A method of manufacturing a semiconductor structure includes forming a precursor structure including a plurality of conductive pads on a substrate, an etch stop layer between the conductive pads, and an UBM layer on the conductive pads and the etch stop layer. A plurality of mask structures are formed on the UBM layer, and a plurality of openings are formed between thereof. Each of the mask structures is located on one of the conductive pads, and the openings expose a first portion of the UBM layer. A supporting layer is formed in the openings. The mask structures are removed to form a plurality of cavities exposing a second portion of the UBM layer. A conductive material layer is formed in the cavities. The supporting layer is removed. The first portion of the UBM layer is removed to form a plurality of conductive bumps separated from each other.