Fabrication of Ultrathin Single-Crystal Diamond Membranes
  We demonstrate the fabrication of sub-micron layers of single-crystal diamond suitable for subsequent processing as demonstrated by this test ring structure. This method is a significant enabling technology for nanomechanical and photonic structures incorporating colour-centres. The process uses a novel double implant process, annealing and chemical etching to produce membranes of diamond from single-crystal starting material, the thinnest layers achieved to date are 210 nm thick. 
B. A. Fairchild, P. Olivero, S. Rubanov, A. D. Greentree, F.   Waldermann, R. A. Taylor, I. Walmsley, J. M. Smith, S. Huntin...
cond-mat.mtrl-sci