Novel, developer soluble anti-reflective coating compositions and methods of using those compositions are provided. The compositions comprise a polymer and/or oligomer having acid functional groups and dissolved in a solvent system along with a cross linker, a photoacid generator, and optionally a chromophore. The preferred acid functional group is a carboxylic acid, while the preferred crosslinker is a vinyl ether crosslinker. In use, the compositions are applied to a substrate and thermally crosslinked. Upon exposure to light (and optionally a post exposure bake), the cured compositions will decrosslink, rendering them soluble in typical photoresist developing solutions (e.g., alkaline developers). In one embodiment, the compositions can be used to form ion implant areas in microelectronic substrates.