Abstract:
A spectral purity filter includes a substrate, a plurality of apertures through the substrate, and a plurality of walls. The walls define the plurality of apertures through the substrate. The spectral purity filter also includes a first layer formed on the substrate to reflect radiation of a first wavelength, and a second layer formed on the first layer to prevent oxidation of the first layer. The apertures are constructed and arranged to be able to transmit at least a portion of radiation of a second wavelength therethrough.
Abstract:
There is provided a multilayer mirror (80) comprising a layer of a first material (84) and a layer of silicon (82). The layer of the first material and the layer of silicon form a stack of layers. An exposed region of the layer of silicon comprises a modification that is arranged to improve the robustness of the exposed region of silicon.
Abstract:
There is provided a multilayer mirror (80) comprising a layer of a first material (84) and a layer of silicon (82). The layer of the first material and the layer of silicon form a stack of layers. An exposed region of the layer of silicon comprises a modification that is arranged to improve the robustness of the exposed region of silicon.