US Patent 10073347 Semiconductor method of protecting wafer from bevel contamination

The present disclosure provides a method that includes coating an edge portion of a wafer by a first chemical solution including a chemical mixture of an acid-labile group, a solubility control unit and a thermal acid generator; curing the first chemical solution to form a first protecting layer on the edge portion of the wafer; coating a resist layer on a front surface of the wafer; removing the first protecting layer by a first removing solution; and performing an exposing process to the resist layer.