Environmentally focused patterning and processing of polymer thin films by initiated chemical vapor deposition (iCVD) and oxidative chemical vapor deposition (oCVD)

Abstract

The new millennium has brought fourth many technological innovations made possible by the advancement of high speed integrated circuits. The materials and energy requirements for a microchip is orders of magnitude higher than that of "traditional" goods, and current materials management requirements for EHS friendly low-k processing require a 10% annual increase in raw materials utilization. Initiated Chemical Vapor Deposition (iCVD) is a low-energy, one step, solvent-free process for producing polymeric thin films This thesis describes the deposition of a novel low-k iCVD precursor, 1,3,5,7-tetravinyltetramethylcylcotetrasiloxane (V4D4). The high degree of organic content in the as-deposited film affords the ability to tune the film's properties by annealing. The incorporation of atmospheric oxygen at high temperatures enhances the mechanical and electrical properties of the films. Films annealed at 410'C have a dielectric constant of 2.15, hardness and modulus of 0.78 GPa and 5.4 GPa, respectively. These values are comparatively better than previously reported results for CVD low-k films. Environmentally friendly low-k processing encompasses materials and energy management in the entire integration process, including lithography. Colloidal lithography was combined with iCVD and capillary force lithography to create spatially addressable grafted polymer pattern nanostructures, without the need for expensive lithography tools. Using this method, we pattern our novel low dielectric constant polymer down to 25 nm without the need for environmentally harmful solvents. Furthermore, these grafted patterns were produced for a broad material set of functional organic, fluorinated, and silicon containing polymers. A variation of this process created amine functionalized biocompatible conducting polymer nanostructure patterns for biosensor applications. These were fabricated using grafting reactions between oxidative chemical vapor deposition (oCVD) PEDOT conducting polymers and amine functionalized polystyrene (PS) colloidal templates. Carboxylate containing oCVD copolymer patterns were used to immobilized fluorescent dyes. Fluorescent colloidal particles were assembled within dyed PEDOT-co-TAA copolymer nanobowl templates to create bifunctional patterns for optical data storage applications. Finally, UV and e-beam lithography were used to pattern covalently tethered vinyl monolayers for resist-free patterning of iCVD and oCVD polymers, using environmentally innocuous solvents.