In this work we present sputtered multicomponent dielectrics based on mixtures of HfO2 and SiO2. This way it is
possible to get stable amorphous structure up to 800ºC, that does not happen for pure HfO2, for instance, that present a
polycrystalline structure when deposited without any intentional substrate heating. Besides, also the band gap of the
resulting films is increased when compared with pure HfO2 that theoretically is an advantage in getting a suitable band
offset with the semiconductor layer on oxide TFTs. Concerning the electrical characterization, the leakage current on c-Si
MIS structures is low as 10-9 Acm-2 at 10 V. The amorphous structure of the films also lead to better
dielectric/semiconductor interfaces, as suggested by C-V characteristics on GIZO MIS structures, which do not present
strong variation with frequency. On other hand, the dielectric constant decreases due to the incorporation of SiO2 and
Al2O3. Further improvement on insulating and interface characteristics is achieved using multilayer stacks and substrate
bias during deposition.
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