TRAPPING MECHANISMS IN THE MONOCRYSTALLINE TITANIUM DIOXIDE: EFFECT OF ANNEALING AND TEMPERATURE

The present work deals with the study of the trapping mechanisms in the monocrystalline rutile (TiO2) as a function of the temperature and the annealing treatment. It is well known that the polishing of the material plays an important role in the trapping mechanisms according to the fact that defects can take place in. For this then, thermal treatments (annealing) has been performed in order to modify these created defects and to show how could be their action on the trapping mechanisms. The tests of trapping phenomena have been realised by using the Scanning Microscope Mirror Method Effect (SEMME) as a method of characterisation. The experiments carried out have shown that monocrystalline rutile traps a strong quantity of electric charges. The results reveal the localisation of electric charges on sample which has been annealed for a long time contrary for non annealed samples. The mirrors are elliptic and confirm the problem of the electric charges spreading connected to the crystallographic orientation and the nature of extended defects. In the fundamental point of view, the anisotropy of the material could play an important role on the trapping mechanisms.