Abstract: Provided is a method of manufacturing a semiconductor device, the method including forming a via structure through a portion of a substrate; partially removing the substrate to expose a portion of the via structure; forming a protecting layer on the substrate to cover the portion of the via structure exposed by partially removing the substrate, the protecting layer including a photosensitive organic insulating material; curing the protecting layer to form a cured protecting layer; planarizing the cured protecting layer until a part of the via structure is exposed; and forming a pad structure to contact the part of the via structure exposed by planarizing the cured protecting layer.