reflective layer pairs having a first reflective layer formed from silicon and a second reflective layer having a preventative layer separating a lower amorphous layer and an upper amorphous layer; and a capping layer on and over the multilayer stack for protecting the multilayer stack by reducing oxidation and mechanical erosion.

Claims (29)

1. A method of manufacture for an extreme ultraviolet reflective element comprising:

providing a substrate;

forming a multilayer stack on the substrate, the multilayer stack includes a plurality of reflective layer pairs having a first reflective layer formed from silicon and a second reflective layer having a preventative layer separating a lower amorphous molybdenum layer and an upper amorphous molybdenum layer; and

forming a capping layer on and over the multilayer stack for protecting the multilayer stack by reducing oxidation and mechanical erosion.

2. The method as claimed in claim 1 , wherein forming the multilayer stack includes forming the second reflective layer having the lower amorphous molybdenum layer having a thickness of less than 2.5 nanometers and the upper amorphous molybdenum layer having a thickness of less than 2.5 nanometers.

3. The method as claimed in claim 1 , wherein forming the multilayer stack includes forming the preventative layer between the lower amorphous molybdenum layer and the upper amorphous molybdenum layer for preventing crystallization of the lower amorphous molybdenum layer and the upper amorphous molybdenum layer.

4. The method as claimed in claim 1 , wherein forming the multilayer stack includes forming the preventative layer formed from carbon, ruthenium, niobium, nitrogen, molybdenum carbide, ruthenium molybdenum, boron, or boron carbide.

5. The method as claimed in claim 1 , wherein forming the multilayer stack includes forming the preventative layer by injecting carbon into a continuous stream of molybdenum to form an atomic mixture of carbon and molybdenum on the lower amorphous molybdenum layer.

6. The method as claimed in claim 1 , wherein forming the multilayer stack includes forming the preventative layer directly on the lower amorphous molybdenum layer and forming the upper amorphous molybdenum layer directly on the preventative layer.

7. The method as claimed in claim 1 , wherein forming the multilayer stack includes forming between 20 and 60 of the reflective layer pairs.

8. An extreme ultraviolet reflective element comprising:

a substrate;

a multilayer stack on the substrate, the multilayer stack includes a plurality of reflective layer pairs having a first reflective layer formed from silicon and a second reflective layer having a preventative layer separating a lower amorphous molybdenum layer and an upper amorphous molybdenum layer; and

a capping layer on and over the multilayer stack for protecting the multilayer stack by reducing oxidation and mechanical erosion.

9. The extreme ultraviolet reflective element as claimed in claim 8 , wherein the second reflective layer includes the lower amorphous molybdenum layer having a thickness of less than 2.5 nanometers and the upper amorphous molybdenum layer having a thickness of less than 2.5 nanometers.

10. The extreme ultraviolet reflective element as claimed in claim 8 , wherein the multilayer stack includes the preventative layer between the lower amorphous molybdenum layer and the upper amorphous molybdenum layer for preventing crystallization of the lower amorphous molybdenum layer and the upper amorphous molybdenum layer.

11. The extreme ultraviolet reflective element as claimed in claim 8 , wherein the multilayer stack includes the preventative layer formed from carbon, ruthenium, niobium, nitrogen, molybdenum carbide, ruthenium molybdenum, boron, or boron carbide.

12. The extreme ultraviolet reflective element as claimed in claim 8 , wherein the multilayer stack includes the preventative layer formed from an atomic mixture of carbon and molybdenum on the lower amorphous molybdenum layer.

13. The extreme ultraviolet reflective element as claimed in claim 8 , wherein the multilayer stack includes the preventative layer directly on the lower amorphous molybdenum layer and the upper amorphous molybdenum layer directly on the preventative layer.

14. The extreme ultraviolet reflective element as claimed in claim 8 , wherein the multilayer stack includes between 20 and 60 of the reflective layer pairs.

15. An extreme ultraviolet reflective element lithography system comprising:

an extreme ultraviolet light source which produces extreme ultraviolet light;

a reflective element that can reflect the extreme ultraviolet light, the reflective element including a multilayer stack on a substrate, the multilayer stack including a plurality of reflective layer pairs having a first reflective layer formed from silicon and a second reflective layer having a preventative layer separating a lower amorphous molybdenum layer and an upper amorphous molybdenum layer; and

a second deposition system for forming a capping layer on the multilayer stack for protecting the multilayer stack by reducing oxidation and mechanical erosion.

16. The system as claimed in claim 15 , wherein the lower amorphous molybdenum layer has a thickness of less than 2.5 nanometers and the upper amorphous molybdenum layer has a thickness of less than 2.5 nanometers.

17. The system as claimed in claim 15 , wherein the preventative layer between the lower amorphous molybdenum layer and the upper amorphous molybdenum layer prevents crystallization of the lower amorphous molybdenum layer and the upper amorphous molybdenum layer.

18. The system as claimed in claim 15 , the preventative layer is selected from carbon, ruthenium, niobium, nitrogen, molybdenum carbide, ruthenium molybdenum, boron, or boron carbide.

19. The system as claimed in claim 15 , the preventative layer comprising a mixture of carbon and molybdenum.

20. The system as claimed in claim 15 , the preventative layer directly on the lower amorphous molybdenum layer and the upper amorphous molybdenum layer directly on the preventative layer.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 11, 2015
From: HOFMANN, RALF; BEASLEY, CARA; HASSAN, VINAYAK VISHWANATH; FOAD, MAJEED A.
To: APPLIED MATERIALS, INC.
Reel/Frame 035610/0303 →
Continuity (2)
Provisional Application 62023478 · Jul 11, 2014
Related Publication 20160011345A1 · Jan 14, 2016