Ion irradiation and reduction effect on the conductivity of heavily MgO + Fe/sub 2/O/sub 3/-doped LiNbO/sub 3/ single crystals

The effect of the insulator-conductor transition of surface layers of oxides by ion bombardment was investigated by the example of doped LiNbO/sub 3/ single crystals. The important role of reduction in modification of conducting properties of the ion-irradiated crystals was established. The action of reduction on the electric characteristics of crystals LiNbO/sub 3/ is similar to that of ion bombardment A new band of optical absorption with a maximum at 3.7 eV caused by presence of Mg impurity in LiNbO/sub 3/+ MgO was founded. The comparative analysis of electric properties of reduced and irradiated by Ar/sup +/ ions crystals shows, that conductivity of the lithium niobate ion-modified layers is carried out by polarons hopping.