Abstract: A method of fabricating a single-crystal silicon photovoltaic cell includes providing a single-crystal silicon wafer and a structural support member. The single-crystal silicon wafer has a first major surface and a second major surface. Each major surface extends along a major surface plane. The single-crystal silicon wafer has a thickness greater than 100 micrometers and a dimension greater than 50 mm. The method further includes mounting the structural support member to the first major surface or to the second major surface. The method further includes reducing thickness of the single-crystal silicon wafer to a thickness less than or equal to 100 micrometers while the single-crystal silicon wafer is mounted to the structural support member. The method further includes providing the first major surface with a diffusion and a metalization grid and providing the second major surface with a back surface contact.

Abstract: A method of fabricating a single-crystal silicon photovoltaic cell includes providing a single-crystal silicon wafer and a structural support member. The single-crystal silicon wafer has a first major surface and a second major surface. Each major surface extends along a major surface plane. The single-crystal silicon wafer has a thickness greater than 100 micrometers and a dimension greater than 50 mm. The method further includes mounting the structural support member to the first major surface or to the second major surface. The method further includes reducing thickness of the single-crystal silicon wafer to a thickness less than or equal to 100 micrometers while the single-crystal silicon wafer is mounted to the structural support member. The method further includes providing the first major surface with a diffusion and a metalization grid and providing the second major surface with a back surface contact.

Abstract: A method of cleaving off a daughter single crystal substrate from a parent single crystal substrate includes providing a stress-mandrel and the parent a single crystal substrate. The parent single crystal substrate has a major surface and an edge surface that intersects the major surface. The major surface extends along a major surface plane. The stress-mandrel has a stress-mandrel coefficient of thermal expansion that is higher than the parent single crystal coefficient of thermal expansion. The method includes bonding the stress-mandrel to the major surface, and cooling the parent single crystal substrate and the stress-mandrel. The cooling of the parent single crystal substrate bonded to the stress-mandrel provides a thermal stress in the parent single crystal substrate sufficient to cleave the parent single crystal substrate. The cleaving extends substantially along a plane parallel to the plane of the major surface. In one embodiment the cleaved daughter substrate was used to make a photovoltaic cell.

Abstract: A conductive layer in an integrated circuit is formed as a sandwich having multiple sublayers, including at least two sublayers of oriented carbon nanotubes. A first sublayer is created by growing carbon nanotubes in a first direction parallel to the chip substrate from a catalyst in the presence of a reactant gas flow in the first direction, and a second sublayer is created by growing carbon nanotubes in a second direction parallel to the substrate and different from the first direction from a catalyst in the presence of a reactant gas flow in the second direction. The first and second directions are preferably substantially perpendicular. The conductive layer sandwich preferably contains one or more additional sublayers of a conductive material, such as a metal.

Abstract: An immersion lithography apparatus and method, and a lithographic optical column structure are disclosed for conducting immersion lithography with at least the projection optics of the optical system and the wafer in different fluids at the same pressure. In particular, an immersion lithography apparatus is provided in which a supercritical fluid is introduced about the wafer, and another fluid, e.g., an inert gas, is introduced to at least the projection optics of the optical system at the same pressure to alleviate the need for a special lens. In addition, the invention includes an immersion lithography apparatus including a chamber filled with a supercritical immersion fluid and enclosing a wafer to be exposed and at least a projection optic component of the optical system.

Abstract: Methods for synthesizing carbon nanotubes and structures formed thereby, includes forming carbon nanotubes on a plurality of synthesis sites supported by a first substrate, interrupting nanotube synthesis, mounting a free end of each carbon nanotube to a second substrate, and removing the first substrate. Each carbon nanotube is capped by one of the synthesis sites, to which growth reactants have ready access.

Abstract: Carbon nanotube field effect transistors, arrays of carbon nanotube field effect transistors, device structures, and arrays of device structures. A stacked device structure includes a gate electrode layer and catalyst pads each coupled electrically with a source/drain contact. The gate electrode layer is divided into multiple gate electrodes and at least one semiconducting carbon nanotube is synthesized by a chemical vapor deposition process on each of the catalyst pads. The gate electrode has a sidewall covered by a gate dielectric and at least one semiconducting carbon nanotube adjacent to the sidewall of the gate electrode. Source/drain contacts are electrically coupled with opposite ends of the semiconducting carbon nanotube to complete the device structure. Multiple device structures may be configured either as a memory circuit or as a logic circuit.

Abstract: A conductive layer in an integrated circuit is formed as a sandwich having multiple sublayers, including at least one sublayer of oriented carbon nanotubes. The conductive layer sandwich preferably contains two sublayers of carbon nanotubes, in which the carbon nanotube orientation in one sublayer is substantially perpendicular to that of the other layer. The conductive layer sandwich preferably contains one or more additional sublayers of a conductive material, such as a metal. In one embodiment, oriented carbon nanotubes are created by forming a series of elongated parallel catalyst strips on a horizontal surface, and growing carbon nanotubes from the catalyst in the presence of a directional flow of reactant gases.

Abstract: A method for forming carbon nanotube field effect transistors, arrays of carbon nanotube field effect transistors, and device structures and arrays of device structures formed by the methods. The methods include forming a stacked structure including a gate electrode layer and catalyst pads each coupled electrically with a source/drain contact. The gate electrode layer is divided into multiple gate electrodes and at least one semiconducting carbon nanotube is synthesized by a chemical vapor deposition process on each of the catalyst pads. The completed device structure includes a gate electrode with a sidewall covered by a gate dielectric and at least one semiconducting carbon nanotube adjacent to the sidewall of the gate electrode. Source/drain contacts are electrically coupled with opposite ends of the semiconducting carbon nanotube to complete the device structure. Multiple device structures may be configured either as a memory circuit or as a logic circuit.

Abstract: A conductive layer in an integrated circuit is formed as a sandwich having multiple sublayers, including at least one sublayer of oriented carbon nanotubes. The conductive layer sandwich preferably contains two sublayers of carbon nanotubes, in which the carbon nanotube orientation in one sublayer is substantially perpendicular to that of the other layer. The conductive layer sandwich preferably contains one or more additional sublayers of a conductive material, such as a metal. In one embodiment, oriented carbon nanotubes are created by forming a series of parallel surface ridges, covering the top and one side of the ridges with a catalyst inhibitor, and growing carbon nanotubes horizontally from the uncovered vertical sides of the ridges. In another embodiment, oriented carbon nanotubes are grown on the surface of a conductive material in the presence of a directional flow of reactant gases and a catalyst.

Abstract: Vertical device structures incorporating at least one nanotube and methods for fabricating such device structures by chemical vapor deposition. Each nanotube is grown by chemical vapor deposition catalyzed by a catalyst pad and encased in a coating of a dielectric material. Vertical field effect transistors may be fashioned by forming a gate electrode about the encased nanotubes such that the encased nanotubes extend vertically through the thickness of the gate electrode. Capacitors may be fashioned in which the encased nanotubes and the corresponding catalyst pad bearing the encased nanotubes forms one capacitor plate.

Abstract: A memory gain cell for a memory circuit, a memory circuit formed from multiple memory gain cells, and methods of fabricating such memory gain cells and memory circuits. The memory gain cell includes a storage device capable of holding a stored electrical charge, a write device, and a read device. The read device includes a fin of semiconducting material, electrically-isolated first and second gate electrodes flanking the fin, and a source and drain formed in the fin adjacent to the first and the second gate electrodes. The first gate electrode is electrically coupled with the storage device. The first and second gate electrodes are operative for gating a region of the fin defined between the source and the drain to thereby regulate a current flowing from the source to the drain. When gated, the magnitude of the current is dependent upon the electrical charge stored by the storage device.

Abstract: A method of patterning which provides images substantially smaller than that possible by lithographic techniques is provided. In the method of the invention, a substrate has a memory layer and a sacrificial layer formed thereon. An image is patterned onto the memory layer by protecting an edge during an etching step using chemical oxide removal (COR) processes, for example. Another edge is memorized in the layer. The sacrificial layer is removed to expose another memorized edge, which is used to define a pattern in an underlying layer.

Abstract: A memory gain cell for a memory circuit, a memory circuit formed from multiple memory gain cells, and methods of fabricating such memory gain cells and memory circuits. The memory gain cell includes a storage device capable of holding a stored electrical charge, a write device, and a read device. The read device includes a fin of semiconducting material, electrically-isolated first and second gate electrodes flanking the fin, and a source and drain formed in the fin adjacent to the first and the second gate electrodes. The first gate electrode is electrically coupled with the storage device. The first and second gate electrodes are operative for gating a region of the fin defined between the source and the drain to thereby regulate a current flowing from the source to the drain. When gated, the magnitude of the current is dependent upon the electrical charge stored by the storage device.

Abstract: A field effect transistor is formed having wrap-around, vertically-aligned, dual gate electrodes. Starting with a silicon-on-insulator (SOI) structure having a buried silicon island, a vertical reference edge is defined, by creating a cavity within the SOI structure, and used during two etch-back steps that can be reliably performed. The first etch-back removes a portion of an oxide layer for a first distance over which a gate conductor material is then applied. The second etch-back removes a portion of the gate conductor material for a second distance. The difference between the first and second distances defines the gate length of the eventual device. After stripping away the oxide layers, a vertical gate electrode is revealed that surrounds the buried silicon island on all four side surfaces.

Abstract: A hybrid semiconductor structure which includes a horizontal semiconductor device and a vertical carbon nanotube transistor, where the vertical carbon nanotube transistor and the horizontal semiconductor device have at least one shared node is provided. The at least one shared node can include, for example, a drain, source or gate electrode of a FET, or an emitter, collector, or base of a bipolar transistor.

Abstract: To isolate two active regions formed on a silicon-on-insulator (SOI) substrate, a shallow trench isolation region is filled with liquid phase deposited silicon dioxide (LPD-SiO2) while avoiding covering the active areas with the oxide. By selectively depositing the oxide in this manner, the polishing needed to planarize the wafer is significantly reduced as compared to a chemical-vapor deposited oxide layer that covers the entire wafer surface. Additionally, the LPD-SiO2 does not include the growth seams that CVD silicon dioxide does. Accordingly, the etch rate of the LPD-SiO2 is uniform across its entire expanse thereby preventing cavities and other etching irregularities present in prior art shallow trench isolation regions in which the etch rate of growth seams exceeds that of the other oxide areas.

Abstract: Conductive paths in an integrated circuit are formed using multiple undifferentiated carbon nanotubes embedded in a conductive metal, which is preferably copper. Preferably, conductive paths include vias running between conductive layers. Preferably, composite vias are formed by forming a metal catalyst pad on a conductor at the via site, depositing and etching a dielectric layer to form a cavity, growing substantially parallel carbon nanotubes on the catalyst in the cavity, and filling the remaining voids in the cavity with copper. The next conductive layer is then formed over the via hole.

Abstract: A memory gain cell for a memory circuit, a memory circuit formed from multiple memory gain cells, and methods of fabricating such memory gain cells and memory circuits. The memory gain cell includes a storage device capable of holding a stored electrical charge, a write device, and a read device. The read device includes a fin of semiconducting material, electrically-isolated first and second gate electrodes flanking the fin, and a source and drain formed in the fin adjacent to the first and the second gate electrodes. The first gate electrode is electrically coupled with the storage device. The first and second gate electrodes are operative for gating a region of the fin defined between the source and the drain to thereby regulate a current flowing from the source to the drain. When gated, the magnitude of the current is dependent upon the electrical charge stored by the storage device.

Abstract: A conductive layer in an integrated circuit is formed as a sandwich having multiple sublayers, including at least one sublayer of oriented carbon nanotubes. The conductive layer sandwich preferably contains two sublayers of carbon nanotubes, in which the carbon nanotube orientation in one sublayer is substantially perpendicular to that of the other layer. The conductive layer sandwich preferably contains one or more additional sublayers of a conductive material, such as a metal. In one embodiment, oriented carbon nanotubes are created by forming a series of parallel surface ridges, covering the top and one side of the ridges with a catalyst inhibitor, and growing carbon nanotubes horizontally from the uncovered vertical sides of the ridges. In another embodiment, oriented carbon nanotubes are grown on the surface of a conductive material in the presence of a directional flow of reactant gases and a catalyst.