A method (of generating a layout diagram) includes: generating a shell including wiring patterns in a first layer of metallization, the wiring patterns having long axes which are substantially aligned with corresponding tracks that extend in a first direction, the wiring patterns having a default arrangement which has, relative to the corresponding tracks, a first amount of free space; and refining the shell into a cell, the refining including selectively shrinking, in the first direction, one or more of the wiring patterns resulting in a second amount of free space, the second amount being greater than the first amount, increasing, in the first direction, one or more chosen ones of the wiring patterns (chosen patterns), and backfilling the second amount of free space with one or more of at least one dummy pattern or at least one wiring pattern.