Abstract: The hydrogen and boron ion bombardments were performed by applying a negative bias voltage to the substrate during microwave plasma chemical vapor deposition process. The size of (001) faces increased after hydrogen ions etching while other grains were etched off by using only hydrogen as reactant gas. The 001-oriented films after boron doping were investigated by scanning electron 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 to indicate that the peak at 741.5 nm and the broad peak at around 575 nm and 625 nm in the CL spectra are reduced efficiently after boron doping in (001) polycrystalline diamond films. These phenomena should be explained in simple terms with a penetrating or being adsorbed by the lattice nets of 001-oriented film model.