Using Directed Self Assembly of Block Copolymer Nanostructures to Modulate Nanoscale Surface Roughness: Towards a Novel Lithographic Process

Nanoscale surface roughness is an important factor in determining the properties of surfaces and can affect the performance of a range of devices prepared by lithographic methods. Here, a method is reported, which enables modulation of the nanoscale roughness of surfaces through the directed self assembly (DSA) of positively charged polymersomes, composed of specifically designed block copolymers, onto negatively charged surfaces. Assembly of the polymersomes on surfaces can result in an increase in the nanoscale surface roughness; however, through a controlled annealing step we can also significantly reduce the nanoscale roughness of the original surface. The ability to decrease the roughness of lithographic patterns is expected to have a significant impact on the manufacture of integrated circuits.