THE UHV DEPOSITION OF SHORT-PERIOD MULTILAYERS FOR X-RAY MIRROR APPLICATIONS

We have used ultra-high vacuum dc magnetron sputtering to deposit a series of multilayers onto silicon substrates at either 50 or -90-degrees-C. The multilayers have Si as the light element and one of W, Hf, Mo or Pt as the heavy element, with modulation periods between 13 and 40 angstrom. We compare multilayers deposited at the two temperatures and discuss the problems of re-sputtering and intermixing, together with the more general issues of interface profiles and materials considerations for the optimisation of such multilayers.