Study of defects in CVD and ultradisperse diamond

Characterization of defects in chemical vapor deposition (CVD) and detonati on synthesis ultradisperse diamond (UDD) is reported. Electron Spin Resonan ce, Raman, and photothermal deflection spectroscopies show that sp(2)-bonde d carbon is a dominant defect in UDD diamond. Although UDD was made from tr initrotoluene, no substitutional nitrogen was detected. Photoluminescence ( PL) from CVD films showed narrow lines at 1.68, 1.945 and 2.156 eV, in addi tion to broad red and green bands, while only a blue band was observed in U DD samples. On the basis of PL excitation measurements, the green band in C VD diamond is attributed to donor-acceptor pair recombination. On the basis of a spatial variation of PL intensity in CVD films, the incorporation mec hanism for silicon, nitrogen, and boron atoms is discussed. The Manuscript Prime Novelty statement: It is shown that sp(2) carbon is a dominant defect in diamond obtained by detonation technique from trinitroto luene, while no substitutional nitrogen was detected. The green band in CVD diamond is proved to originate from donor-acceptor pair recombination. (C) 1999 Elsevier Science S.A. All rights reserved.