Relationship between grain boundaries and broad luminescence peaks in CVD diamond films

摘要

Broad luminescence bands have been frequently observed by micro-photoluminescence (PL) spectroscopy of bulk samples of polycrystalline CVD diamond films; however, no definitve explanation exists for them at present. In an attempt to clarify the situation, a successful method for correlating TEM images with micro-PL spectroscopy has been developed and some links between grain boundaries and broad-band luminescence have been found. The samples studied were polycrystalline B-doped (boron doping at approx= 10~(18) cm~(-3)) and unintentional N-doped (nominally undoped) CVD diamond films prepared for plan view TEM and analysed by micro-Pl spectroscopy.