A method for placing tiles in an integrated circuit has matched devices
that includes the steps of (1) calculating a metal spacing for tiles to
be placed adjacent to the matched device in the integrated circuit; (2)
calculating a lateral spacing for tiles to be placed adjacent to the
matched device in the integrated circuit; (3) placing tiles about the
matched device based on the metal spacing and the lateral spacing; (4)
performing a density test in an area around the matched device; and (5)
if a density test is not satisfied in the area around the matched device,
dividing the matched device into at least two subdevices and repeating,
with respect to each subdevice, the steps of calculating a metal spacing,
calculating a lateral spacing, and placing tiles about each subdevice.
The method is further adaptable to various kinds of matched devices
including poly resistors, diffused resistors, double-poly capacitors,
metal-insulator-metal capacitors, and fringe capacitors.