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The retained dose of implanted ions is limited by sputtering. It is known that a sacrificial layer deposited prior to ion implantation can lead to an enhanced retained dose. However, a higher ion energy is required to obtain a similar implantation depth due to the stopping of ions in the sacrificial layer. It is desirable to have a sacrificial layer of only a few monolayers thickness which can be renewed after it has been sputtered away. We explain the concept and describe two examples: (i) metal ion implantation using simultaneously a vacuum arc ion source and filtered vacuum arc plasma sources, and (ii) Metal Plasma Immersion Ion Implantation and Deposition (MePIIID). In MePIIID, the target is immersed in a metal or carbon plasma and a negative, repetitively pulsed bias voltage is applied. Ions are implanted when the bias is applied while the sacrificial layer suffers sputtering. Low-energy thin film deposition – repair of the sacrificial layer – occurs between bias pulses. No foreign atoms are incorporated into the target since the sacrificial film is made of the same ion species as used in the implantation phase.

Publisher Summary In this chapter the use of vacuum arcs as switches and as loads are discussed in detail. The chapter begins with an introduction to pulsed power concepts and definitions. Several vacuum switches are mentioned, such as closing switches, RodArray switch, prototypical vacuum switch, and others. Pulsed power refers to the delivery of energy to a load in temporally short packages so that the power, or energy delivered per unit time, is quite large. Thus, while the average power may not be remarkable, the peak power may, in some instances, exceed the entire average power production capacity of civilized nations. Various types of machinery rely on such impulses of energy. These machines use pulsed power either because it is impractical to deliver the requisite high powers continuously, because the physics requires a short pulse, or because a critical process scales superlinearly with power, thereby giving an efficiency advantage when pulsed power is used. Pulsed power systems frequently use a pulseforming network to alter the shape of the power pulse delivered to the load from an exponential waveform to something more desirable for the given application; frequently a rectangular pulse is required. A properly designed network of capacitors and inductors can shape a power pulse so that a constant power is delivered for a certain time period. The distributed capacitance and inductance of parallel-plate or coaxial conductors can also be used for this purpose, forming the basis for operation of a pulse forming line (PFL).

Ion beam mixing is an established tool for tailoring the interfacial region between a thin film and the underlying substrate. Ion beams of gaseous species such as nitrogen or argon have been used most frequently for this purpose in the past. We have combined a vacuum arc plasma gun for the deposition of thin metal films with a vacuum arc ion source for the production of energetic metal ion beams. In this case the bombarding ion becomes an important constituent of the resulting interfacial layer. We have investigated the film and interface structure for deposited films of Cr, Co and Ag that have been bombarded with Pt ions of mean energy 80 keV. Strong intermixing is observed. The results suggest that novel ternary or mixed binary metal silicides can be synthesized in this way.

Publisher Summary This chapter highlights pulsed arc technology and plasma sources. Pulsed arc technology is particularly simple and inexpensive and has found application for surface and thin film research involving the preparation of small experimental samples, as the setup time required is minimal and the amount of material consumed is insignificant. Repetitively pulsed sources are normally operated at low duty cycle and the mean electrical power input and heat removal requirements are much reduced compared to DC sources. Generally, they are driven by a capacitor discharge although a switched DC supply is sometimes used, too. These thermal and electrical aspects provide a rough demarcation between pulsed and DC sources typically at pulse widths of order 0.1-1 second or less. Pulsed vacuum arc plasma sources have been made with pulse widths from sub-microsecond upwards. The physics of plasma generation at the cathode spots is basically the same for pulsed and DC sources but there are some interesting differences.Arc Geometry, arc circuitry and triggering are mentioned under source design. The plasma is stated to be formed from any solid metal, and is highly ionized, and in general contains a small macroparticle contamination; the ions are, in general, multiply-stripped, with a directed ion energy of from about 20 eV for low-mass species to about 200 eV for high-mass species.The chapter discusses thin film deposition and very high rate deposition.

The stable confinement of a fully ionized, high-beta plasma in a toroidal bicusp (Tormac) is discussed. The bicusp geometry is described along with ''shaker'' heating by magnetoacoustic waves propagating orthogonal to the internal toroidal magnetic field. (MOW)