Directed self-assembly process implementation in a 300mm pilot line environment

The patterning capability of the directed self-assembly (DSA) of a 42nm-pitch block copolymer on an 84nm-pitch guiding pattern was investigated in a 300mm pilot line environment. The chemo-epitaxy guiding pattern was created by the IBM Almaden approach using brush materials in combination with an optional chemical slimming of the resist lines. Critical dimension (CD) uniformity, line-edge/line-width roughness (LER/LWR), and lithographic process window (PW) of the DSA process were characterized. CD rectification and LWR reduction were observed. The chemical slimming process was found to be effective in reducing pattern collapse, hence, slightly improving the DSA PW under over-dose conditions. However, the overall PW was found to be smaller than without using the slimming, due to a new failure mode at under-dose region.