15. A method for making an integrated circuit (IC), comprising: forming a material layer on a substrate; patterning a first photoresist layer on the material layer using a first photomask; etching the material layer through openings of the first photoresist layer; removing the first photoresist layer; patterning a second photoresist layer on the material layer using a second photomask and a third photomask; etching the material layer through openings of the second photoresist layer; and removing the second photoresist layer.
15. A method for making an integrated circuit (IC), comprising: forming a material layer on a substrate; patterning a first photoresist layer on the material layer using a first photomask; etching the material layer through openings of the first photoresist layer; removing the first photoresist layer; patterning a second photoresist layer on the material layer using a second photomask and a third photomask; etching the material layer through openings of the second photoresist layer; and removing the second photoresist layer. 20. The method of claim 15 , wherein the first, second, and third photomasks are designed according to an IC design layout having a plurality of IC features to be formed on the substrate.