Patent ID: 6622294
Filing Date: 2003-09-16
Classification: G06F,H01L

Abstract:
A method comprising:determining a priority for a placement of a set of signal lines in a gridless layout of an integrated device by prioritizing the signal lines based on geometric constraints, shielding constraints and previously routed signal and/or power lines; placing a most constrained signal line from the set of signal lines based on previously routed signal lines, previously routed power lines and/or shielding requirements, wherein placing the most constrained signal line comprises placing a selected signal line in a first available track, possibly adjacent to a previously placed shield line and/or a previously placed power line and placing a shield line without an associated polarity, if necessary, adjacent to the placed selected signal line according to a predetermined policy; re-determining the priority of the remaining signal lines in the set of signal lines; and assigning polarities to shield lines previously placed without associated polarities such that the shielding lines and/or previously placed power lines satisfy a predetermined power pitch.