Pattern formation methods

Methods of forming an electronic device, comprise: (a) providing a semiconductor substrate comprising one or more layers to be patterned; (b) forming a photoresist layer over the one or more layers to be patterned, wherein the photoresist layer is formed from a composition that comprises: a matrix polymer comprising a unit having an acid labile group; a photoacid generator; and an organic solvent; (c) coating a photoresist overcoat composition over the photoresist layer, wherein the overcoat composition comprises: a matrix polymer; an additive polymer; a basic quencher; and an organic solvent; wherein the additive polymer has a lower surface energy than a surface energy of the matrix polymer, and wherein the additive polymer is present in the overcoat composition in an amount of from 1 to 20 wt% based on total solids of the overcoat composition; (d) exposing the photoresist layer to activating radiation; (e) heating the substrate in a post-exposure bake process; and (f) developing the exposed film with an org