Preparation method and RF behaviour of Nb/sub 3/Sn thin films obtained by bronze process

Aiming to application in RF devices, a method to obtain Nb/sub 3/Sn thin films, combining sputtering technique and bronze process, has been developed. A niobium film, 300-500 nm thick, is deposited by sputtering onto a 7 at.% tin bronze substratum. In order to allow the diffusion of tin into niobium and the formation of the A15 phase, the sample is maintained at about 700/spl deg/C during the deposition, and for several hours after the deposition. A Nb/sub 3/Sn film with very good adhesion on the substratum has been obtained. The RF behaviour of the film has been analyzed at about 10 GHz at temperature near Tc, using a host copper cavity having the top plate substituted with the bronze-Nb/sub 3/Sn sample. Both the quality factor and the frequency shift have been measured.<
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