No abstract

Recently, a wide range of new applications of diamond materials such as spintronics, field emission, and bio-sensing have been proposed. These applications often require the precise patterning of diamonds, which is not trivial because diamonds are the hardest materials known in nature. Among various patterning techniques, the focused ion beam milling method has been proven to provide flexibility as well as high resolution in the pattern design. In this study, a focused beam of 30 kV Ga + ions was utilized to create sub-micrometer size patterns out of crystalline diamonds. The sputtering rate, re-deposition, and surface roughening of diamond structure have been closely monitored with various milling parameters during the milling process. Our study revealed a low milling yield of 0.02 m 3 /nC, high Ga content re-deposition, and the formation of sub-micron scale terracing on the sidewall of patterned diamonds.

Focused ion beam (FIB) milling of diamonds has been investigated in various ways to create desired structures on diamonds, but not much research has been reported on the effects of crystal orientation, i.e. {100}, {110} and {111} of diamonds on FIB milling. In our previous work, it was noted that focused ion beam milling may develop preferred etched directions related to the crystal orientation of crystalline diamonds. In order to further investigate the phenomenon, a focused beam of 30 kV Ga+ ions was utilized to generate various patterns on different crystallographic planes of single crystalline diamonds. The morphology of milled patterns has been monitored with various ion currents to find the relationship between crystal orientations of diamonds and their impacts on FIB milled patterns. The work showed significant differences in deformation among different crystal orientations of the single crystal diamond, and the largest area of milling in {111} crystallographic planes.