Synthesis of diamond on substrate with mechanical treatment by RF plasma CVD method

Abstract

Two methods of treatment on Si substrate surface were attempted to investigate the effect of mechanical treatment on the substrate surface in the process of diamond nucleation by the RF plasma CVD method. In the first method, a great number of defects were made on the Si substrate surface by mechanical treatment using SiC powders. A large diamond particle was grown on a defect, and many small diamond particles were grown around it. In the second method, the Si substrate was bent by deposition of an a-C:H film on the back side of the substrate. For bending angles less than 18 degrees , the number density of diamond particles was almost constant and of the order of 106 cm-2. When the bending angle increased, the density tended to increase until an order of 107 cm-2 was attained. The formation of a SiC intermediate layer between the diamond phase and the Si substrate was confirmed for large bending angles (more than 18 degrees ).