Influence of Surface Ultrasonic Scratching Pretreatment on Diamond Nucleation

Influence of the surface ultrasonic scratching pretreatment on diamond nucletion has been studied.Diamond films have been deposited on Si(100) by hot-filament chemical vapour deposition and characterized by scanning electron microscopy. 1.5~40μm diamond powders and mixtures of 1.5~5μm diamond as well as 5~20μm TaC powders were used in the ultrasonic scratching pretreatment. The experiment results show that the diamond nucleation density increases with increment of diamond powders size, and a mixture of diamond and TaC powders enhances diamond nucleation much more greatly than that of diamond powders alone, especially when the size of diamond powdets is not very large.