A cathodoluminescence study of boron doped {l l l}-homoepitaxial diamond films

摘要

In this work we use cathodoluminescence (CL) at liquid helium temperature to investigate the boron incorporation in {1 1 1 }-homoepitaxial diamond films, grown outside the visible plasma ball by the Microwave plasma-assisted chemical vapor deposition (MPCVD) technique. The boron concentration of this set of films covers the whole possible doping range divided into four parts: Low doping (5 × l0~(l6)<[B]2 × l0~(21) cm~(-3)). The phase separation occurs for very high boron concentrations, between the diamond phase (sp~3 carbon) and the other components of the layer, namely sp~2 carbon and boron. A part of them is accumulated outside the diamond lattice. This detailed cathodoluminescence investigation of {1 l l}-homoepitaxial diamond films has led to determining the doping range of the films and following the evolution of their crystalline quality when the boron concentration increases. In addition, a comparison between {111} and {100} films in the same doping ranges has been undertaken.