Improving electro-optic window reliability with DIACER™ coatings

Most commercial diamond synthesis processes involve some form of chemical vapor deposition (CVD) which results in heterogeneous nucleation on the surface of window or dome materials. Generally, these processes have relatively long deposition times driven by the slow CVD kinetics. An alternate method called DIACER™ uses an aqueous seed crystal dispersion applied to the window substrates prior to CVD. These seed crystals reduce nucleation times and speed CVD deposition rates. Thicker coatings can be produced by repeating the seeding/CVD cycle until the required thickness is achieved. This paper will review DIACER™ coating results on silicon substrates. Scanning electron microscopy and atomic force microscopy images of the coatings will be presented. IR transmission results will be presented both before and after sand and rain erosion exposures. The results of this testing will show DIACER™ coatings to be durable for the protection of silicon substrates after exposure to severe sand environments.