Focused ion beam deposition of carbon for photomask repair

Abstract

Initial results from a series of experiments to study focused ion beam deposition (FIBD) of carbon from a hydrocarbon gas are reported. Deposition and resputtering are the competing processes which determine the overall growth rate of the carbon patch material in mask repair. Deposition and resputtering sensitivities have been measured for a range of hydrocarbon gas pressures and different scan strategies. There is evidence of pixel dose rate related effects associated with different scan strategies. A model for the deposition process has been developed, which is consistent with the results.