Plasma Processing Xii

Plasma processing of materials is a critical technology to several of the largest manufacturing industries in the worldâ€"electronics, aerospace, automotive, steel, biomedical, and toxic waste management. This book describes the relationship between plasma processes and the many industrial applications, examines in detail plasma processing in the electronics industry, highlights the scientific foundation underlying this technology, and discusses education issues in this multidisciplinary field. The committee recommends a coordinated, focused, and well-funded research program in this area that involves the university, federal laboratory, and industrial sectors of the community. It also points out that because plasma processing is an integral part of the infrastructure of so many American industries, it is important for both the economy and the national security that America maintain a strong leadership role in this technology.

Plasma Processing of Semiconductors contains 28 contributions from 18 experts and covers plasma etching, plasma deposition, plasma-surface interactions, numerical modelling, plasma diagnostics, less conventional processing applications of plasmas, and industrial applications. Audience: Coverage ranges from introductory to state of the art, thus the book is suitable for graduate-level students seeking an introduction to the field as well as established workers wishing to broaden or update their knowledge.

Pattern transfer by dry etching and plasma-enhanced chemical vapor de position are two of the cornerstone techniques for modern integrated cir cuit fabrication. The success of these methods has also sparked interest in their application to other techniques, such as surface-micromachined sen sors, read/write heads for data storage and magnetic random access memory (MRAM). The extremely complex chemistry and physics of plasmas and their interactions with the exposed surfaces of semiconductors and other materi als is often overlooked at the manufacturing stage. In this case, the process is optimized by an informed "trial-and-error" approach which relies heavily on design-of-experiment techniques and the intuition of the process engineer. The need for regular cleaning of plasma reactors to remove built-up reaction or precursor gas products adds an extra degree of complexity because the interaction of the reactive species in the plasma with the reactor walls can also have a strong effect on the number of these species available for etching or deposition. Since the microelectronics industry depends on having high process yields at each step of the fabrication process, it is imperative that a full understanding of plasma etching and deposition techniques be achieved.

VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching. This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section, Deposition, discusses deposition techniques for VLSI such as sputtering metals for metallization and contacts, plasma-enhanced chemical vapor deposition of metals and suicides, and plasma enhanced chemical vapor deposition of dielectrics. The part on Lithography presents the high-resolution trilayer resist system, pulsed x-ray sources for submicrometer x-ray lithography, and high-intensity deep-UV sources. The last part, Etching, provides methods in etching, like ion-beam etching using reactive gases, low-pressure reactive ion etching, and the uses of inert-gas ion milling. The theory and mechanisms of plasma etching are described and a number of new device structures made possible by anisotropic etching are enumerated as well. Scientists, engineers, researchers, device designers, and systems architects will find the book useful.

TO THE SECOND EDITION In the nine years since this book was first written, rapid progress has been made scientifically in nuclear fusion, space physics, and nonlinear plasma theory. At the same time, the energy shortage on the one hand and the exploration of Jupiter and Saturn on the other have increased the national awareness of the important applications of plasma physics to energy production and to the understanding of our space environment. In magnetic confinement fusion, this period has seen the attainment 13 of a Lawson number nTE of 2 x 10 cm -3 sec in the Alcator tokamaks at MIT; neutral-beam heating of the PL T tokamak at Princeton to KTi = 6. 5 keV; increase of average ß to 3%-5% in tokamaks at Oak Ridge and General Atomic; and the stabilization of mirror-confined plasmas at Livermore, together with injection of ion current to near field-reversal conditions in the 2XIIß device. Invention of the tandem mirror has given magnetic confinement a new and exciting dimension. New ideas have emerged, such as the compact torus, surface-field devices, and the EßT mirror-torus hybrid, and some old ideas, such as the stellarator and the reversed-field pinch, have been revived. Radiofrequency heat ing has become a new star with its promise of dc current drive. Perhaps most importantly, great progress has been made in the understanding of the MHD behavior of toroidal plasmas: tearing modes, magnetic Vll Vlll islands, and disruptions.