Defect Precursor and Metal Reduction from DSAL Resist using Filtration and Ion Exchange

Toru Umeda, Shuichi Tsuzuki
2014 Journal of Photopolymer Science and Technology (Fotoporima Konwakai shi)  
Gel particle is a primal defect in block copolymer (BCP) layer in directed self assembly lithography(DSAL). We studied gel removal performance for various lithography process filters and found that nylon 6,6 membrane outperformed other membrane materials exerting adsorption performance similarly to the conventional chemical amplified resist (CAR) filtration. Contrary to the CAR, BCP is synthesized using metal polymerization initiator and the metal in the resist layer should be removed to
more » ... e removed to prevent potential impact to the device integrity failure or the yield loss. We also studied metal reduction from the BCP solution using ion exchange filter and particle removal filters. As a result, ion exchange filter effectively reduced metals from BCP solution as expected. In addition, unexpectedly, nylon 6,6 membrane best reduced some metal species in the BCP solution.
doi:10.2494/photopolymer.27.441 fatcat:gycqh3tk3vd2paidm2e26t3jee