Xe FIB Milling and Measurement of Amorphous Damage in Diamond

Microand nanomachining of diamond using focused ion beam (FIB) continues to generate interest in applications such as diamond anvil cells, photonic devices, micro-cantilevers and tools for imprinting applications [1,2]. However, the milling rate of diamond by FIB is approximate 4X slower when compared to silicon using 30 kV Ga FIB [3]. Recent instrumentation using PFIB technology and Xe ions offer increased milling rates because of their ability to deliver up to 30X more current compared to Ga FIBs. While the sputter rate of diamond using Ga and Xe differs only slightly (0.07 μm/nC [Ga] and 0.09 μm/nC [Xe]), the ability to use more current for micromachining will allow users to increase throughput significantly. Therefore, it is of interest to understand the amount of amorphous damage introduced into a sidewall of diamond. Previous results indicate that for a glancing angle ~0 degrees, up to 35 nm of amorphous damage is introduced by Ga FIB in single crystal diamond [4].