Abstract: A multilayer mirror (M) reflecting extreme ultraviolet (EUV) radiation from a first wavelength range in an EUV spectral region includes a substrate (SUB) and a stack of layers (SL). The stack of layers has layers having a low index material and layers having a high index material. The low index material has a lower real part of the refractive index than does the high index material at a given operating wavelength in the first wavelength range. The stack of layers also includes a spectral purity filter on the stack of layers. The spectral purity filter is effective as an anti-reflection layer for ultraviolet (UV) radiation from a second wavelength range in a UV spectral region to increase an EUV-UV-reflectivity ratio of the multilayer mirror. The spectral purity filter (SPF) includes a non-diffractive graded-index anti-reflection layer (GI-AR) effective to reduce reflectivity in the second wavelength range.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecting from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecting from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecting from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.

Abstract: A method for forming a hollow microneedle structure includes processing the front side of a wafer to form at least one microneedle projecting from a substrate and a through-bore passing through the microneedle and through a thickness of the substrate. An entire length of the through-bore is formed by a dry etching process performed from the front side of the wafer. Most preferably, upright surfaces of the microneedle structure and the through bore of the structure are formed by dry etching performed via a single mask with differing depths obtained by harnessing aspect ratio limitations of the dry etching process.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecting from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecting from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.

Abstract: A method for producing microneedles. The method including disposing a first layer of a radiation sensitive polymer on to a working surface and selectively irradiating the first layer such that the first layer has at least one irradiated region and at least one non-irradiated region. The method also including developing the first layer so as to selectively remove one of the at least one irradiated region and the at least one non-irradiated region such that, at least part of at least one remaining region at least partially defines a form of at least part of a microneedle structure. A microneedle structure including a plurality of microneedles at least partially formed from a radiation sensitive polymer.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecing from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.

Abstract: A method for producing microneedles. The method including disposing a first layer of a radiation sensitive polymer on to a working surface and selectively irradiating the first layer such that the first layer has at least one irradiated region and at least one non-irradiated region. The method also including developing the first layer so as to selectively remove one of the at least one irradiated region and the at least one non-irradiated region such that, at least part of at least one remaining region at least partially defines a form of at least part of a microneedle structure. A microneedle structure including a plurality of microneedles at least partially formed from a radiation sensitive polymer.

Abstract: A method for processing a wafer to form a plurality of hollow microneedles projecting from a substrate includes forming, by use of a dry etching process, a number of groups of recessed features, each including at least one slot deployed to form an open shape having an included area and at least one hole located within the included area. The internal surfaces of the holes and the slots are then coated with a protective layer. An anisotropic wet etching process is then performed in such a manner as to remove material from outside the included areas while leaving a projecting feature within each of the included areas. The protective layer is then removed to reveal the microneedles.