New Portable Conformable Mask Method For Excimer Laser Lithography

Minoru Takeda; Toshiro Tsumori

doi:10.1117/12.968417

1 January 1988 New Portable Conformable Mask Method For Excimer Laser Lithography

Minoru Takeda, Toshiro Tsumori

Proceedings Volume 0922, Optical/Laser Microlithography; (1988) https://doi.org/10.1117/12.968417
Event: Santa Clara Symposium on Microlithography, 1988, Santa Clara, CA, United States

Abstract

New PCM (Portable Conformable Mask) method for excimer laser lithography has been developed. It consists of RD2000N (Hitachi Chemical Co., Ltd) as the top imaging layer, and PMGI (Poly-dimethyl glutarimide, Shipley Co., Ltd) as the bottom planarizing layer. In order to evaluate several kinds of deep UV resists and to search for a suitable resist process, we constructed an excimer laser exposure system, which is composed of a KrF excimer laser emitting at 248 nm with a bandwidth of 0.005 nm, and all quartz projection optics with a numerical aperture of 0.30, and a reduction ratio of 1/5. The excimer laser can produce about 100 mJ per pulse in the narrow bandwidth region. Spectral narrowing was accomplished by inserting etalons within the laser optical cavity. The reticle pattern was transferred to the wafer through the reduction lens. The energy density was about 15 mJ/cm2 at the wafer. From the evaluations of resist materials using the exposure system, it has been shown that RD2000N has high sensitivity and high resolution capability at the wavelength of KrF excimer laser. In the experiments of the PCM method, 0.5 μm thick RD2000N top layer was exposed and developed with an aqueous developer. RD2000N has very strong absorption in deep UV region, so can function as an adequate contact mask for the PCM method. After the top layer was delineated, that pattern was transferred to 1.0 μm thick PMGI as the bottom layer with deep UV flood exposure and subsequent developing of PMGI. With the PCM method, we have achieved 0.5 μm line and space resist patterns with aspect ratio of 3. The method is free from RIE treatment and thought to be more practical than a typical tri-layer resist which needs oxygen RIE for the bottom layer patterning.

Citation Download Citation

Minoru Takeda and Toshiro Tsumori "New Portable Conformable Mask Method For Excimer Laser Lithography", Proc. SPIE 0922, Optical/Laser Microlithography, (1 January 1988); https://doi.org/10.1117/12.968417

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

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
6 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Excimer lasers

Semiconducting wafers

Lithography

Projection systems

Deep ultraviolet

Laser optics

Reactive ion etching

Show All Keywords

Keywords/Phrases

Search In:

Publication Years