US Patent 9768022 Advanced cross-linkable layer over a substrate

A lithography method is provided in accordance with some embodiments. The lithography method includes providing a substrate, forming a crosslinked layer over the substrate, wherein the crosslinked layer is in contact with the substrate, forming a patterned layer over the crosslinked layer, forming a pattern in the crosslinked layer and further in the substrate by using the patterned layer as a mask, treating the crosslinked layer by using a radiation source to transition the crosslinked layer to a de-crosslinked layer with a reduced molecular weight, and removing the de-crosslinked layer by using a solution that is not subject to cause damage on the substrate.