Plasma Immersion Ion Processing
Plasma immersion ion processing (PIIP) is a relatively new vacuum technology for the application of hard, wear-resistant coatings. Like conventional physical vapor deposition (PVD) methods, PIIP is used to deposit various coatings, but the non-line-of-sight PIIP approach allows simultaneous treatment of large components and complex shapes without requiring component manipulation.
Building on established capabilities in ion beam surface modification techniques, Southwest Research Institute (SwRI) is committed to the advancement of PIIP technology. The recent availability of inexpensive, high-power pulsed modulator equipment, and the inherent scalability of PIIP, lend an economy to this surface modification process which is difficult to match using other methods.
PIIP technology was originally developed at the University of Wisconsin and principally refined at Los Alamos National Laboratory (LANL). The PIIP process occurs as follows:
The versatility of the “plasma” approach to surface modification allows the use of any gas with the same equipment. Thus, a single vacuum chamber can use argon gas for sputter-cleaning or nitrogen gas for ion implantation. The same equipment can be used to deposit coatings from hydrocarbon gases or organometallic compounds.
PIIP techniques for the deposition of diamond-like carbon (DLC) from acetylene gas and chromium oxycarbide from chromium carbonyl have been demonstrated. Researchers at LANL have demonstrated the scalability of PIIP by simultaneously coating 16 m2 with DLC. Analysis of a large-scale PIIP-based DLC deposition process indicates that the treatment cost would be comparable to electrodeposited hard chrome. Thus, PIIP offers an affordable alternative to more expensive and smaller-scale processes for the deposition of coatings for tribological (wear and friction) applications.
SwRI can also perform plasma immersion ion implantation (PIII), which was principally refined at the University of Wisconsin. PIII efforts have concentrated primarily on nitrogen implantation to improve the wear resistance of metals, and also on other implantation processes for the semiconductor industry.
SwRI’s state-of-the-art PIII and PIIP facility uses combinations of ion implantation and coating deposition to engineer adherent coatings on the exterior surfaces of metals, plastics, and ceramics.
This flyer was published in April 2000. For more information
about plasma immersion ion processing, contact
Dr. Kent E. Coulter, Phone (210) 522-3196, Fax (210) 522-6220,
Engineering Division, Southwest Research Institute, P.O. Drawer 28510, San
Antonio, Texas 78228-0510.