National Synchrotron Light Source Seminar

In spite of the widely recognized importance of WSi2/Si multilayer coatings for X-ray nanofocusing [1, 2], little work has been done to explore the different possibilities to prepare Multilayers Laue Lenses (MLL) from the as-grown films. The current technique to section the multilayers [3] is based on TEM cross-section like preparation. Despite the good results provided by this method, it has the disadvantage of being highly time and material consumptive, as well as imparting mechanical stress on the MLLs being sectioned which leads to a very poor yield rate and inherent limitation on sectioning thickness for the latest MLLs which have an unprecedented growth thickness. Reactive ion etching is actively being explored as a technique of choice to achieve a high-quality sectioning of the multilayers with preservation of the as-grown qualities of the samples. In addition, this preparation technique would provide access to more exotic shapes, which may provide greater mechanical stability of the MLL during actual use in synchrotron applications. This presentation will discuss the growth of multilayers, the associated metrology controls and our recent experimental investigations on reactive ion etching and inductively coupled plasma reactive ion etching of WSi2/Si multilayers [4] to fabricate usable Multilayer Laue lenses.