As-grown single crystals which were synthesized using high temperatures and high pressures, in the presence of a FeNi catalyst, were examined by using scanning electron microscopy and transmission electron microscopy. Pits on the (111) surface were generated by emerging screw dislocations, and were revealed by electrolytic etching. These were used to study the motion of dislocations under the action of an applied stress. Stacking-fault tetrahedra and stacking faults were investigated by using moiré imaging methods. The stacking-fault tetrahedra and stacking faults were suggested to arise from supersaturated vacancies that were generated during rapid cooling from high temperatures. Dislocation networks, and an array of parallel dislocations, were directly examined by means of transmission electron microscopy and were related to thermal stresses which were caused by inclusions.

Observation of Etch Pits and Defects in Diamond Single Crystals Prepared under High Temperature-High Pressure. L.W.Yin, M.S.Li, D.S.Sun, Z.Y.Hao, F.Z.Li, Z.Y.Yao: Materials Science and Engineering A, 2001, 315[1-2], 108-12