Structural Peculiarities of As-Grown Single Crystals of Boron-Doped Diamond

Single crystals of boron-doped diamond grown by the temperature gradient method are studied by high-resolution transmission electron microscopy. It is established that boron is unevenly distributed in the diamond crystals. The diamond lattice contains fragments with a slightly increased interplanar spacing d111 equal to 0.207–0.208 nm as well as fragments with a distorted lattice. The introduction of boron into the lattice also leads to the formation of “spacing faults” consisting of several layers with the interplanar spacing increased from 0.206 to about 0.25 nm. This is explained by the presence of boron atoms in these regions weakening the lattice, which, in turn, leads to the partial breakage of sp3 bonds.