ENME Webcast Archives

TRANSFORMING ENERGY LECTURE SERIES - SPRING 2008

Plasmas for Energy Efficient Materials Processing

Lecturer: Mark Kushner - Iowa State University

Original Air Date: Thursday, January 31st at 2:00pm

Abstract: Plasmas find extensive use in every day technologies, either directly such as lighting and plasma display panels, or indirectly through their use in manufacturing of a wide range of products, from microelectronics to commodity polymers. Plasmas act as a power transfer medium in which power from the wall plug is converted to the kinetic energy of electrons and ions. These energetic charged species, through collisions in the gas phase and with surfaces, produce chemically active species. These species modify materials, as in microelectronics fabrication, or are themselves the end product, as in photons. Plasmas are potentially highly energy efficient sources of activation energy due to our ability to customize the distribution of electron and ion energies to selectively produce desired excited states and surface species. Improvements in those plasma activated processes have the potential for large improvements in energy utilization. For example, 22 percent of the electrical power generated in the United States is used for lighting and a large fraction of that is used to excite a single excited state of the mercury atom in plasma based lighting. In this talk, results from computational investigations of plasma activated chemistry for manufacture of high value materials will be discussed with emphasis on highly energy efficient and selective processes. Examples will be used from two extremes of materials processing: low pressure plasmas for microelectronics fabrication and atmospheric pressure plasma functionalization of biomaterials. Means of optimizing these processes for desired material characteristics while minimizing energy use will be discussed.