Design rules are maintained and released by a semiconductor foundry for its customers (layout designers of integrated circuits) to follow. Restrictive design rules (RDRs) curtail some of the "freedom" layout designers have traditionally had with regular design rules in less advanced process technologies. To achieve and maintain an acceptable return on investment

Return on investment

Return on investment is one way of considering profits in relation to capital invested. Return on assets , return on net assets , return on capital and return on invested capital are similar measures with variations on how “investment” is defined.Marketing not only influences net profits but also...

 for its customers and by extension for itself, a foundry may be compelled, for technological reasons, to adopt RDRs to better ensure the completed layout design of an integrated circuit

Integrated circuit

An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

is manufacturable with a desired yield in more advanced process technologies.

External links

(1) http://www.eetimes.com/news/latest/showArticle.jhtml?articleID=190301993

(2) http://www.edn.com/blog/1690000169/post/1230006923.html

(3) http://www.freelists.org/archives/fabacad/07-2006/msg00003.html