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A Nd:yttrium–aluminum–garnet pulsed laser, with 1064 nm wavelength, 9 ns pulse width, and 0.9 J maximum pulse energy, is employed to irradiate in vacuum different metal targets (Al, Ti, Ni, Cu, Ta, W, Au, and Pb). In order to measure the erosion thresholds, the etching rates, and the chemical yields, a mass quadrupole spectrometer is interfaced to the vacuum chamber. Etching process shows a threshold, which ranges between 0.1 and 1.6 J/cm2 for lead and tungsten, respectively. Etching rates range between 0.3 and 10 μg/pulse for copper and lead, respectively. The irradiation produces chemical yields ranging between 0.04 and 0.6 atoms/100 eV for copper and lead, respectively. A simple theoretical approach is presented to justify obtained results. The objective of collected data concerns the possibility to use ejected atoms, neutral and ionized, in an electron cyclotron resonance ion source, in order to provide high current, multiply charge ion beams.

The thinning technique is based on a simple geometrical model, describing the changes in the surface topography during ion beam etching. A high ion beam density makes jt possible that a thinning with an incidence angle of 0.5–7° ( measured from the sample surface) can take place within a reasonable time. Our method is applicable to a wide range of materials and to XTEM preparation.

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A Nd:YAG pulsed laser is employed to irradiate different metals in vacuum at the ECLISSE facility of the Laboratorio Nazionale del Sud, Catania, INFN. Laser pulse energy, 9 ns in width, ranges between 100 and 900 mJ. The ejection of atoms by means of laser irradiation is studied in terms of angular distribution, laser etching yield and film thickness deposited on a substrate. Light elements (Ni, Cu) show an angular distribution that is larger than heavy ones (W, Pb). A theoretical approach, applied to fit experimental data, indicates that the distribution depends on the high power of cos θ and that the flow velocity of ejected atom ranges between 27 000 and 88 000 m/s and the kinetic energy of ejected species ranges between 0.7 and 4.4 keV.

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A simple lumped component diode model is presented including a representation of conductivity modulation, in addition to the usual characterization by diffusion capacitance, transition capacitance, and an ideal junction. It is shown that this model employed in a switching circuit exhibits the overshoot and oscillation characteristic of diodes at high forward currents, as well as the usual charge storage effects for the reverse transient. Using small-signal analysisit is shown that in some cases the model possesses an inductive impedance which is also characteristic of diodes at high forward currents.