Low Temperature Reactive Sputtering of Thin Aluminum Nitride Films on Metallic Nanocomposites

Abstract

Piezoelectric aluminum nitride thin films were deposited on aluminum-molybdenum (AlMo) metallic nanocomposites using reactive DC sputtering at room temperature. The effect of sputtering parameters on film properties was assessed. A comparative study between AlN grown on AlMo and pure aluminum showed an equivalent (002) crystallographic texture. The piezoelectric coefficients were measured to be 0.5±0.1 C m-2 and 0.9±0.1 C m-2, for AlN deposited on Al/0.32Mo and pure Al, respectively. Films grown onto Al/0.32Mo however featured improved surface roughness. Roughness values were measured to be 1.3nm and 5.4 nm for AlN films grown on AlMo and on Al, respectively. In turn, the dielectric constant was measured to be 8.9±0.7 for AlN deposited on Al/0.32Mo seed layer, and 8.7±0.7 for AlN deposited on aluminum; thus, equivalent within experimental error. Compatibility of this room temperature process with the lift-off patterning of the deposited AlN is also reported.

Fabrication and characterization of AlN-based flexible piezoelectric pressure sensor integrated into an implantable artificial pancreas

“…The biaxial stress can be calculated taking into account the c-axis strain (evaluated from XRD (0002) peak position) and the theoretical stiffness tensor of AlN. It is about 1.5 GPa, similar to values already reported in literature for sputtered AlN thin films 17 . Obviously, this is an approximation based on the hypothesis that the peak position shift is only due to film’s strain.…”

Mechanical, Corrosion and Biological Properties of Room-Temperature Sputtered Aluminum Nitride Films with Dissimilar Nanostructure

“…When the deposition temperature is lower, the ad-atoms arriving at the substrate surface have reduced traverse mobility which impedes a high ordering and texturing of the growing AlN film. Usually, in such situations poorly or non-textured films are obtained [ 74 , 75 ]. The FWHM value of the RC obtained in the case of S4 samples (i.e., ~4.5°) is consistent with the ones obtained at a similar deposition temperature by Akiyama et al [ 73 ] or Yarar et al [ 76 ].…”