| 摘要 |
<p>A sputtering target (176) has a sputtering surface with first and second regions (208, 206) of respective first and second materials. The first region (208) comprises a surface of a first member (208) of the first material, such as a circular cobalt plate. The second region (206) comprises a surface of second member (206) of the second material, such as a platinum ring. A cobalt cover ring (210) clamps the platinum ring (206) to the cobalt plate. By varying the relative sizes of the first and second regions (208, 206) as by changing the size of the cover ring (210) to expose more or less of the platinum ring (206), the concentration of the two materials in a layer deposited from the target (176) onto substrates (260) is varied. In addition, by imparting planetary motion to substrates (260) during deposition and sizing and positioning the exposed portion of the platinum ring (206) a radial coercivity gradient is established in the layer deposited on the substrates (260).</p> |
