Highly boron-doped diamond films were deposited on porous titanium substrates by hot filament chemical vapor deposition technique.The morphology variation of highly boron-doped diamond films grown on porous titanium substrates was investigated,and the effects of carbon concentration on nucleation density and diamond growth were also studied.The continuous change of surface morphology and structure of diamond film were characterized by scanning electron microscopy.The structures of diamond film and interlayer were analyzed by X-ray diffraction.The quality of boron-doped diamond film was confirmed by visible Raman spectroscopy.The experimental results reveal that surface morphology and quality of boron-doped diamond films are various due to the change of carbon concentration.The thickness of intermediate layer decreases with the carbon concentration increasing.
Diamond films are deposited on porous Ti substrates by hot filament chemical vapor deposition (HFCVD) method. For adjusting the residual stress of substrate and the titanium carbide (TiC) intermediate layer, the substrates are under annealing process firstly, then are put into alkaline solution with electricity oxidation, and finally composite membranes are obtained by HFCVD, which are characterized by X-ray diffraction (XRD), metalloscope and scanning electron microscope (SEM). Results show that the composite membranes deposited on unannealed substrates are cracked obviously in both sides and broken off easily. After annealing process, the membranes are no longer cracked easily, because the tensile stress distributed in substrates is significantly relieved. After passivation process, TiC generated between diamond film and substrate is less than that without passivation process.
