Directed Self Assembly

•De-wetting was the main source of error •Too high of a PEO ratio will result in crystallization •30nm via holes can be achieved with the 29%mole PEO on PS under-layer •DSA is very sensitive to the surface Future Work •Use a lower weight, smaller polymer •Have a more rigorous cleaning procedure for samples before processing •Use different brush polymers •Take AFM images before annealing to see the effects of annealing on separation of the blocks Phase Diagram • Structure is determined by three factors • N is the degree of polymerization • x is the Flory interaction parameter • f is the volume fraction • The polymers used were large enough to be in the highlighted region and above •Reference research is shown by the dots PS-b-PDMS (blue) and PS-b-PEO (red)