| Popis: |
The second part of this thesis work was dedicated to extending the applicability of the ETP-MOCVD technique to obtain dense Al2O3 films at relatively low substrate temperatures (4% of the film thickness. By decreasing the pressure from 1.5 mbar to 0.38 mbar ("low pressure"), the initial layer becomes denser, the sheet resistance gradient is significantly reduced and the films become smoother, i.e., 30 at%), a key parameter to obtain film densification was identified. Through the addition of ion bombardment to the ETP-MOCVD process by means of an external rf bias applied to the substrate, films with high refractive index (1.6 at 633 nm) and low hydrogen content (=4%) can be obtained at temperatures even below 150 ºC. These films are potentially suitable as water permeation barrier layers on polymers, as preliminary investigations have already indicated. |
