282003 Thin Film, Big Difference – Atomic Layer Deposition Functionalized Oxide and Polymer Particles
Functionalization of insulating particles by Atomic Layer Deposition (ALD) could provide a unique range of electrical conductivity and outperform metal doped polymers for applications as replacements for metal electrodes in devices. The characterization and method of applying conductive metal ALD coatings on insulating materials to selectively produce precisely controlled properties is discussed.
In this study, functionalization of four types of oxide and polymer particles, 18 μm diameter or larger, was achieved by ALD of conformal metallic W thin films. Hollow and solid oxide particles as well as high and low surface area porous polymers were examined for conductivity range with increasing W film thickness. Particles were characterized for electrical and thermal conductivity using a four point probe planar van der Pauw test geometry. Measurable decreases in resistance over bare oxide support particles have been seen for film thicknesses of 25 nm or greater, additional decreases observed by increasing W thickness. Combining resistance characterization with ALD of conductive films on non-conductive particles allows for the development of a novel technology to selectively control electrical and thermal properties for defined applications.