TRAPPING LEVELS IN HYDROTHERMAL AND SOLUTION-GROWN BISMUTH TITANIUM-OXIDE

Deep trapping levels in Bi(12)Ti0(20) Obtained by top seeded solution growth and by the hydrothermal technique have been compared. This was undertaken as such levels directly influence the photorefractive behav ior of the material. It is found that the most predominant of the peak s revealed by thermally stimulated conductivity measurements represent s two rather than a single defect level and that the deeper of the two becomes more significant in hydrothermally grown material. One defect found in the solution pulled material is notably absent from that pro duced hydrothermally. The consequence of adding phosphorus doping and the manner in which it affects the deep levels has also been examined.