HIGH POWER IMPULSE MAGNETRON SPUTTERING
Fundamentals, Technologies, Challenges and Applications
High Power Impulse Magnetron Sputtering: Fundamentals, Technologies, Challenges and Applications se veut une introduction dans la pulvérisation magnétron par impulsions haute puissance (HiPIMS) mettant en avant les améliorations de cette nouvelle technologie par rapport aux moyens de pulvérisation conventionnelle. Ce livre présente les configurations expérimentales, la physique de cette décharge à travers des diagnostics et de la modélisation, mais aussi la croissance des films minces et leur spécificités.
High Power Impulse Magnetron Sputtering: Fundamentals, Technologies, Challenges and Applications is an in-depth introduction to High Power Impulse Magnetron Sputtering (HiPIMS) with an emphasis on how this novel sputtering technique differs from conventional magnetron processes in terms of hardware, discharge physics, thin film growth, and resulting thin film characteristics. The book is a result of an invitation from Elsevier in 2016 to write a first book entirely dedicated to HiPIMS. Roughly two and a half years later this is the result.
There is undoubtedly work that has been overlooked or not sufficiently dealt with in this book. Our ambition, however, has been to present a comprehensive text on the HiPIMS process, rather than a collection of loosely connected results found in the scientific literature. The main motivation is that HiPIMS, like so many topics in science, is a field in rapid development. With a great number of new findings presented every year, results are sometimes misinterpreted or contradictory. In addition, different descriptions of HiPIMS use their own terminology, which unfortunately varies depending on what source you are looking at. Altogether this presents a significant threshold for someone new to the field. If this book in any way can lower that threshold and stimulate more work on HiPIMS, then we have succeeded in our task.
So who should read this book? We hope that anyone involved in ionized physical vapor deposition will benefit from reading it, or at least a few chapters, depending on interest and expertize. The material, however, is aimed at a broader audience of professionals, practitioners, and students, who are familiar with basic concepts of plasma physics and thin films. We have tried to introduce various topics in such a way that someone new to HiPIMS will still be able to follow and possibly be even more motivated to try out this promising (but challenging) technology.
We start this book by an introduction to magnetron sputtering in Chapter 1, where we introduce the basic concepts needed to explore HiPIMS. Chapter 2 presents an overview of the historical development of the HiPIMS technique along with various high power pulsers that have been developed over the years. Chapters 3 and 4 are focused on experimental process characterization in HiPIMS and describe the role of electrons and heavy species (neutrals and ions), respectively. Typical characteristics of these species are presented to provide a solid understanding of the most important fundamental properties of the HiPIMS discharge. These findings are followed up in Chapter 5 using computational modeling. The main models are presented and compared to each other when possible. We also highlight some important modeling results, which have been selected to emphasize the added understanding brought by computational modeling, but also to validate certain model approaches or highlight model-specific results. Chapter 6 extends the fundamental knowledge gained in the previous chapters to reactive HiPIMS processes, which involves an introduction of basic sputtering physics in reactive gas mixtures as well as more specific aspects of surface and discharge processes related to reactive HiPIMS. Chapter 7 is an attempt at unifying and summarizing the most important concepts presented in mainly Chapters 3 – 6, and describes the underlying physical and chemical mechanisms giving rise to the observed process results and the consequences thereof. Finally, Chapter 8 discusses the use of HiPIMS to deposit thin films. The chapter is subdivided into several sections, each focusing on a different process-specific aspect related to certain film characteristics, where HiPIMS have been shown to have a great impact. Each chapter contains an extensive list of references to stimulate further reading.
A book like this one would not be possible without the contributions and invaluable input by all the expert coauthors and by many colleagues and friends. We do not list all the authors of the individual chapters, who have, besides their own texts, made great contributions to the book as a whole. With the risk of forgetting someone, we would still like to mention a few colleagues outside the author list, who deserve special recognition. In particular, we are deeply grateful to the talented T.J. Petty, who patiently listened to our descriptions and discussions and converted them into fantastic illustrations. We also acknowledge Felipe Cemin, who read and commented some of the chapters, while writing his Ph.D. thesis at Université Paris-Sud. Adrien Revel is acknowledged for his input on the numerical modeling, mainly related to the 2D and 3D particle simulations of short HiPIMS pulses.
Finally, we would like to conclude by thanking our families for all the support they have shown us during the course of writing this book and, in particular, for understanding why we had to work all those evenings (and most weekends).
Jon Tomas Gudmundsson
Paris–Linköping–Stockholm, June 2019