Nano-scale effects of selective spin-on deposition

Abstract

Bottom-up patterning approaches are gaining traction as the trade-offs between resolution, throughput, and cost continually run into limitations for advanced semiconductor manufacturing technologies. With these constraints in mind, we have previously explored spin-on selective deposition of polymers over microscale features for ultimate use in ALD technologies. Two methods have previously been explored. The first approach considered a spin-on self-assembled monolayer (SAM) protecting either a metal or dielectric pre-pattern followed by a selective spin-on polymer coating. The second approach customized a synthetic fluorinated polymer tailoring the surface energies to the structures and sizes of interest in order to achieve selective deposition. In this work, pre-patterned copper and dielectric patterns are explored for selective deposition using pitch ranges from 128nm – 1000nm. A combination of spin-on SAMs along with custom synthesized polymers are studied. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) are used to characterize final polymer coatings and the impact of polymer structure, solution concentration, and processing conditions will be discussed. Ultimately, it will be shown that the combination of both spin-on SAMs and custom synthesized polymers successfully results in selective deposition over nanometer scale patterns, increasing previous resolution by two orders of magnitude.