Al2O3 single-crystalline substrates for optoelectronic applications

This paper reports on controlled electric and optical properties of single crystalline sapphire for substrates use. The crystals were grown by the Czochralski method from a graphite crucible by using an original non-conventional crystal growth assembly. We paid a special attention to the homogeneity of the crystal. A new model for the electric conduction mechanisms is considered, the validity of which was confirmed by experimental measurements.