Dislocation electrical conductivity of plastically deformed natural diamonds

The temperature dependence of the electrical conductivity of natural semiconducting diamonds of Ic type has been studied. The activation energies of the dislocation acceptor centers (induced by plastic deformation) are found to be ɛ3 = 0.29–0.36 eV. Four natural diamonds of IIa type with a resistivity of 1015–1016 Ω cm were plastically deformed to prove the formation of levels with the activation energy ɛ3 in semiconducting diamonds. The deformation led to a decrease in resistivity by one to two orders of magnitude and to the formation of a new level with ɛ3 = 0.29 eV, which is characteristic of semiconducting diamonds. We expect deformation to induce dislocation centers, not only in Ic-type diamonds, but also in natural semiconducting diamonds of IIb type.