An exemplary method for manufacturing printed circuit boards is provided. In the method, a copper clad substrate having a copper layer thereon is provided. A surface of the copper layer is roughened by applying an atmospheric pressure plasma thereto. A photoresist layer is formed on the roughened surface of the copper layer. The photoresist layer is exposed. The photoresist layer is developed to form a patterned photoresist layer, thereby exposing portions of the copper layer. The exposed portions of the copper layer exposed are removed so that the remaining portions of the copper layer form electrical traces. The patterned photoresist layer is removed.