A method of forming a pattern in a photoresist includes forming a photoresist layer over a substrate, and selectively exposing the photoresist layer to actinic radiation to form a latent pattern. The latent pattern is developed by applying a developer composition to the selectively exposed photoresist layer to form a pattern. The developer composition includes a first solvent having Hansen solubility parameters of 15 pKa>9.5; and a second solvent having a dielectric constant greater than 18. The first solvent and the second solvent are different solvents.