Kiyohiro Hine

Sputtering yields of Au by low-energy noble gas ion bombardment

Sputtering yields of gold (Au) by noble gas (He, Ne, Ar, Kr or Xe) ions have been measured in the low injection energy range 25–200 eV. The yield data presented here were obtained from mass-selected ion beam sputtering experiments, in which the ion beam has a very narrow energy spread and contains no impurity ions. The newly obtained yield data set, together with the fitting functions for the yield dependence on the injection energy, provide an accurate and reliable database for the study of fundamental physical mechanisms of sputtering phenomena at low energies, where experimental data had been scarce.

Measurement of Magnesium Oxide Sputtering Yields by He and Ar Ions with a Low-Energy Mass-Selected Ion Beam System

Sputtering yields of magnesium oxide (MgO) by He and Ar ion bombardment were measured at relatively low incident energies with monochromatic ion beams generated by a low-energy mass-selected ion beam system. The measured sputtering yields and their ion incident energy dependence are found to be significantly different from those proposed by an earlier study based on numerical simulations [S. J. Yoon and I. Lee: J. Appl. Phys. 91 (2002) 2487], which seems to be the only source of MgO sputtering yield data widely available in the community for a relatively wide range of ion incident energies. Given the fact that MgO is extensively used as barrier coating of plasma display panel (PDP) cells and the amount of sputtered MgO in PDP cells can affect their discharge characteristics to a large extent, our results indicate that a fundamental revision is urgently needed for the study of MgO sputtering by noble gas ion bombardment.

Experimental evaluation of CaO, SrO and BaO sputtering yields by Ne+ or Xe+ ions

Barrier coating materials used in plasma display panel (PDP) cells strongly affect the discharge voltages. Although magnesium oxide (MgO) is widely used for barrier coating in the current generation of commercial PDP cells, other alkaline earth oxides have been studied as alternatives and indeed some of them are now known to have lower discharge breakdown voltages for PDP cells, which would increase the energy efficiency of the cells. On the other hand, the resistance against physical sputtering is another critical parameter for barrier coating. In this work, sputtering yields of CaO, SrO and BaO by monochromatic Ne or Xe ion beams are obtained experimentally as functions of beam energy in the range 100–300 eV. Despite the large differences in mass among the targets and incident ions, sputtering yields are found to be similar in magnitude among them for a given incident energy.

Measurement of sticking probability and sputtering yield of Au by low-energy mass selected ion beams with a quartz crystal microbalance

A measurement system of sticking probability and sputtering yield in the energy range of 0–500 eV has been established with a low-energy mass selected ion beam system. The small change in mass of the substrate material by injected ions can be evaluated with the quartz crystal microbalance (QCM). In this study, sticking probabilities and self-sputtering yields of Au were measured as functions of the injection energy of Au ions.

Sputtering Yields of CaO, SrO, and BaO by Monochromatic Noble Gas Ion Bombardment

Although MgO is widely used for barrier coating in the current generation of commercial plasma display panel (PDP) cells, other alkaline earth oxides have been studied as alternatives to MgO because some of them have lower discharge breakdown voltages for PDP cells, which would increase energy efficiency of the cells. On the other hand, the resistance against physical sputtering is another critical parameter for barrier coating. In this work, sputtering yields of CaO, SrO, and BaO by monochromatic He+, Ar+, or Kr+ ion beams of normal incidence have been obtained experimentally at relatively low incident energies by a mass-selected ion beam system. Despite the large differences in mass among the target materials, sputtering yields are found to be similar in magnitude among them for a given incident energy. It has been also found that sputtering yields depend weekly on the mass of incident species among Ne+, Ar+, Kr+, and Xe+ ions.

Measurement of Au sputtering yields by Ar and He ions with a low-energy mass selected ion beam system

The Au sputtering yields by noble gas ions below 200 eV were measured with a low-energy mass selected ion beam system. Au sputtering yields by He and Ar ions were measured and found to incease monotonically with the ion injection energies. It was also found that the sputtering yields by He were much lower than those by Ar.