Cathodoluminescence of diamond films grown on pretreated Si(001) substrates by microwave plasma chemical vapour deposition

Diamond films were grown on a.c. bias-enhanced nucleated Si(001) wafers using different CH4 concentrations by microwave plasma chemical vapour deposition. Cathodoluminescence (CL) spectra from the films exhibit emission components which are associated with defects such as neutral atomic vacancies, nitrogen-vacancy complexes and structural defects such as dislocations. The luminescence intensities of the related peaks were found to depend on the BEN and CH4 concentrations. Comparison of the CL and SEM images indicates that a nitrogen-associated defect is primarily distributed in the {001} growth facets of the diamond grains. However, the structural defect-related centres are found to be located mainly near grain boundaries and {111} growth facets. (C) 1999 Elsevier Science S.A. All rights reserved.