Yb. Xia et al., Surfaces of undoped and boron doped polycrystalline diamond films influenced by negative DC bias voltage, DIAM RELAT, 9(9-10), 2000, pp. 1636-1639
The hydrogen ion bombardment is performed by applying a negative bias volta
ge to the substrate during microwave plasma chemical vapor deposition proce
ss, using only hydrogen as reactant gas. The size of (001) faces increases
after hydrogen ion etching while other grains are etched off. The surfaces
of [001]-oriented films after doping boron are investigated by scanning ele
ctron microscopy (SEM) and cathodoluminescent (CL) spectra. The absence of
the band-A emission in the CL spectra means a low density of dislocation in
the films. It is the first time that the peak at 741.5 nm and the broad pe
ak at approximately 575 and 625 nm in the CL spectra were reduced efficient
ly after boron doping in (001) polycrystalline diamond films and to propose
that these phenomena should be explained in simple terms with penetration
of the lattice nets of the [001]-oriented faces model. (C) 2000 Elsevier Sc
ience S.A. All rights reserved.