Abstract: A method is provided for fabricating molecular electronic devices comprising at least a bottom electrode and a molecular switch film on the bottom electrode. The method includes forming the bottom electrode by a process including: cleaning portions of the substrate where the bottom electrode is to be deposited; pre-sputtering the portions; depositing a conductive layer on at least the portions; and cleaning the top surface of the conductive layer. Advantageously, the conductive electrode properties include: low or controlled oxide formation (or possibly passivated), high melting point, high bulk modulus, and low diffusion. Smooth deposited film surfaces are compatible with Langmuir-Blodgett molecular film deposition. Tailored surfaces are further useful for SAM deposition. The metallic nature gives high conductivity connection to molecules. Barrier layers may be added to the device stack, i.e., Al2O3 over the conductive layer.

Abstract: A method is provided for fabricating molecular electronic devices comprising at least a bottom electrode and a molecular switch film on the bottom electrode. The method includes forming the bottom electrode by a process including: cleaning portions of the substrate where the bottom electrode is to be deposited; pre-sputtering the portions; depositing a conductive layer on at least the portions; and cleaning the top surface of the conductive layer. Advantageously, the conductive electrode properties include: low or controlled oxide formation (or possibly passivated), high melting point, high bulk modulus, and low diffusion. Smooth deposited film surfaces are compatible with Langmuir-Blodgett molecular film deposition. Tailored surfaces are further useful for SAM deposition. The metallic nature gives high conductivity connection to molecules. Barrier layers may be added to the device stack, i.e., Al2O3 over the conductive layer.

Abstract: A method is provided for fabricating molecular electronic devices comprising at least a bottom electrode and a molecular switch film on the bottom electrode. The method includes forming the bottom electrode by a process including: cleaning portions of the substrate where the bottom electrode is to be deposited; pre-sputtering the portions; depositing a conductive layer on at least the portions; and cleaning the top surface of the conductive layer. Advantageously, the conductive electrode properties include: low or controlled oxide formation (or possibly passivated), high melting point, high bulk modulus, and low diffusion. Smooth deposited film surfaces are compatible with Langmuir-Blodgett molecular film deposition. Tailored surfaces are further useful for SAM deposition. The metallic nature gives high conductivity connection to molecules. Barrier layers may be added to the device stack, i.e., Al2O3 over the conductive layer.

Abstract: A method is provided for fabricating molecular electronic devices comprising at least a bottom electrode and a molecular switch film on the bottom electrode. The method includes forming the bottom electrode by a process including: cleaning portions of the substrate where the bottom electrode is to be deposited; pre-sputtering the portions; depositing a conductive layer on at least the portions; and cleaning the top surface of the conductive layer. Advantageously, the conductive electrode properties include: low or controlled oxide formation (or possibly passivated), high melting point, high bulk modulus, and low diffusion. Smooth deposited film surfaces are compatible with Langmuir-Blodgett molecular film deposition. Tailored surfaces are further useful for SAM deposition. The metallic nature gives high conductivity connection to molecules. Barrier layers may be added to the device stack, i.e., Al2O3 over the conductive layer.

Abstract: Methods for making electronic devices where a molecular monolayer or multilayer is sandwiched between top and bottom electrodes at electrode intersections. The molecular layer has an electrical characteristic such as bistable switching. A layer of electrically conductive material is used to protect the molecular layer during formation of the top electrode pattern. The electrically conductive material remains sandwiched between the top and bottom electrodes at the electrode intersections in the final electronic device.

Abstract: Methods for making electronic devices where a molecular monolayer or multilayer is sandwiched between top and bottom electrodes at electrode intersections. The molecular layer has an electrical characteristic such as bistable switching. A layer of electrically conductive material is used to protect the molecular layer during formation of the top electrode pattern. The electrically conductive material remains sandwiched between the top and bottom electrodes at the electrode intersections in the final electronic device.

Abstract: Bistable molecules are provided with at least one photosensitive functional group. As thus constituted, the bistable molecules are photopatternable, thereby allowing fabrication of micrometer-scale and nanometer-scale circuits in discrete areas without relying on a top conductor as a mask. The bistable molecules may comprise molecules that undergo redox reactions, such as rotaxanes and catenanes, or may comprise molecules that undergo an electric-field-induced band gap change that causes the molecules, or a portion thereof, to rotate, bend, twist, or otherwise change from a substantially fully conjugated state to a less conjugated state. The change in states in the latter case results in a change in electrical conductivity.

Abstract: A device for precision alignment of a write element of a tape head to a transport direction of a media that is transported across the tape head is disclosed. The tape head includes at least one alignment element that is cofabricated with the write element so that both the write element and the alignment element have a fixed orientation with respect to a magnetic axis of the tape head. The alignment element and the write element can be fabricated on the tape head using standard microelectronic photolithographic processes. Preferably, the tape head includes a plurality of alignment elements. Those alignment elements are operative to write alignment transitions onto the media. The alignment transitions can be observed to determine if they are indicative of the write element having a predetermined orientation with respect to the transport direction.

Abstract: A device for precision alignment of a write element of a tape head to a transport direction of a media that is transported across the tape head is disclosed. The tape head includes at least one alignment element that is cofabricated with the write element so that both the write element and the alignment element have a fixed orientation with respect to a magnetic axis of the tape head. The alignment element and the write element can be fabricated on the tape head using standard microelectronic photolithographic processes. Preferably, the tape head includes a plurality of alignment elements. Those alignment elements are operative to write alignment transitions onto the media. The alignment transitions can be observed to determine if they are indicative of the write element having a predetermined orientation with respect to the transport direction.

Abstract: A batch fabrication technique is described that increases the manufacturing efficiency of servo write heads and also improves servo pattern definition for fine features, while reducing tape and head wear. Multiple heads are fabricated as a batch from one or more ferrite wafers. A nominally flat, large wafer surface and a contour suitable for uniform photoresist application an planar photolithography permit fine servo pattern definition with low linewidth variation. Non-magnetic material is photolithographically defined to produce gaps above a spacer. The non-magnetic material may be photoresist, semiconductor materials, glass, metal or the like. The material may even be removed later to leave air gaps. Additionally, a lower ferrite wafer may be mated to the upper ferrite wafer to complete a magnetic circuit around the gaps. A rounded leading edge on the head creates an air bearing to reduce ware of the tape and of the head.

Abstract: Bistable molecules are provided with at least one photosensitive functional group. As thus constituted, the bistable molecules are photopatternable, thereby allowing fabrication of micrometer-scale and nanometer-scale circuits in discrete areas without relying on a top conductor as a mask. The bistable molecules may comprise molecules that undergo redox reactions, such as rotaxanes and catenanes, or may comprise molecules that undergo an electric-field-induced band gap change that causes the molecules, or a portion thereof, to rotate, bend, twist, or otherwise change from a substantially fully conjugated state to a less conjugated state. The change in states in the latter case results in a change in electrical conductivity.

Abstract: A cross point memory array is fabricated on a substrate with a plurality of memory cells, each memory cell including a diode and an anti-fuse in series. First and second conducting materials are disposed in separate strips on the substrate to form a plurality of first and second orthogonal electrodes with cross points. A plurality of semiconductor layers are disposed between the first and second electrodes to form a plurality of diodes between the cross points of the first and second electrodes. A passivation layer is disposed between the first electrodes and the diodes to form a plurality of anti-fuses adjacent to the diodes at the cross points of first and second electrodes. Portions of the diode layers are removed between the electrode cross points to form the plurality of memory cells with rows of trenches between adjacent memory cells to provide a barrier against crosstalk between adjacent memory cells. The trenches extend substantially to the depth of the n-doped layer in each diode.

Abstract: A technique is provided for forming a molecule or an array of molecules having a defined orientation relative to the substrate or for forming a mold for deposition of a material therein. The array of molecules is formed by dispersing them in an array of small, aligned holes (nanopores), or mold, in a substrate. Typically, the material in which the nanopores are formed is insulating. The underlying substrate may be either conducting or insulating. For electronic device applications, the substrate is, in general, electrically conducting and may be exposed at the bottom of the pores so that one end of the molecule in the nanopore makes electrical contact to the substrate. A substrate such as a single-crystal silicon wafer is especially convenient because many of the process steps to form the molecular array can use techniques well developed for semiconductor device and integrated-circuit fabrication.

Abstract: Methods for making electronic devices where a molecular monolayer or multilayer is sandwiched between top and bottom electrodes at electrode intersections. The molecular layer has an electrical characteristic such as bistable switching. A layer of electrically conductive material is used to protect the molecular layer during formation of the top electrode pattern. The electrically conductive material remains sandwiched between the top and bottom electrodes at the electrode intersections in the final electronic device.

Abstract: A batch fabrication technique is described that increases the manufacturing efficiency of servo write heads and also improves servo pattern definition for fine features, while reducing tape and head wear. Multiple heads are fabricated as a batch from one or more ferrite wafers. A nominally flat, large wafer surface and a contour suitable for uniform photoresist application and planar photolithography permit fine servo pattern definition. A rounded leading edge on the head creates an air bearing to reduce wear of the tape and of the head. Moreover, any head wear occurs at the leading edge rather than in the region of the head where the servo pattern is formed. The servo write head may have a substantially planar head surface. A leading edge is disposed adjacent to the head surface such that the tape contacts the leading edge before passing over the head surface. The leading edge is rounded to form an air bearing between the head surface and the tape.

Abstract: A cross point memory array is fabricated on a substrate with a plurality of memory cells, each memory cell including a diode and an anti-fuse in series. First and second conducting materials are disposed in separate strips on the substrate to form a plurality of first and second orthogonal electrodes with cross points. A plurality of semiconductor layers are disposed between the first and second electrodes to form a plurality of diodes between the cross points of the first and second electrodes. A passivation layer is disposed between the first electrodes and the diodes to form a plurality of anti-fuses adjacent to the diodes at the cross points of first and second electrodes. Portions of the diode layers are removed between the electrode cross points to form the plurality of memory cells with rows of trenches between adjacent memory cells to provide a barrier against crosstalk between adjacent memory cells. The trenches extend substantially to the depth of the n-doped layer in each diode.

Abstract: An electronic switching device is provided that comprises a pair of electrodes and an organic molecular film disposed between the pair of electrodes. The organic molecular film comprises molecules that undergo molecular-mechanical motion between at least two different energetic states. The molecular-mechanical motion comprises any combination of stretching, bending, or torsion of selected bonds, including breaking or making bonds (other than covalent bonds) at specific locations. Changing the electronic properties of the molecule permits its use as a switch, storage element, or logic device.

Abstract: An improved method of fabricating nanometer-scale devices is provided, wherein the improvement comprises: (1) employing materials for a first electrode, a first insulating layer, if present, a molecular switch layer, a second insulating layer, if present, and a second electrode that permit photopatterning of the second electrode; and (2) photopatterning at least the second electrode without adversely affecting the molecular switch layer. The improved method incorporates known techniques on a smaller scale than previously done to provide a means to move away from shadow mask electrodes (many micrometers wide), presently used in nanometer-scale devices, and move to nanometer dimensions. The improved method further facilitates integration of nanometer-scale devices to larger silicon-based technology.

Abstract: A batch fabrication technique is described that increases the manufacturing efficiency of servo write heads and also improves servo pattern definition for fine features, while reducing tape and head wear. Multiple heads are fabricated as a batch from one or more ferrite wafers. A nominally flat, large wafer surface and a contour suitable for uniform photoresist application and planar photolithography permit fine servo pattern definition. A rounded leading edge on the head creates an air bearing to reduce wear of the tape and of the head. Moreover, any head wear occurs at the leading edge rather than in the region of the head where the servo pattern is formed. The servo write head may have a substantially planar head surface. A leading edge is disposed adjacent to the head surface such that the tape contacts the leading edge before passing over the head surface. The leading edge is rounded to form an air bearing between the head surface and the tape.

Abstract: A head design that reduces wear at the leading and trailing edges where the tape contacts the head while minimizing any adverse effects on the performance of the head. In one embodiment of the invention, a localized layer of wear resistant material is formed on the leading edge where the tape contacts the head before passing over the head recording surface. In a second embodiment, the leading edge is formed as wear resistant material embedded in the head structure adjacent to the recording surface. And, in a third embodiment, the leading edge is formed as a wear resistant material strip affixed to the side of the head structure. For each embodiment, the wear resistant material may also be applied in the manner described to the trailing edge where the tape may also contact the head after passing over the recording surface.