A surgical system comprises an endoscopic instrument, a camera on the endoscopic instrument for obtaining video images of internal body tissues inside a patient's body via the endoscopic instrument, and a transmitter operatively connected to the camera for transmitting, over a telecommunications link to a remote location beyond a range of direct manual contact with the patient's body, a video signal encoding the video image. A receiver is provided for receiving actuator control signals from the remote location via the telecommunications link. The receiver feeds the signals to a robot actuator mechanism for controlling that mechanism to operate a surgical instrument insertable into the patient's body.

Automated surgical system and apparatus

Complex (dusty) plasmas: current status, open issues, perspectives

This updated version of the popular handbook further explains all aspects of physical vapor deposition (PVD) process technology from the characterizing and preparing the substrate material, through deposition processing and film characterization, to post-deposition processing. The emphasis of the new edition remains on the aspects of the process flow that are critical to economical deposition of films that can meet the required performance specifications, with additional information to support the original material. The book covers subjects seldom treated in the literature: substrate characterization, adhesion, cleaning and the processing. The book also covers the widely discussed subjects of vacuum technology and the fundamentals of individual deposition processes. However, the author uniquely relates these topics to the practical issues that arise in PVD processing, such as contamination control and film growth effects, which are also rarely discussed in the literature. In bringing these subjects together in one book, the reader can understand the interrelationship between various aspects of the film deposition processing and the resulting film properties. The author draws upon his long experience with developing PVD processes and troubleshooting the processes in the manufacturing environment, to provide useful hints for not only avoiding problems, but also for solving problems when they arise. He uses actual experiences, called 'war stories', to emphasize certain points. Special formatting of the text allows a reader who is already knowledgeable in the subject to scan through a section and find discussions that are of particular interest. The author has tried to make the subject index as useful as possible so that the reader can rapidly go to sections of particular interest. Extensive references allow the reader to pursue subjects in greater detail if desired. The book is intended to be both an introduction for those who are new to the field and a valuable resource to those already in the field. The discussion of transferring technology between R&D and manufacturing provided in Appendix 1, will be of special interest to the manager or engineer responsible for moving a PVD product and process from R&D into production. Appendix 2 has an extensive listing of periodical publications and professional societies that relate to PVD processing. The extensive Glossary of Terms and Acronyms provided in Appendix 3 will be of particular use to students and to those not fully conversant with the terminology of PVD processing or with the English language. This title is fully revised and updated to include the latest developments in PVD process technology. It includes 'War stories' drawn from the author's extensive experience emphasize important points in development and manufacturing. Appendices include listings of periodicals and professional societies, terms and acronyms, and material on transferring technology between R&D and manufacturing.

Handbook of physical vapor deposition (PVD) processing

The solution of electromagnetic scattering by a homogeneous prolate (or oblate) spheroidal particle with an arbitrary size and refractive index is obtained for any angle of incidence by solving Maxwell's equations under given boundary conditions. The method used is that of separating the vector wave equations in the spheroidal coordinates and expanding them in terms of the spheroidal wavefunctions. The unknown coefficients for the expansion are determined by a system of equations derived from the boundary conditions regarding the continuity of tangential components of the electric and magnetic vectors across the surface of the spheroid. The solutions both in the prolate and oblate spheroidal coordinate systems result in a same form, and the equations for the oblate spheroidal system can be obtained from those for the prolate one by replacing the prolate spheroidal wavefunctions with the oblate ones and vice versa. For an oblique incidence, the polarized incident wave is resolved into two components, the TM mode for which the magnetic vector vibrates perpendicularly to the incident plane and the TE mode for which the electric vector vibrates perpendicularly to this plane. For the incidence along the rotation axis the resultant equations are given in the form similar to the one for a sphere given by the Mie theory. The physical parameters involved are the following five quantities: the size parameter defined by the product of the semifocal distance of the spheroid and the propagation constant of the incident wave, the eccentricity, the refractive index of the spheroid relative to the surrounding medium, the incident angle between the direction of the incident wave and the rotation axis, and the angles that specify the direction of the scattered wave.

Light Scattering by a Spheroidal Particle

▪ Abstract In most space environments, dust particles are exposed to plasmas and UV radiation and, consequently, carry electrostatic charges. Their motion is influenced by electric and magnetic fields in addition to gravity, drag, and radiation pressure. On the surface of the Moon, in planetary rings, or at comets, for example, electromagnetic forces can shape the spatial and size distribution of micron-sized charged dust particles. The dynamics of small charged dust particles can be surprisingly complex, leading to levitation, rapid transport, energization and ejection, capture, and the formation of new planetary rings. This review briefly discusses the most important processes that determine the charge state of dust particles immersed in plasmas and the resulting dynamics on exposed dusty surfaces and in planetary magnetospheres.

Charged dust dynamics in the solar system

Laser light scattering measurements show that certain silicon etching plasmas produce a significant amount of in situ, particulate contamination. The particles are suspended at the sheath boundaries. Simultaneous measurement of plasma negative ions by the use of two‐photon laser‐induced fluorescence technique suggests that the particles are negatively charged and so are electrostatically trapped at the sheath boundaries. The parametric conditions for particle formation and growth in the plasma are identified. A mechanism for nucleation and growth is suggested involving formation of plasma negative ions from etch products, ion clustering with plasma species, and cluster growth into particles with electrostatic suspension and trapping. The particles drop onto the wafer when the rf is turned off. Implications for dry process technology are discussed.

In situ laser diagnostic studies of plasma‐generated particulate contamination

Particles generated in an argon plasma and suspended at the plasma/sheath boundary are localized by lateral trapping fields. In the commercial rf etching reactor used in this work, the particles and their motion in real time are observed by laser light scattering with the laser beam rapidly rastered in a plane parallel to the rf electrode. Repulsion between individual, relatively large particles is observed, verifying that there is significant negative charge on the particles. Two types of trapping regions are commonly seen: rings of particles around the outside edge of silicon wafers, and domes of particles over the centers of the wafers. It is shown that these effects are influenced by the topography of the electrode. In addition, particle densities >107 cm−3 for particles of diameter 0.2 μm are inferred from transmission studies for certain plasma conditions.

Particle trapping phenomena in radio frequency plasmas

Using a simple, inexpensive HeNe laser and a video camera to measure light scattering intensity and location, particulate contamination in an SiO2 sputtering process used in semiconductor manufacturing has been studied under actual process conditions in a class 10 cleanroom. Particulates were observed during all aspects of the sputtering process. It was seen that portions of the process which resulted in mechanical stress on the tool walls produced the greatest flux of particles inside the tool. However, the sputtering step was the major contributor to contamination in this chemically simple process, because of its long duration and the stress‐inducing nature of the plasma. The contamination level in this plasma is estimated to exceed the cleanroom ambient by three orders of magnitude. As in other process plasmas, the particles were suspended at the sheath/plasma boundary. It is argued that a relatively weak electrostatic field is required for gravitational counterbalance of these highly charged particles...

In situ plasma contamination measurements by HeNe laser light scattering: A case study

Particle contamination in a variety of plasma processes and tools has been studied using a real-time, in-situ detection technique, rastered laser light scattering. In agreement with previous studies, particles were suspended in the plasma. The distribution of particles, however, is highly ordered and predictable, in contrast to the randomness which typifies particulate behavior in uncharged environments, such as cleanrooms. The importance of electrostatic particle trapping is seen, as a means of understanding this ordered distribution of particles, for predictive performance of process tools in manufacturing, and for contamination control in processing tools. The implications of these results on future plasma processing is briefly discussed.

A Phenomenlogical Study of Particulates in Plasma Tools and Processes

The distribution and transport of particles in materials processing plasmas has been studied with a rastered laser light scattering technique. Contrary to expectation, the distribution of particles in a plasma processing tool is rarely random. Instead, structured clouds of particles form at the plasma/sheath boundary. The effect is attributed to trapping of the particles by weak electric field nonuniformities and the characteristic negative charge of isolated particles in a plasma. Field nonuniformities appear to be influenced by the topography and material design of the tool. For example, the presence of a Si wafer often induces significant particle trapping. Examples of particle trapping in a laboratory system are given, and similar phenomena are also verified in a manufacturing sputter deposition tool operating in a class 100 cleanroom. The implications of particle trapping in plasma processing are discussed.

Gary S. Selwyn

Papers

In situ laser diagnostic studies of plasma‐generated particulate contamination

Particle trapping phenomena in radio frequency plasmas

In situ plasma contamination measurements by HeNe laser light scattering: A case study

A Phenomenlogical Study of Particulates in Plasma Tools and Processes

Rastered laser light scattering studies during plasma processing: Particle contamination trapping phenomena