Flexible monomer for smooth polymer surface

A method of forming a semiconductor device, the method comprising:

• depositing a first metal layer on a substrate surface with at least one feature formed thereon, the at least one feature including at least one opening, at least one sidewall, and a bottom, the at least one feature extending a feature depth from a top surface to the bottom, the first metal layer forming on the top surface, on the at least one sidewall, and on the bottom;
• exposing the substrate surface to one or more monomers to form a flowable polymer film on the first metal layer within the at least one feature, the flowable polymer film forming on the first metal layer on the bottom, the one or more monomers selected from one or more of amines with bi-functional groups, aldehydes with bi-functional groups, cyanates with bi-functional groups, ketones with bi-functional groups, and alcohols with bi-functional groups;
• selectively removing the first metal layer from the top surface and from the at least one sidewall;
• removing the flowable polymer film to expose the first metal layer on the bottom of the at least one feature;
• and
• selectively depositing a second metal layer on the first metal layer to fill the at least one feature.