We introduce a new algorithm (DFM Via Shift) to reposition vertical interconnect access (VIA) design patterns, considering the retargeted metal (both upper and lower layer) pattern, the user-defined max-shifting range, and the VIA design rule, for the purpose of achieving maximum metal coverage of VIAs. The DFM Via Shift algorithm considers VIAs that interact with each other based on spacing rules as a VIA cluster. All VIAs in a cluster are co-optimized, allowing for fully-covered VIAs with good positioning to be shifted to allow other, more critical VIAs to be optimized in some scenarios. We present the results of our research showing that the overall metal coverage of VIAs in 25nm node test chips can be significantly improved with repositioning. Nearly 95% of VIAs exposed out of metal after retargeting can be optimized to new, fully-covered positions in one of the test cases of the advanced node.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
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.