FABRICATION OF FREESTANDING DIAMOND MEMBRANES

We describe here a method for fabricating free-standing diamond membra nes. Diamond films were deposited on a silicon substrate by microwave plasma-assisted chemical vapor deposition and then part of the substra te chemically removed. The films described here were 15 mm in diameter with thickness of approximately 12 mu m. A novel feature of our appro ach lies in the method used to obtain the selective dissolution of the substrate; a container with O-rings was used, instead of masks, allow ing a fast and clean isotropic dissolution of part of the silicon subs trate. The deposited diamond films as well as the free-standing membra nes were characterized by scanning and transmission electron microscop y, electron diffraction and Raman spectroscopy.