Engineering Block Copolymers To Achieve Equal Surface Free Energy and Tunable χN For Directed Self-Assembly Applications*

Directed Self-Assembly (DSA) of block copolymers (BCPs) is a promising technique for creating well-defined nanoscale features. The suitable BCPs for this application demand both blocks have equal surface free energies (SFE), a high enough Flory-Huggins parameter (χ) for moderate phase separation but not so high as to prohibit defect annihilation, and high etch contrast. To date, the BCPs that meet these requirements are still very limited. Here we demonstrate a high throughput approach to create a series of BCPs with full pitch sizes from 8- 15 nm that meet all these requirements. Furthermore, the capability of incorporation of etch resistant elements is shown to enable potential pattern transfer. We believe the work here will broaden the scope for DSA suitable materials and promote the next generation of nanolithography.