In-vacuum scattered light reduction with cupric oxide surfaces for   sensitive fluorescence detection
  We demonstrate a simple and easy method for producing low-reflectivity surfaces that are ultra-high vacuum compatible, may be baked to high temperatures, and are easily applied even on complex surface geometries. Black cupric oxide (CuO) surfaces are chemically grown in minutes on any copper surface, allowing for low-cost, rapid prototyping and production. The reflective properties are measured to be comparable to commercially available products for creating optically black surfaces. We describe a vacuum apparatus which uses multiple blackened copper surfaces for sensitive, low-background detection of molecules using laser-induced fluorescence. 
Eric B. Norrgard, Nathan Sitaraman, John F. Barry, Daniel J. McCarron,   Matthew H. Steinecker and David DeMille
physics.ins-det cond-mat.mtrl-sci