Document EPL, 82 (2008) 36002
DOI: 10.1209/0295-5075/82/36002
Synthesis of 
-Al2O3 thin films using reactive high-power impulse magnetron sputtering
E. Wallin1, T. I. Selinder2, M. Elfwing2 and U. Helmersson1 1 Plasma Coatings Physics Division, IFM Material Physics, Linköping University - SE-581 83 Linköping, Sweden, EU
2 Sandvik Tooling AB - SE-126 80 Stockholm, Sweden, EU
eriwa@ifm.liu.se
received 18 February 2008; accepted in final form 12 March 2008; published May 2008
published online 23 April 2008
Abstract -alumina coatings have been deposited directly onto cemented-carbide
and Mo substrates at a temperature as low as 650 
C using reactive
high-power impulse magnetron sputtering (HiPIMS) of Al in an
ArO2 gas mixture. The coatings consisted of plate-like
crystallites, as revealed by scanning electron microscopy. phase
growth was retained over the studied range of substrate bias voltages (from
floating potential up to -100V), with films exhibiting a
slightly denser microstructure at higher bias voltages. X-ray diffraction
indicated that the -alumina grains had a preferred orientation of
(0001)-planes perpendicular to the substrate surface. X-ray analysis of
films deposited at 575 C indicated the presence of 
-alumina, whereas films grown at 500 C or lower were X-ray amorphous.
68.55.-a - Thin film structure and morphology.
81.15.Cd - Deposition by sputtering.
81.05.Je - Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides).
© EPLA 2008