Forbidden-area avoidance with spacing technique for layout optimization

Shi Chang Shi; Alfred K. Wong; Tung-Sang Ng

doi:10.1117/12.533640

3 May 2004 Forbidden-area avoidance with spacing technique for layout optimization

Shi Chang Shi, Alfred K. Wong, Tung-Sang Ng

Proceedings Volume 5379, Design and Process Integration for Microelectronic Manufacturing II; (2004) https://doi.org/10.1117/12.533640
Event: Microlithography 2004, 2004, Santa Clara, California, United States

Abstract

The use of subresolution assist features (SRAFs) in the photo mask is one of resolution enhancement techniques in photolithography, which can minimize linewidth variation caused by proximity effect. However, the process latitude with SRAFs through various pitches is not uniform. From the point of view of lithography, pitches with low process latitude, called forbidden areas, should be avoided. These forbidden areas exist often in the layout after routing since they are larger than the minimum clearance required in the design rules. In this paper, a pitch optimization method applied in the post-routing phase is proposed to avoid the forbidden areas. Experimental data of lithography techniques and geometric constraints from the layout are formulated into a constrained quadratic optimization problem. By using the spacing technique, wire segments in the affected area are adjusted to their new locations obtained from solving the optimization problem by quadratic programming. Examples show that the proposed method can avoid most forbidden areas in the layout after normal routing.

Citation Download Citation

Shi Chang Shi, Alfred K. Wong, and Tung-Sang Ng "Forbidden-area avoidance with spacing technique for layout optimization", Proc. SPIE 5379, Design and Process Integration for Microelectronic Manufacturing II, (3 May 2004); https://doi.org/10.1117/12.533640

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