The synthesis of Sm/sub 2/(Co,Fe,Zr)/sub 17/ high energy product, 16 to 30 MGOe, thick sputtered films

Sputtering methods have been developed that allow the synthesis of Sm/sub 2/(Co,Fe,Zr)/sub 17/-type films with thicknesses between 20 to 100 mu m that exhibit an in-plane static energy product on the order of 20 MGOe. To achieve the energy product range of interest it is necessary that the films exhibit crystallographic texturing such that the crystallite c-axes preferentially lie in the plane of the substrate. This requires that the films be directly crystallized onto heated substrates. It has been found necessary to precoat the sapphire substrates with a boundary layer of oxidized Al-Al/sub 2/O/sub 3/ to allow the films to be strongly adherent to the substrate. Films have been made for a very narrow range of sputtering conditions that exhibit no X-ray reflections that correspond to the presence of crystallites with c-axes skewed out of the film plane. It is also necessary that the films be deposited so as to prevent the formation of a noticeable columnar growth pattern. The presence of such a columnar growth pattern introduces porosity that lowers the effective magnetization value. Such high-energy product films are potentially useful for the fabrication of small-scale integrated electromagnetic components.<
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