Abstract: In general, in one aspect, the invention features a method that includes forming layer of a mask material on a surface of a first layer, patterning the layer of the mask material to obtain a mask feature, the mask feature having a surface comprising a depression, inducing mass transport of the mask material of the mask feature to obtain a modified mask feature, and transferring a profile of the modified mask feature into the first layer to form a first structure. In general, in another aspect, the invention features a method that includes forming layer of a mask material on a surface of a first layer, patterning the layer of the mask material to obtain a mask feature, inducing mass transport of the mask material of the mask feature to obtain a modified mask feature, and transferring a profile of the modified mask feature into the first layer to form a first structure.

Abstract: Methods for forming a metal grating include providing a first grating including a plurality of grating lines formed from a dielectric material, each grating having a pair of sidewalls, facing sidewalls of adjacent grating lines being separated by corresponding trenches, the grating lines and trenches forming a grating surface; forming a layer of a metal on the grating surface, where the metal layer has a constant thickness and conforms to the grating surface; and removing portions of the metal layer between sidewalls of adjacent grating lines of the first grating to form a metal grating having grating lines formed from the metal, the grating lines of the metal grating corresponding to the portions of the metal layer adjacent the sidewalls of the grating lines of the first grating. The metal grating has a pitch of 200 nm or less, a depth of 50 nm or more, and the grating lines of the metal grating have an aspect ratio of 10-to-1 or more.

Abstract: In general, in one aspect, the invention features an apparatus that includes a plurality of optical elements arranged to form an image of an object. The elements include a first element comprising one or more regions of a polarizing material, the regions being shaped as one or more visual features, a polarizer, and a mounting assembly including a first mount for the first element and a second mount for the polarizer. At least the first or second mount is rotatable with respect to an optical axis between a first orientation and a second orientation. In the first orientation, the visual features are visible in the image of the object and, in the second orientation, the visual features are not visible in the image of the object.

Abstract: In general, in one aspect, the invention features a method that includes forming layer of a mask material on a surface of a first layer, patterning the layer of the mask material to obtain a mask feature, the mask feature having a surface comprising a depression, inducing mass transport of the mask material of the mask feature to obtain a modified mask feature, and transferring a profile of the modified mask feature into the first layer to form a first structure. In general, in another aspect, the invention features a method that includes forming layer of a mask material on a surface of a first layer, patterning the layer of the mask material to obtain a mask feature, inducing mass transport of the mask material of the mask feature to obtain a modified mask feature, and transferring a profile of the modified mask feature into the first layer to form a first structure.

Abstract: In general, in one aspect, the invention features an apparatus that includes a plurality of optical elements arranged to form an image of an object. The elements include a first element comprising one or more regions of a polarizing material, the regions being shaped as one or more visual features, a polarizer, and a mounting assembly including a first mount for the first element and a second mount for the polarizer. At least the first or second mount is rotatable with respect to an optical axis between a first orientation and a second orientation. In the first orientation, the visual features are visible in the image of the object and, in the second orientation, the visual features are not visible in the image of the object.

Abstract: Methods for forming a metal grating include providing a first grating including a plurality of grating lines formed from a dielectric material, each grating having a pair of sidewalls, facing sidewalls of adjacent grating lines being separated by corresponding trenches, the grating lines and trenches forming a grating surface; forming a layer of a metal on the grating surface, where the metal layer has a constant thickness and conforms to the grating surface; and removing portions of the metal layer between sidewalls of adjacent grating lines of the first grating to form a metal grating having grating lines formed from the metal, the grating lines of the metal grating corresponding to the portions of the metal layer adjacent the sidewalls of the grating lines of the first grating. The metal grating has a pitch of 200 nm or less, a depth of 50 nm or more, and the grating lines of the metal grating have an aspect ratio of 10-to-1 or more.

Abstract: Single-walled carbon nanotube transistor and rectifying devices, and associated methods of making such devices include a porous structure for the single-walled carbon nanotubes. The porous structure may be anodized aluminum oxide or another material. Electrodes for source and drain of a transistor are provided at opposite ends of the single-walled carbon nanotube devices. A gate region may be provided one end or both ends of the porous structure. The gate electrode may be formed into the porous structure. A transistor of the invention may be especially suited for power transistor or power amplifier applications.

Abstract: Solutions permit or facilitate faster and/or easier processing involving loading or unloading of a work module into a process station. For example, the work module may be a processing tube or the like and the process station may be a heating station such as a tube furnace or the like. In one embodiment, the loading is from a single side of a process station. In one embodiment, the work module includes inlets and outlets for fluid flow, with both inlets and outlets being closer toward one side of the work module than the other side.

Abstract: A field emission device having bundles of aligned parallel carbon nanotubes on a substrate. The carbon nanotubes are oriented perpendicular to the substrate. The carbon nanotube bundles may be up to 300 microns tall, for example. The bundles of carbon nanotubes extend only from regions of the substrate patterned with a catalyst material. Preferably, the catalyst material is iron oxide. The substrate is preferably porous silicon, as this produces the highest quality, most well-aligned nanotubes. Smooth, nonporous silicon or quartz can also be used as the substrate. The method of the invention starts with forming a porous layer on a silicon substrate by electrochemical etching. Then, a thin layer of iron is deposited on the porous layer in patterned regions. The iron is then oxidized into iron oxide, and then the substrate is exposed to ethylene gas at elevated temperature. The iron oxide catalyzes the formation of bundles of aligned parallel carbon nanotubes which grow perpendicular to the substrate surface.

Abstract: In some embodiments of the invention, there is a method or apparatus for tight sealing between a first space and a second space. The second space is at least partially enclosed by a member. The method or apparatus includes or performs the step of creating or maintaining a pressure difference between a pressure in a third space at a seal assembly and pressure in each of the first space and the second space; and pushing, caused by the pressure difference, against a seal in the seal assembly to tighten sealing provided by the seal.

Abstract: In one embodiment, an apparatus for fabricating nanostructure-based devices on workpieces includes: a stage for supporting a workpiece, a radiating-energy source, and a feedstock delivery system. The workpiece has catalyst thereon. The radiating-energy source is configured to focus radiating energy toward a work region of the workpiece to directly heat catalyst at the work region, without directly heating catalyst at one or more other work regions of the workpiece. The feedstock delivery system delivers feedstock gas to the catalyst at the work region. The feedstock delivery system includes a feedstock heating system. The feedstock heating system is configured to heat the feedstock gas not merely by any global heating of the chamber or any direct excitation of gas over the work region by the focused radiating energy. Preferably, the radiating-energy source emits multiple prongs of radiating energy.

Abstract: In one embodiment, an apparatus for fabricating nanostructure-based devices on a workpiece includes: a stage for supporting a workpiece, a radiating-energy source, and a feedstock delivery system. The workpiece has catalyst deposited thereon. The workpiece includes multiple work regions (e.g., dies). The feedstock delivery system is for delivery of feedstock gas to said catalyst. The feedstock delivery system is configured to directly heat catalyst on at least one die via simultaneously emitted multiple prongs of radiating energy. Preferably, the feedstock delivery system includes a feedstock heating system that is configured to heat the feedstock gas not merely by any global heating of a chamber containing the work region or any direct excitation of gas over the work region by the radiating energy.

Abstract: A field emission device having bundles of aligned parallel carbon nanotubes on a substrate. The carbon nanotubes are oriented perpendicular to the substrate. The carbon nanotube bundles may be up to 300 microns tall, for example. The bundles of carbon nanotubes extend only from regions of the substrate patterned with a catalyst material. Preferably, the catalyst material is iron oxide. The substrate is preferably porous silicon, as this produces the highest quality, most well-aligned nanotubes. Smooth, nonporous silicon or quartz can also be used as the substrate. The method of the invention starts with forming a porous layer on a silicon substrate by electrochemical etching. Then, a thin layer of iron is deposited on the porous layer in patterned regions. The iron is then oxidized into iron oxide, and then the substrate is exposed to ethylene gas at elevated temperature. The iron oxide catalyzes the formation of bundles of aligned parallel carbon nanotubes which grow perpendicular to the substrate surface.

Abstract: A field emission device having bundles of aligned parallel carbon nanotubes on a substrate. The carbon nanotubes are oriented perpendicular to the substrate. The carbon nanotube bundles may be up to 300 microns tall, for example. The bundles of carbon nanotubes extend only from regions of the substrate patterned with a catalyst material. Preferably, the catalyst material is iron oxide. The substrate is preferably porous silicon, as this produces the highest quality, most well-aligned nanotubes. Smooth, nonporous silicon or quartz can also be used as the substrate. The method of the invention starts with forming a porous layer on a silicon substrate by electrochemical etching. Then, a thin layer of iron is deposited on the porous layer in patterned regions. The iron is then oxidized into iron oxide, and then the substrate is exposed to ethylene gas at elevated temperature. The iron oxide catalyzes the formation of bundles of aligned parallel carbon nanotubes which grow perpendicular to the substrate surface.