Directed self-assembly of block copolymers for sub-10nm fabrication

Abstract

Directed self-assembly of block copolymers, based on microphase separation, is a promising strategy for high-volume and cost-effective nanofabrication. Over the past decades, manufacturing techniques have been made huge progress that it is now possible to engineer complex systems of heterogeneous materials around a few tens of nanometers (Such as 193i lithography). Further evolution of these techniques, however, is faced with difficult challenges not only because of diffraction limit, but also in prohibitively high capital equipment costs. Materials that self-assemble, on the other hand, spontaneously form nanostructures down to length scales at the molecular scale, but the micrometer areas or volumes over which the materials self-assemble with adequate perfection in structure is incommensurate with the macroscopic dimensions of devices and systems of devices of industrial relevance. Directed Self-Assembly (DSA) refers to the integration of self-assembling materials with traditional manufacturing processes. The key concept of DSA is to take advantage of the self-assembling properties of materials and at the same time meet the constraints of manufacturing. Technically DSA is similar to the double patterning in terms of resolution enhancement. In this report we will discuss the use of lithographically-defined chemically patterned surfaces to direct the assembly of block copolymer films for semiconductor manufacturing