Thin Film Diamond Polycrystalline CVD
Scientists and engineers can now exploit many of the outstanding properties of diamond, as CVD diamond films are a practical form for a number of applications. Thin films of polycrystalline diamond can be deposited onto a range of materials using CVD. Polycrystalline CVD diamond has been used in wear-resistant coatings, diamond-coated windows, diamond-coated wire and composites and cutting tools.
However, success in manufacturing diamond for gemstones or electronics has been far more elusive. Polycrystalline diamond does not possess all of the advantageous properties of Scio Diamond’s single- crystal diamond. Polycrystalline diamond is made up of many crystals at different orientations, resulting in “grain boundaries” that impede electronic performance and reduce light transmission.
Film roughness and crystal imperfections also severely limit the material’s use in many optical, electronic and other high-tech or high-precision applications. A film like that might make a fine abrasive coating, but most of the envisioned uses for diamond films (such as optics, thermal management, electronic devices, etc.) require that the diamond surface be as smooth as possible. In addition, the presence of grain boundaries in polycrystalline diamond destroys the function of optical and electronic devices. Polycrystalline diamond is also unsuitable for use as a gemstone for a number of reasons, most notably its lack of visual appeal. Scio Diamond’s single-crystal diamond has none of these challenges and produces beautiful high quality gemstones.
Nanocrystalline CVD Diamond
A relatively recent variation of CVD diamond, this method produces a film that is much smoother than polycrystalline film, but its mechanical and electrical properties are not as extreme. Nanocrystalline CVD diamond has shown excellent promise for the fabrication of very small mechanical structures for Microelectromechanical Systems (MEMS) applications but is not applicable in a broad range of applications where Scio’s single-crystal approach excels.