Several technological approaches of applying photoresistive polymer for patterning the diamond seeding layer while minimizing damage of substrate surface is reported. Reactive ion etching (i.e., dry process) and wet photolithographical processing using two polymer layers are compared and combined as treatment techniques. Subsequently, diamond structures are deposited by microwave plasma enhanced chemical vapor deposition from a gas mixture of methane diluted in hydrogen. The highest efficiency for selected-area deposition, with the parasitic density as low as the technological limit of 105 cm−2, was achieved by combining the two treatment techniques. Technological advantages and limitation of dry and wet treatment process are pointed out.