Abstract: A method of manufacturing a conductive layer is described. A substrate having a dielectric layer thereon is provided. The dielectric layer has a patterned structure and the patterned structure exposes a portion of the conductive layer. The surface of the substrate is cleaned in a first cleaning step and a cap layer is formed over the exposed portion of the conductive layer. Thereafter, the surface of the substrate is cleaned again in a second cleaning step to remove the residual cap layer on the surface of the dielectric layer. Finally, a dry cleaning step is performed to clean and dry the surface of the substrate.