Grand challenges in low temperature plasmas

Journal of Physics D: Applied Physics

Plasma, 2019

Scientific breakthroughs tend to come in spurts when unique societal, economical, and political circumstances conspire (knowingly or unknowingly) and create an environment ripe for creativity. The field of low temperature plasma (LTP) recently experienced such an upheaval, which this paper attempts to relate in some details. There have been “roadmap” papers published before, which look towards the future of the field, but all roads start somewhere and even “new” roads are often paved over older roads that were discovered and traveled by early pioneers. With the sharp decrease in funding for fusion research in the USA in the early 1990s the plasma science community was faced with a dire situation that threatened to choke off plasma physics advances. However, in the background and far from the visibility accorded to fusion research, a few laboratories were quietly engaged in innovative research that in due time revolutionized the LTP field and breathed new life into plasma science. Gr...

Physics of Plasmas, 2013

2008

cdn.intechopen.com

Plasma, 2020

For many decades non-equilibrium plasmas (NEPs) that can be generated at atmospheric pressure have played important roles in various material and surface processing applications [...]

arXiv (Cornell University), 2020

Goals of Initiative To initiate a national program in Low Temperature Plasma (LTP) to take advantage of the research opportunities of 3 rapidly growing areas (nanomaterial plasma synthesis, plasma medicine, microelectronics). The main theme is to achieve a fundamental understanding of Low Temperature Plasmas as they are applied to these different applications. This understanding will allow U.S. industry to meet the challenges of international competition. Programmatic Benefit The programmatic benefit of this initiative is that a fundamental understanding of the plasmas as they are applied to the areas of nanomaterial plasma synthesis, plasma medicine, and microelectronics will be developed. This will eventually replace the current Edisonian approach to applications research that is costly and inefficient. This is a major challenge because Low Temperature Plasmas are complex. They have low ionization and therefore neutrals, electrons, and ions interactions need to be understood. In all three of these application areas plasma chemistry plays a major role. In many cases the plasmas are not in equilibrium, not Maxwellian, and radiation effects are important. Furthermore, at low pressures the plasma mean free path or energy relaxation length is longer than the system size. Therefore, the boundary conditions impact the plasma volume of the system. More importantly the initiative addresses the critical needs of the U.S. microelectronics industry, see white paper by microelectronics industry leaders [1]. The research needs for microelectronics have rapidly changed over the last 5-10 years. Where the US once dominated in the production of semiconductor devices, now South Korea leads the world. Specifically, Samsung leads Intel in sale of such devices. Furthermore, there are concerns of state sponsored initiatives by China to modernize its economy, increase productivity, and use innovation to create economic growth. The initiative Made-In-China (MIC) 2025, looks to use innovation for future growth. In particular, China is targeting key industries to provide innovation including the microelectronics industry. An example of China becoming the leader of high-value manufacturing is their semiconductor purchases. In 2003 China was similar to the US (19.4% US, 18.5% China) in the purchase of semiconductors for the products it sold, but in 2019 the US has fallen to 11.9% and China dominates by consuming 60.5% of the world market [2]. These semiconductors are in the products China manufactures and sells to the world. The 2025 initiative has its goal to move China from being the largest consumer of

The current status of low temperature plasmas (LTPs) as a research area and technology driver producing societal benefit is discussed. The current science challenges are discussed in the context of the extreme dynamic range and intellectual diversity of the field of LTPs. The case is made that given this extreme dynamic range of science challenges and the broad range of motivating technology areas, it is neither possible nor prudent to define a single science discovery challenge that covers the entire field of LTPs. Given these conditions, we propose that the DOE Office of Fusion Energy Science, perhaps in partnership with the Office of Basic Energy Sciences, fund a broad science program in LTPs having an annual solicitation. The current science challenges would then be defined by the proposers. After a 3year ramp-up period, the steady state funding level would be $5,000,000/year. Comparisons are made to international activities in LTPs.

Vacuum, 2008

In the last few decades there has been an intense development in non-equilibrium (''cold'') plasma surface processing systems at atmospheric pressure. This new trend is stimulated mainly to decrease equipment costs by avoiding expensive pumping systems of conventional low-pressure plasma devices. This work summarizes physical and practical limitations where atmospheric plasmas cannot compete with lowpressure plasma and vice-versa. As the processing conditions for atmospheric plasma are rather different from reduced pressure systems in many cases these conditions may increase final equipment costs substantially. In this work we briefly review the main principles, advantages and drawbacks of atmospheric plasma for a better understanding of the capabilities and limitations of the atmospheric plasma processing technology compared with conventional low-pressure plasma processing.

IEEE Transactions on Plasma Science, 2009

Cyclonic atmospheric pressure plasma with lowtemperature nature has been investigated. High-speed rotating nonthermal atmospheric plasma jets were utilized as RF plasma sources to provide the gas velocities required to generate the cyclonic gas flow patterns. It was shown that the plasma temperature could be controlled by operational parameters. The experimentally measured gas phase temperature was around 30 • C-85 • C, indicating that this cyclonic atmospheric pressure plasma can treat polymers without unfavorable thermal effects. This type of low-temperature atmospheric plasma can provide a novel technique for large-scale surface modification of heat-sensitive materials.