Patent ID: 9230820
Filing Date: 2016-01-05
CPC Classification: B81C,C09D,G03F,H01L

Claim Text:
1. A method of directed self-assembly (DSA) of a block copolymer (BCP) having a natural pitch L 0 comprising: providing a substrate; forming on the substrate a patterned sublayer with generally parallel stripes having a stripe pitch L depositing on the patterned sublayer a solution comprising a first BCP of polymers A and B without functional groups, a polymer C with a functional group and a polymer D with a functional group; annealing said deposited solution to cause polymers C and D to self assemble and bind to the patterned sublayer; removing the first BCP and unbound polymers, leaving the self-assembled bound polymers C and D; repeating the steps of depositing said solution, annealing said deposited solution and removing the first BCP and unbound polymers; depositing on the self-assembled bound polymers C and D a layer of a second BCP of polymers C and D without functional groups; and annealing said layer of second BCP to cause DSA of the second BCP into alternating lines of polymers C and D, said alternating lines having a line pitch of approximately L