Self-Aligned Thin-Film Patterning by Area-Selective Etching of Polymers

Patterning of thin films with lithography techniques for making semiconductor devices has been facing increasing difficulties feature sizes shrinking to the sub-10 nm range, and alternatives have actively sought from area-selective film deposition processes. Here, an entirely new method is introduced self-aligned thin-film patterning: gas-phase etching polymers. The reactions are selective materials underneath Either O2 or H2 can be used as etchant gas. After diffusing through polymer catalytic surfaces, gas molecules dissociated into their respective atoms, which then readily react polymer, it away. On noncatalytic remains. For example, polyimide poly(methyl methacrylate) (PMMA) were selectively oxidatively removed at 300 °C Pt Ru, while on SiO2 they stayed. CeO2 also showed a clear effect oxidative removal PMMA. In H2, most active surfaces catalysing hydrogenolysis PMMA Cu Ti. was followed by atomic layer iridium using patterned growth-inhibiting SiO2, eventually resulting in dual side-by-side formation metal-on-metal insulator (polymer)-on-insulator. This demonstrates that when innovatively combined and, lift-off patterning processes, processes will open possibilities fabrication advanced challenging devices.