Figure 2. DSA of lamella and cylinders on chemical line grating patterns.

(a–d) Scanning electron microscope images of lamella (top row) and cylinder (bottom row) forming block copolymers self-assembled on chemical line grating patterns with (a) 44 nm, (b) 47 nm, (c) 49 nm and (d) 52 nm. The white scale bar denotes 400 nm. (e,f) Defect density versus chemical pattern pitch for (e) lamellar and (f) cylindrical phase block copolymer films with representative scanning electron microscope images.