ENHANCED X-RAY OPTICAL CONTRAST OF MO SI MULTILAYERS BY H-IMPLANTATION OF SI/

To increase the x-ray optical contrast of Mo/Si multilayers, we study low energy hydrogen ion implantation of amorphous Si layers. Using ela stic recoil detection and Rutherford backscattering spectrometry, we m easure the result of hydrogen implantation on Si atomic density. We fi nd a lowering of Si atomic density, and, thus, an enhancement of x-ray optical contrast, as a result of H implantation. We find that the Si atomic density saturates at. a minimum of 64+/-5% of the crystalline v alue. We have also observed a minor smoothing effect of H+ ion bombard ment. Combined with Kr+ ion bombardment, causing a very much larger sm oothing of the Si surface, the atomic density is found to saturate at a minimum of 77+/-5% of the crystalline value. (C) 1996 American Insti tute of Physics.