Precision Ion Energy & Flux Control For In-Situ Magnetron Deposition & Etching For Plasma-Assisted Material Synthesis At The Atomic Scale

This Phase II project addresses the need to improve our understanding and scientific knowledge of the temporal evolution of ion energy, mass, flux and directionality resulting from the application of a rapid voltage reversal on a dense plasma formed by high-power impulse magnetron sputtering. There is evidence that the positive pulse is separated into two regions: (1) a “Short” Kick where the resulting potential appears across the dense magnetic confinement zone and serves to accelerate ions award proportional to the gradient in B field, and (2) a “Long” kick where the potential diffuses across field lines and raises the plasma potential in the chamber resulting in local plasma sheaths around grounded surfaces. Ions accelerated early in the positive Kick pulse consist of dominantly metal from the dense self- sputtering HiPIMS plasma; whereas ions accelerated later in the positive pulse consist of mixed metal and sputtering gas ions from downstream plasma conforming the substrate sheath. Phase I demonstrated precision ion energy control with the Positive Kick and the pathway for further elucidation into controlling the relative ratios of target metal to argon ions, increasing metal ion energy for energetic implantation, and control of film densification without inclusions. These phenomena need to be characterized and validated for potential application for architectural glass, semiconductors, advanced microelectronics packaging and energy applications. This will be achieved through a University collaboration on precompetitive fundamental research will result in publications and broad dissemination via conferences, journals and centers, and work with industrial partners. A major benefit of the Positive KickTM is the ability to allow HiPIMS processes with insulating substrates where before RF bias potentials were swamped from the massive particle pulse from a 100x current density pulse. This technique is an enabler for processing insulating substrates such as glass. In terms of significance, the technique can improve adhesion, surface cleaning, residual stress material etching and perform oxidation/nitridation/carbonation steps with deposition for reactive applications. A technology that can both simplify and speed up the production of this cable would be an invaluable tool for microelectronics industries, energy production and storage, and advanced coatings for optical materials. The SBIR program will also support emerging small businesses and job creation in the Midwest.