Fabrication of a complex-shaped mirror for an extreme ultraviolet lithography illumination system

Hideo Takino; Teruki Kobayashi; Norio Shibata; Masaaki Kuki; Akinori Itoh; Hideki Komatsuda

doi:10.1117/1.1591797

1 September 2003 Fabrication of a complex-shaped mirror for an extreme ultraviolet lithography illumination system

Hideo Takino, Teruki Kobayashi, Norio Shibata, Masaaki Kuki, Akinori Itoh, Hideki Komatsuda

Optical Engineering, Vol. 42, Issue 9, (September 2003). https://doi.org/10.1117/1.1591797

We propose and discuss several fabrication processes for a complex-shaped mirror, which is a fly-eye mirror, used in an extreme ultraviolet lithography (EUVL) illumination system. The mirror has a complex reflective surface consisting of many concave mirror elements that are sections of a sphere; the top of each element is arc shaped. In the present study, we focus on one process in which all elements are fabricated individually and then arranged side-by-side to form the mirror. Thus, as the first step in this process, we fabricate the arc-shaped elements made of invar with electroless nickel plating. The resultant reflective surfaces have a peak-to-valley (PV) surface accuracy of 0.31 μm. The surfaces have the rms roughnesses of about 0.23 and 0.35 nm in areas of 110×140 μm and 1×1 μm, respectively. The slope accuracies of the surfaces relative to the bottom surfaces are –166 and 43 arc-sec in the y and x directions, respectively. Thus, the mirror elements for the fly-eye mirror can be fabricated very accurately with smooth surfaces, although the mirror elements have a special shape compared to that of general optics.

©(2003) Society of Photo-Optical Instrumentation Engineers (SPIE)

Citation Download Citation

Hideo Takino, Teruki Kobayashi, Norio Shibata, Masaaki Kuki, Akinori Itoh, and Hideki Komatsuda "Fabrication of a complex-shaped mirror for an extreme ultraviolet lithography illumination system," Optical Engineering 42(9), (1 September 2003). https://doi.org/10.1117/1.1591797

Published: 1 September 2003

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available