The effect of the microstructure and the surface topography on the electrical properties of thin Ag films deposited by high power pulsed magnetron sputtering
2008 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 202, no 11, 2323-2327 p.Article in journal (Refereed) Published
In this work thin silver (Ag) films are grown employing high power pulsed magnetron sputtering (HPPMS) for various pulse on/off time configurations, as well as by dc magnetron sputtering (dcMS), for reference. It is shown that the increase of the pulse off-time from 450 mu s to 3450 mu s, while the pulse on-time is kept constant at 50 mu s, results in an increase of the peak target current (I-Tp) from 3 A to 22 A. The increase of I-Tp is accompanied by an increase of the ion flux towards the growing film. This is particularly pronounced for I-Tp greater than 11 A. The microstructure, the surface topography and the electrical properties of Ag films grown at I-Tp = 11 A, I-Tp = 22 A and by dcMS are investigated, as a function of the film thickness d. It is shown that for d greater than 20 nin the electrical resistivity of films sputtered at I-Tp=22 A is similar to that of films grown by dcMS. Slightly higher values are measured for films grown at I-Tp = 11A. It is found that in this thickness range the film conductivity is strongly affected by the vertical grain size and the scattering of the charged carriers at the film interfaces. For d less than 15 nm the resistivity of films deposited at I-Tp = 22 A is substantially lower as compared to that of films grown by dcMS. Films deposited at I-Tp = 11 A exhibit also in this case a higher conductivity. In this thickness regime the electronic transport and, thus the conductivity are profoundly determined by the surface topography and the film density.
Place, publisher, year, edition, pages
Elsevier , 2008. Vol. 202, no 11, 2323-2327 p.
HPPMS; HiPIMS; silver films; conductivity
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-71485DOI: 10.1016/j.surfcoat.2007.08.028ISI: 000253930900020OAI: oai:DiVA.org:liu-71485DiVA: diva2:450206