It was shown that atomic hydrogen from a specially designed atomic beam source was well suited for removing chemisorbed oxygen from an fcc Co(110) film that was grown on a Cu(110) substrate using oxygen as a surfactant. Exposing the oxygen-terminated Co surface to atomic hydrogen led to a surface reaction which destroys the (3 x 1) ordered-O induced surface reconstruction of the Co film. Upon annealing at 380K, the hydrogen remaining on the O-free Co surface could be completely desorbed. With this technique, it was possible for the first time to prepare about 15 monolayers thick, atomically-flat fcc Co(110) films.

How to use Oxygen and Atomic Hydrogen to Prepare Atomically Flat FCC Co(110) Films. C.Tölkes, R.David, K.G.Tschersich, G.Comsa, P.Zeppenfeld: Europhysics Letters, 1999, 46[5], 589-94