EB-X1: an accurate x-ray mask writer using a variable-shaped beam

Nobuo Shimazu; Takashi Watanabe; Tetsuo Morosawa; Hirofumi Morita; Youichi Kuriyama; Tatsuya Kunioka

doi:10.1117/12.191924

3 November 1994 EB-X1: an accurate x-ray mask writer using a variable-shaped beam

Nobuo Shimazu, Takashi Watanabe, Tetsuo Morosawa, Hirofumi Morita, Youichi Kuriyama, Tatsuya Kunioka

Proceedings Volume 2254, Photomask and X-Ray Mask Technology; (1994) https://doi.org/10.1117/12.191924
Event: Photomask Japan '94, 1994, Kawasaki City, Kanagawa, Japan

Abstract

The EB-X1 is an accurate X-ray mask writer with high-throughput that was developed by modifying one of our EB60 variable-shaped E-beam systems. For high resolution, we developed an electron optical system whose 50-nm beam edge sharpness, a 15 A/cm² beam current density, and 1.0-micrometers X 0.5-micrometers maximum beam size with an acceleration voltage under 30 keV were determined by proximity-effect Monte Carlo simulation. We adopt a three-pronged approach for accurate pattern placement. First, we improve the beam positioning resolution from 20 nm to 5 nm. Because we suppress mechanical vibration, we can attain a 11-nm standard mark detection accuracy, resulting in a 20-nm compensation accuracy in the beam deflection distortion and a 25-nm field stitching accuracy. Second, our new column with its short beam-path and demagnification image of variable-shaped beam optics can attain a beam position stability within 30 nm over two hours. Finally, the use of an electrostatic chuck to firmly hold the mask-substrate with little holding- deformation and large heat transmission reduces mask-substrate deformation to 23 nm during pattern writing. Experiments confirm the EB-X1 can write a 0.2-micrometers minimum-feature sized pattern, has a pattern placement accuracy of 50 nm (3 (sigma) ) and a high throughput approximately ten times higher than that of a conventional point-beam exposure system. Using optimized correction coefficients for a specific layer, an average pattern placement accuracy of 33 nm (3 (sigma) ) can be achieved. The EB-X1 is now being used in the X-ray mask fabrication process line at NTT LSI Laboratories.

Citation Download Citation

Nobuo Shimazu, Takashi Watanabe, Tetsuo Morosawa, Hirofumi Morita, Youichi Kuriyama, and Tatsuya Kunioka "EB-X1: an accurate x-ray mask writer using a variable-shaped beam", Proc. SPIE 2254, Photomask and X-Ray Mask Technology, (3 November 1994); https://doi.org/10.1117/12.191924

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