Ion-Beam-Assisted Lift-Off Technique for Three-Dimensional Micromachining of Freestanding Single-Crystal Diamond

The machining of 3D microstructures in single‐crystal artificial diamond is demonstrated with a focused ion beam (FIB)‐assisted lift‐off technique. A sacrificial buried layer is created with MeV ion implantation, followed by patterning of selected regions with the FIB technique; the sacrificial layer is then selectively etched, leaving 3D free‐standing microstructures in the bulk (see Figure). Using this fabrication technique, light waveguiding through a microstructure in single‐crystal diamond is demonstrated for the first time.