COMPRESSIVE STRESS-INDUCED FORMATION OF PREFERRED ORIENTATION IN GLASSY-CARBON FOLLOWING HIGH-DOSE C IMPLANTATION

Abstract

It is well established that ion irradiation of glassy carbon with energetic ions leads to the formation of a dense amorphous surface layer. In the present work we show using cross-sectional Tem that oriented graphite-like regions are formed within the implanted layer of glassy carbon implanted with 50 keV C ions at high doses. The preferred orientation is such that the sp2 bonded graphite-like sheets lie normal to the implanted surface. Stress measurements of the implanted material show the presence of a biaxial compressive stress. Thermodynamic calculations predict that a non-hydrostatic stress can result in preferred orientation in anisotropic materials such as graphite. The preferred orie..