Ceramic fibers and grids of controlled geometry and composition were fabricated by electron beam evaporation of Al2O3 onto substrates patterned by optical lithography. The fibers were 4 and 5μm wide by 1μm thick. In addition, mixed metal oxide films from 0 to 10at% Ti, Zr, or Cr were produced by coevaporation with Al2O3. The compositions of the films were determined by Rutherford Backscattering Spectroscopy. TEM and electron diffraction examination showed all the films to be amorphous in structure.
The Al2O3 fibers had tensile strengths between 143 and 168 ksi and the Al2O3 film had a microindentation hardness of 8.4 GPa. Films with ≈ 1at% additions of Zr, Ti, and Cr had hardnesses of 11.0, 9.7, and 8.8 GPa respectively. The hardness then decreased with higher Zr, Ti, and Cr concentrations