The improvement of photolithographic fidelity of two-dimensional structures through double exposure method

Qingqing Wenren; Hua Ding; Xin Li; Changjiang Sun; Jun Zhu; Qiang Wu

doi:10.1117/12.711979

26 March 2007 The improvement of photolithographic fidelity of two-dimensional structures through double exposure method

Qingqing Wenren, Hua Ding, Xin Li, Changjiang Sun, Jun Zhu, Qiang Wu

Author Affiliations +

Proceedings Volume 6520, Optical Microlithography XX; 65202I (2007) https://doi.org/10.1117/12.711979
Event: SPIE Advanced Lithography, 2007, San Jose, California, United States

Abstract

With the semiconductor fabrication groundrule approaching the 32 nm node, double exposure or patterning method with 1.35 NA immersion seems to be the primary candidate due to its relative easiness to implement when compared to the other two competitors, the high refractive index immersion and the 13.4 nm extremely ultraviolet (EUV) lithography. However, the splitting of one mask into two is not a trivial task. In this paper, we would like to discuss about the best splitting method for several typical 2D structures, such as the isolated opposing line (or space) end shortening, T-like structures with narrow gaps, etc. From our recent experimental studies, we have found that, for line and space photolithography, the optimized illumination condition has a sigma value very close to 0.5. When compared to the single exposure processes, which will typically use more annular condition, a sigma of 0.5 can generate worse process windows for isolated features. This will put more pressure on the precision of the already challenging optical proximity correction (OPC) because the doubly exposed patterns and singly exposed patterns follow two different models. In our study, we find that the extra degrees of freedom in the double exposure method can be utilized to repair some intrinsic printing deficiency, such as, line end shortening. In this paper, we will analyze each typical 2D structure and, for each splitting method of the typical 2D features we study, we will discuss its capabilities in realizing good process windows, the MEF, and OPC correction easiness.

Citation Download Citation

Qingqing Wenren, Hua Ding, Xin Li, Changjiang Sun, Jun Zhu, and Qiang Wu "The improvement of photolithographic fidelity of two-dimensional structures through double exposure method", Proc. SPIE 6520, Optical Microlithography XX, 65202I (26 March 2007); https://doi.org/10.1117/12.711979

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
12 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Semiconducting wafers

Photomasks

Lithium

Optical proximity correction

Diffusion

Electroluminescence

Photoresist materials

Show All Keywords

Keywords/Phrases

Search In:

Publication Years