Development of the Technique for Fabricating Submicron Moire Gratings on Metal Materials Using Focused Ion Beam Milling

A focused gallium ion (Ga+) beam is used to fabricate micro/submicron spacing gratings on the surface of porous NiTi shape memory alloy (SMA). The crossing type of gratings with double-frequency (2500l/mm and 5000l/mm) using the focused ion beam (FIB) milling are successfully produced in a combination mode or superposition mode. Based on the double-frequency gratings, high-quality scanning electron microscopy (SEM) Moire patterns are obtained to study the micro-scale deformation of porous NiTi SMA. The grating fabrication technique is discussed in detail. The experimental results verify the feasibility of fabricating high frequency grating on metal surface using FIB milling.