Micro-phase Separation Behavior Study of the Same System of a Novel Block Copolymer (PS-b-PC)

A novel high-chi block copolymer polystyrene-b-polycarbonate (PS-b-PC) of the same system with three samples (1, 2, 3) which contain an active -NH- group on the polymer backbone between the PS block and the PC block have been successfully synthesized. It is believed that the hydrogen bond between -NH- and Si-OH ( silanol ) plays a dominant role which is as a real driving force to promote vertical micro-phase separation under the neutral layer free condition. The periods in which the samples 1, 2 and 3 form a vertical layer micro-phase separation are 10.6, 11.2 and 12.3nm, respectively. Though experiments, the best micro-phase separation process conditions were found (annealing temperature 160-165 degrees C ; annealing time 10 min) and the relevant parameters of PS-b-PC are also given. The results show that sample 2 of high-chi (0.19) has better phase separation performance, lower line-edge roughness (LER) and line width roughness (LWR) than the other two samples. These diblock copolymer samples successfully achieved the directed self-assembly (DSA) of PS-b-PC under the condition that the designed silicon substrate groove did not need any neutral layer. Compared with the previously reported methods to orientation control BCPs with chi value and small vertical micro-phase separation while short-term thermal treatment demonstrates PS-b-PC as a rare and valuable candidate for advancing the field of nanolithography. This work will provide extremely important theories, valuable information and insights that apply to nanowire patterning by DSA in state-of-the-art semiconduction devices.