High-density Plasma for Efficient Manufacturing of Electronic Devices

South Dakota State University, Brookings SD

Investigators

Abstract

Plasma technology plays a critical role in manufacturing of electronic devices, such as flat panel displays, computer chips, and solar panels. Industry plasmas currently used for manufacturing suffer from multiple limitations, including low plasma density (which slows processing), poor uniformity over large areas, contamination of plasma and the resulting materials, and inefficient energy use. This award supports fundamental research on high-density plasma using a unique magnetically enhanced inductive plasma source. New knowledge obtained from the research will lead to novel plasma sources that enable efficient manufacturing of electronic devices and various thin-film products, significantly reducing the costs of consumer electronics, promoting the adoption of clean energy, and reducing the negative impact of manufacturing on the environment. This project will strengthen university-industry collaboration and economic competitiveness of the U.S. electronics industry. It will also contribute to workforce development by training students and attracting local tribal students to science and engineering. Industry plasmas are created by strong electromagnetic fields. The efficiency of plasma processing is mainly determined by plasma density, plasma temperature, and energy distribution of electrons and ions. Conventional low-density plasmas are excited by unconfined electromagnetic fields that allow energetic electrons to escape easily from the plasma region, while high-density plasmas can be created by confined electromagnetic fields that retain energetic electrons within the plasma region to greatly extend their lifetime. The confined electric and magnetic fields act simultaneously and have interaction effects on the plasma. Little is known about the properties of high-density plasma created by confined electromagnetic fields and the effects of the primary induction parameters (excitation frequency and magnetic field distribution) on plasma properties. To fill this knowledge gap, the research team will perform three tasks. First, establish a plasma simulation model using dedicated software COMSOL to describe fundamental plasma properties (including plasma density, plasma temperature, and energy distribution of electrons and ions). Second, use the established model to predict effects of excitation frequency and magnetic field distribution on plasma properties. Finally, verify some of the predicted results by experiments. For example, plasma density and electron energy distribution at a limited number of points of the plasma region will be measured using a Langmuir probe, and plasma density over the entire plasma region will be indirectly measured using an optical emission spectrometer.