Abstract

ABSTRACTHigh resolution cathodoluminescence (CL) spectroscopy and imaging have been performed in transmission electron microscopy (TEM) to analyze defects and impurities in polycrystalline diamond films grown by chemical vapor deposition (CVD) using a variety of gas mixtures, and oxyacetylene combustion flame synthesis (CFS). The combination of CL and TEM allows a direct correlation of film microstructure with the electronic structure due to defects. The CL was found to be very nonuniformly distributed on a submicron scale reflecting different spatial distributions of N, B and Si impurities and their correlations with microstructure. Band A CL due to closely-spaced donor-acceptor (D-A) pairs was correlated with dislocations in both CVD-grown and CFS material whereas band A from widely-separated D-A pairs was uniformly distributed in the films. CL from several different N-related point-type defects was observed and found to depend on the growth gases used, although no correlation with microstructure has been observed so far. A di-Si interstitial impurity, believed to arise from the Si substrate and reactor walls, was not correlated with any microstructure but varied greatly in concentration from grain to grain and from film to Film. In addition, both highly faulted and defect-free grains were found to emit no visible CL due to mid gap states.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.