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 usi ng different CH4 concentrations by microwave plasma chemical vapour deposit ion. Cathodoluminescence (CL) spectra from the films exhibit emission compo nents which are associated with defects such as neutral atomic vacancies, n itrogen-vacancy complexes and structural defects such as dislocations. The luminescence intensities of the related peaks were found to depend on the B EN and CH4 concentrations. Comparison of the CL and SEM images indicates th at a nitrogen-associated defect is primarily distributed in the {001} growt h facets of the diamond grains. However, the structural defect-related cent res are found to be located mainly near grain boundaries and {111} growth f acets. (C) 1999 Elsevier Science S.A. All rights reserved.