SBIR-STTR Award

Hard coatings have many applications in the transportation, manufacturing and electronics industries, including, for example coatings for wear and abrasion resistance, and cutting tools and molds. The application of many hard materials of potential interest (e.g. cubic boron nitride, hard carbon, silicon carbide) require bombardment by high fluxes of energetic particles during growth to produce high quality films. While plasma deposition processes are widely used, none is satisfactory for these materials and applications because of high cost and lack of precise deposition control. This project is to develop a high-density plasma ion source suitable for high-rate deposition of hard coatings over large areas. The ion source will be based on permanent magnet electron cyclotron technology in order to reduce cost. This source should be capable of generating uniform high-density plasmas over a 14 in. diameter region. Phase I will concentrate on the design, development, and demonstration of the plasma ion source. This phase will demonstrate the deposition process, but would not concentrate on deposition of hard coatings. Phase II will focus on ion-enhanced deposition of films such as cubic boron nitride, C3N4, fluorinated hard carbon films and diamond like carbon.

Commercial Applications and Other Benefits as described by the awardee:
This source would not only enable novel processes, but act as a link between laboratory and commercial application of ion assisted, hard coating deposition processes. As such, it has large benefits for the huge range of industries where hard coatings play a pivotal role, from cutting tools to magnetic disk media and heads.

Abrasion resistant coating technology, currently used in disk drives, would not provide adequate protection in future devices where the read/write head is flying ever closer to the disk. Research has indicated that the problem could be solved by developing a deposition technology capable of providing high fluxes of 100 eV carbon ions. The technique must be production worthy and allow reproducible depositions of films that are less than 50 D thick. This project will develop a high-density plasma source and deposition process based on electron-cyclotron resonance (ECR) plasma chemical vapor deposition. Phase I demonstrated the operation of a low-stray field electron resonance plasma source capable of ion currents greater than 3 mA/cm2 at 5% uniformity over 10 inch diameters. Using this source, silicon nitride, oxide and carbon films were deposited at rates of 50-1000 D/min with ion energies from 25-300 eV. The demonstration indicated that the appropriate ion flux and energy regime can be accessed to deposit hard amorphous-turbostratic carbon films over large areas. In Phase II, a process will be developed for depositing carbon overcoats of less than 50 D, with properties optimized for read/write heads. In addition, Phase II will develop analytical techniques and methods appropriate to the disk drive industry=s proprietary wear tests, as well real-time techniques to allow for precise process control.

Commercial Applications and Other Benefits as described by the awardee:
A production technology for the deposition of thin carbon overcoats should enable the manufacture of these systems for the worldwide disk drive market. Other applications include tribological coatings for micromechanical systems, wear coatings for machine tools, low dielectric constant diamond-like coatings (DLC) and fluorinated DLC films for integrated circuit interconnect isolation.