Analysis of Cost: CVD Diamond Deposition and Finishing

This report describes several methods for polishing CVD diamond films, which can be applied separately or in conjunction with each other. These technologies are shown in Figure 1. From industry interviews, IBIS determined that the required surface roughness for the subsequent metallization operation is on the order of 0.1 microns, and polishing operations must be chosen to meet this specification while maximizing material removal rates. According to the experts surveyed, conventional abrasive lapping still remains the prevalent technology for polishing CVD diamond films, although Hot Iron Polishing, Reactive Plasma, and Ion Milling approaches have been considered. The IBIS technical Cost Model, therefore, assumes only abrasive lapping as the finishing operation, but allows exploration into other technologies. In general, the polishing rate attained with each technology depends greatly on the quality of the deposited diamond films, as measured by the original flatness and surface roughness. The chemical state of the diamond films, with respect to amorphous carbon content and doping levels, can also influence the polishing rate significantly.