APPLICATIONS OF TECHNOLOGY:

• Coatings for
• Metallization of semiconductors
• Superconducting films (e.g., Nb)
• Optical films on flat panel displays for computers, cell phones, PDAs
• Tools and automotive parts
• Medical implants
• Thin silver films for optical, photonic, and medical applications
• Coating devices used in space
• Thrusters for space vehicles

ADVANTAGES:

• Produces coatings with greater purity, density, conductivity, and durability
• Enables sputtering and film deposition in the vacuum of outer space
• Provides a safe, low-cost fuel for thrusters in space propulsion

ABSTRACT:

André Anders and Joakim Andersson of Berkeley Lab have invented a magnetron sputtering apparatus and process for producing films with greater purity by circumventing the need for a gas to initiate or sustain self-sputtering. In this invention, the sputtering is generated by a short cathodic arc or laser pulse. The particles that reach the substrate have a higher ion-to-atom ratio and energy level than in conventional sputtering, because no gas particles are present for potential collisions. This produces a purer film that approaches the theoretical limit of bulk density and, therefore, offers greater conductivity and durability. Using the plasma-triggering concept but allowing some reactive gas into the system, the range of coatings can be expanded to compound films while the benefits of high ion flux and ion energy are largely preserved.

The Berkeley Lab technology represents a significant  improvement over current high power impulse magnetron sputtering (HIPIMS) and other sputtering processes in which atoms and ions of the surrounding process gas are incorporated into the film, and the films produced are often compromised by impurities. Existing self-sputtering technology reduces, but does not eliminate, gas impurities.

In addition to improving coating technology, this Berkeley Lab technology can be used in the propulsion of spacecraft. A target metal, such as copper, would act as a low-cost, non-combustible, safe fuel that could rapidly sputter energetic atoms and ions. These particles would carry momentum away from the craft and propel it in the opposite direction. The apparatus could also be used to coat devices in the vacuum of space, where the initiating gas is not available. Thus, a worn part on a satellite or other piece of hardware such as a silver-coated mirror could be recoated without having to replace the part or return it to earth for recoating.

STATUS:

• Published patent application 20100264016 available at www.uspto.gov. Available for licensing or collaborative research.

To learn more about licensing a technology from LBNL see http://www.lbl.gov/Tech-Transfer/licensing/index.html.

FOR MORE INFORMATION:

Andersson J., A. Anders. “Gasless sputtering: Opportunities for ultraclean metallization, coatings in space, and propulsion,” Appl Phys Lett. 92:221503(2008).

Andersson J., A. Anders. “Self-sputtering far above the runaway threshold: An extraordinary metal-ion generator,” Phys Rev Lett. 102:045003(2009).

REFERENCE NUMBER: IB- 2498

SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:

• Improvements to High Power Impulse Magnetron Sputtering, IB-2473 

• Constricted Plasma Source, IB-1124 

• High Quality, Dense Thin Films Using Metal/Metal Alloy Additives, IB-1654 

• Atomically Flat Crystal Surfaces, IB-2549