ION BEAM POLISHING FOR ULTRA-SHARP DIAMOND BLADES

A PREREQUISITE FOR DIAMOND KERATOTOMY BLADES IS THAT THEY BE EXTREMELY SHARP. THIS PRESENTS A PROBLEM, SINCE POLISHING THESE INSTRUMENTS IS DIFFICULT AND TIME CONSUMING. CONVENTIONAL MECHANICAL POLISHING TYPICALLY PRODUCES A TIP WIDTH OF 1 MICRON OR GREATER, WHEREAS A TIP WIDTH OF LESS THAN 0.5 MICRONS IS DESIRABLE. ANOTHER PROBLEM IS THAT THE NON-REPEATABILITY OF THE POLISHING PROCESS CAUSES VARIATION IN BLADE SHARPNESS FROM BLADE-TO-BLADE AND FROM LOT-TO-LOT. WE HOPE TO DEVELOP A NOVEL METHOD OF POLISHING DIAMONDS, ION BEAM SPUTTER POLISHING. BY EXPOSING DIAMOND BLADES TO AN ENERGETIC STREAM OF IONS, IT WILL BE POSSIBLE TO RELIABLY AND REPEATABLY POLISH THE BLADES TO VERY SMALL TIP DIMENSIONS (PRELIMINARY STUDIES HAVE SHOWN THAT TIP WIDTHS AS SMALL AS 20-30 NONOMETERS CAN BE ACHIEVED). IN PHASE I A MATRIX OF ION BEAM BOMBARDMENT CONDITIONS WILL BE EXPLORED TO DEVELOP OPTIMIZED PARAMETERS. SPECIFICALLY, THE EFFECTS OF ION ENERGY, ION SPECIES, ION ANGLE OF INCIDENCE, AND DURATION OF ION BEAM BOMBARDMENT ON POLISHING EFFICIENCY WILL BE EXPLORED. PHASE II WILL REFINE THE PROCESS, MAKING IT VIABLE ON A COMMERCIAL SCALE.