Fast & scalable pattern transfer via block copolymer nanolithography

A fully scalable and efficient pattern transfer process based on block copolymer (BCP) self-assembling directly on various substrates is demonstrated. PS-rich and PDMS-rich poly(styrene-b-dimethylsiloxane) (PS-b-PDMS) copolymers are used to give monolayer sphere morphology after spin-casting of solutions with selective solvents relative to the majority block.

The pattern is directly formed during spin-casting at room temperature, which takes less than 20 seconds, without any preliminary surface treatment of the substrate and without any subsequent annealing. The self-assembled BCPs are transformed into hard lithography masks by oxidation of PDMS in oxygen plasma.

The hard masks are then used to fabricate full wafer scale arrays of nano-pillars and nano-wells on various substrates, including polymers and silicon. The demonstrated BCP nano-lithography process opens up numerous applications not relying on long range lateral order, including fabrication of substrates for catalysis, solar cells, sensors, ultrafiltration membranes and templating of semiconductors or metals.