Abstract: Dark features in diamond films prepared by DC arc plasma jet method were investigated by a laser marking process and fixed-point characterization. Optical microscopy, laser confocal scanning microscopy, scanning electron microscopy and electron backscattering diffraction methods were employed to analyze the defects at the same point. The results indicated that the dark features were such a kind of defects that embody pores and poor quality diamond phase located at grain boundaries of diamond films. The formation of the defects is related with the growth environment of the diamond films at specific grain boundaries.

Key words: Dark features in diamond films prepared by DC arc plasma jet method were investigated by a laser marking process and fixed-point characterization. Optical microscopy, laser confocal scanning microscopy, scanning electron microscopy and electron backscattering diffraction methods were employed to analyze the defects at the same point. The results indicated that the dark features were such a kind of defects that embody pores and poor quality diamond phase located at grain boundaries of diamond films. The formation of the defects is related with the growth environment of the diamond films at specific grain boundaries.