A method of forming an undercut microstructure includes: forming an etch mask on a top surface of a substrate; forming, on a top surface of the etch mask, an ion implantation mask having a top surface that is smaller than the top surface of the etch mask and that does not extend beyond the top surface of the etch mask; ion implanting the substrate in the presence of the etch mask and the ion implantation mask so that a damaged region is generated at a depth below an area of the surface that is not masked by the ion implantation mask; and etching the surface of the substrate until the damaged region is removed.