01380nas a2200229 4500008003900000022001300039245009800052210006900150260001200219300001100231490000800242520068000250653001400930653001500944653002300959653002200982653002001004100002201024700001701046700001901063856006801082 2013 d a0003695100aSpectroscopic imaging of self-organization in high power impulse magnetron sputtering plasmas0 aSpectroscopic imaging of selforganization in high power impulse  c07/2013 a0541040 v1033 a

Excitation and ionization conditions in traveling ionization zones of high power impulse magnetron sputtering plasmas were investigated using fast camera imaging through interference filters. The images, taken in end-on and side-on views using light of selected gas and target atom and ion spectral lines, suggest that ionization zones are regions of enhanced densities of electrons, and excited atoms and ions. Excited atoms and ions of the target material (Al) are strongly concentrated near the target surface. Images from the highest excitation energies exhibit the most localized regions, suggesting localized Ohmic heating consistent with double layer formation.

10aAluminium10aionization10aIonizing radiation10aplasma ionization10avisible spectra1 aAndersson, Joakim1 aNi, Pavel, A1 aAnders, André uhttps://facades.lbl.gov/publications/spectroscopic-imaging-self01624nas a2200193 4500008004100000245010000041210006900141260001200210490000700222520098500229653002401214653000901238653001301247653003401260653002801294100001701322700001901339856007201358 2010 eng d00aSupersonic metal plasma impact on a surface: an optical investigation of the pre-surface region0 aSupersonic metal plasma impact on a surface an optical investiga c04/20100 v433 a

Aluminum plasma, produced in high vacuum by a pulsed, filtered cathodic arc plasma source, was directed onto a wall where if formed a coating. The accompanying "optical flare" known from the literature was visually observed, photographed, and spectroscopically investigated with appropriately high temporal (1 μs) and spatial (100 μm) resolution. Consistent with other observations using different techniques, it was found that the impact of the fully ionized plasma produces metal neutrals as well as desorbed gases, both of which interact with the incoming plasma. Most effectively are charge exchange collisions between doubly charged aluminum and neutral aluminum, which lead to a reduction of the flow of doubly charged before they reach the wall, and a reduction of neutrals as the move away from the surface. Those plasma-wall interactions are relevant for coating processes as well as for interpreting the plasma properties such as ion charge state distributions.

10acathodic arc plasma10aions10aneutrals10aoptical emission spectroscopy10aplasma-wall interaction1 aNi, Pavel, A1 aAnders, André uhttps://facades.lbl.gov/publications/supersonic-metal-plasma-impact01049nas a2200121 4500008004100000050001500041245009000056210006900146520059600215100002200811700001900833856007500852 2008 eng d aLBNL-1641E00aSelf-sputtering far above the runaway threshold: an extraordinary metal ion generator0 aSelfsputtering far above the runaway threshold an extraordinary 3 a

When self-sputtering is driven far above the runaway threshold voltage, energetic electrons are made available to produce excess plasma far from the magnetron target. Ionization balance considerations show that the secondary electrons deliver the necessary energy to the remote zone. Thereby, such a system can be an extraordinarily prolific generator of useable metal ions. Contrary to other known sources, the ion current to a substrate can exceed the discharge current. For gasless self-sputtering of copper, the useable ion current scales exponentially with the discharge voltage.

1 aAndersson, Joakim1 aAnders, André uhttps://facades.lbl.gov/publications/self-sputtering-far-above-runaway01050nas a2200133 4500008004100000050001400041245013600055210006900191260002500260490000700285520052900292100001900821856007600840 2008 eng d aLBNL-171E00aSelf-sputtering runaway in high power impulse magnetron sputtering: The role of secondary electrons and multiply charged metal ions0 aSelfsputtering runaway in high power impulse magnetron sputterin aBoulder, COc08/20040 v923 a

Self-sputtering runaway in high power impulse magnetron sputtering is closely related to the appearance of multiply charged ions. This conclusion is based on the properties of potential emission of secondary electrons and energy balance considerations. The effect is especially strong for materials whose sputtering yield is marginally greater than unity. The absolute deposition rate increases ~ Q1/2, whereas the rate normalized to the average power decreases ~ Q-1/2, with Q being the mean ion charge state number.

1 aAnders, André uhttps://facades.lbl.gov/publications/self-sputtering-runaway-high-power01963nas a2200145 4500008004100000050001400041245012200055210006900177300001500246490000700261520143500268100001801703700001901721856007701740 2008 eng d aLBNL-679E00aSpatial distribution of average charge state and deposition rate in high power impulse magnetron sputtering of copper0 aSpatial distribution of average charge state and deposition rate a135210-1-60 v413 a

The spatial distribution of copper ions and atoms in high power impulse magnetron sputtering (HIPIMS) discharges was determined by (i) measuring the ion current to electrostatic probes and (ii) measuring the film thickness by profilometry. A set of electrostatic and collection probes were placed at different angular positions and distances from the target surface. The angular distribution of the deposition rate and the average charge state of the copper species (including ions and neutrals) were deduced. The discharge showed a distinct transition to a high current mode dominated by copper self-sputtering when the applied voltage exceeded the threshold of 535 V. For a lower voltage, the deposition rate was very low and the average charge state was found to be less than 0.4. For higher voltage (and average power), the absolute deposition rates were much higher, but they were smaller than the corresponding direct current (DC) rates if normalized to the same average power. At the high voltage level, the spatial distribution of the average charge state showed some similarities with the distribution of the magnetic field, suggesting that the generation and motion of copper ions is affected by magnetized electrons. At higher voltage, the average charge state increases with the distance from the target and locally may exceed unity, indicating the presence of significant amounts of doubly charged copper ions.

1 aHorwat, David1 aAnders, André uhttps://facades.lbl.gov/publications/spatial-distribution-average-charge01696nas a2200193 4500008004100000245018300041210006900224260001200293300001100305490000700316520097400323100002301297700002601320700002201346700001901368700002101387700001801408856007601426 2008 eng d00aThe structure and electron energy loss near edge structure of tungsten oxide thin films prepared by pulsed cathodic arc deposition and plasma-assisted pulsed magnetron sputtering0 astructure and electron energy loss near edge structure of tungst c04/2008 a1752160 v203 a

The microstructure and energy-loss near-edge structure (ELNES) of pulsed cathodic arc and pulsed magnetron sputtered WO3 thin films were investigated. It was found that the cathodic arc deposited material consisted of the α-WO3 phase with a high degree of crystallinity. In contrast, the magnetron sputtered material was highly disordered making it difficult to determine its phase. A self-consistent real space multiple scattering approach was used to calculate the NES of the various phases of WO3. Each phase was found to exhibit a unique NES allowing different phases of WO3 to be identified. The real space approach also allowed the origin of the main features in the NES to be investigated as the cluster size increased. The calculated NES for the room temperature γ-WO3 was found to compare well to previous X-ray absorption spectra and to NES obtained by full-potential band structure calculation.

1 aField, Matthew, R.1 aMcCulloch, Dougal, G.1 aLim, Sunnie, H.N.1 aAnders, André1 aKeast, Vicki, J.1 aBurgess, R.W. uhttps://facades.lbl.gov/publications/structure-and-electron-energy-loss01066nas a2200157 4500008004100000050001500041245006800056210006800124520054600192100001900738700001800757700001700775700002000792700002200812856007400834 2006 eng d aLBNL-5962100aSmoothing of ultrathin silver films by transition metal seeding0 aSmoothing of ultrathin silver films by transition metal seeding3 a

The nucleation and coalescence of silver islands on coated glass was investigated by in-situ measurements of the sheet resistance. Sub-monolayer amounts of transition metals (Nb, Ti, Ni, Cr, Zr, Ta, and Mo) were deposited prior to the deposition of silver. It was found that some, but not all, of the transition metals lead to coalescence of silver at nominally thinner films with smoother topology. The smoothing effect of the transition metal at sub-monolayer thickness can be explained by a thermodynamic model of surface energies.

1 aAnders, André1 aByon, Eungsun1 aKim, Dong-Ho1 aFukuda, Kentaro1 aLim, Sunnie, H.N. uhttps://facades.lbl.gov/publications/smoothing-ultrathin-silver-films02166nas a2200193 4500008004100000245011300041210006900154300001400223490000800237520149200245653003001737653001501767653002301782653001501805653003501820100002301855700001901878856007501897 2006 eng d00aStructural, optical and electrical properties of WOxNy films deposited by reactive dual magnetron sputtering0 aStructural optical and electrical properties of WOxNy films depo a2977-29830 v2013 a

Thin films of tungsten oxynitrides were prepared by dual magnetron sputtering of tungsten using argon/oxygen/nitrogen gas mixtures with various nitrogen/oxygen ratios. The presence of even relatively small amounts of oxygen led to close-to-stoichiometric WO3, with little incorporation of nitrogen, therefore the films were labeled as WOx(Ny). Oxygen had a great effect not only on the composition but on the structure of WOx(Ny) films, as shown by Rutherford backscattering and X-ray diffraction, respectively. Significant incorporation of nitrogen occurred only when the nitrogen partial pressure exceeded 89% of the total reactive gas pressure. Sharp changes in the stoichiometry, deposition rate, room temperature resistivity, electrical activation energy and optical band gap were observed when the nitrogen/oxygen ratio was high. The deposition rate increased from 0.31 to 0.89 nm/s, the room temperature resistivity decreased from 1.65 × 108 to 1.82 × 10− 2 Ω cm, the electrical activation energy decreased from 0.97 to 0.067 eV, and the optical band gap decreased from 3.19 to 2.94 eV upon nitrogen incorporation into the films. WOx(Ny) films were highly transparent as long as the nitrogen incorporation was low, and were brownish (absorbing) and partially reflecting as nitrogen incorporation became significant.

10aDual magnetron sputtering10aelectrical10aoptical properties10astructural10atungsten oxynitride thin films1 aMohamed, Sodky, H.1 aAnders, André uhttps://facades.lbl.gov/publications/structural-optical-and-electrical01095nas a2200169 4500008004100000245008300041210006900124260003000193520049900223653002000722653002200742653002400764653001500788100001900803700002400822856007900846 2003 eng d00aSurface Engineering of Glazing Materials and Structures Using Plasma Processes0 aSurface Engineering of Glazing Materials and Structures Using Pl aTampere, Finlandc06/20033 a

A variety of coatings is commercially produced on a very large scale, including transparent conducting oxides and multi-layer silver-based low-emissivity and solar control coatings. A very brief review of materials and manufacturing process is presented and illustrated by ultrathin silver films and chevron copper films. Understanding the close relation between manufacturing processes and bulk and surface properties of materials is crucial for film growth and self-assembly processes.

10anano-structures10aplasma processing10asurface engineering10athin films1 aAnders, André1 aMonteiro, Othon, R. uhttps://facades.lbl.gov/publications/surface-engineering-glazing-materials