Effect of ion energy on structure and composition of cathodic arc deposited alumina thin films
2005 (English)In: Plasma chemistry and plasma processing, ISSN 0272-4324, E-ISSN 1572-8986, Vol. 25, no 4, 303-317 p.Article in journal (Refereed) Published
The effect of energy supplied to the growing alumina film on the composition and structure has been investigated by varying substrate temperature and substrate bias potential. The constitution and composition were studied by X-ray diffraction and elastic recoil detection analysis, respectively. Increasing the substrate bias potential from -50 to -100 V caused the amorphous or weakly crystalline films to evolve into stoichiometric, crystalline films with a mixture of the alpha- and gamma-phase above 700 degrees C, and. gamma-phase dominated films at temperatures as low as 200 degrees C. All films had a grain size of less than 10 nm. The combined constitution and grain size data is consistent with previous work stating that. - alumina is thermodynamically stable at grain sizes less than 12 nm [McHale et al., Science 277, 788 ( 1997)]. In order to correlate phase formation with synthesis conditions, the plasma chemistry and ion energy distributions were measured at synthesis conditions. These results indicate that for a substrate bias potential of - 50V, ion energies in excess of 100 eV are attained, both from a high energy tail and the accelerated ions with charge greater than 1. These results are of importance for an increased understanding of the evolution of film composition and microstructure, also providing a pathway to. - alumina growth at temperatures as low as 200 degrees C.
Place, publisher, year, edition, pages
Springer Science Business Media , 2005. Vol. 25, no 4, 303-317 p.
alumina; ion energy; plasma chemistry; composition; microstructure
National CategoryMedical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-59680DOI: 10.1007/s11090-004-3130-yISI: 000230912400001OAI: oai:DiVA.org:liu-59680DiVA: diva2:353085