Abstract: Under one aspect, a covered nanotube switch includes: (a) a nanotube element including an unaligned plurality of nanotubes, the nanotube element having a top surface, a bottom surface, and side surfaces; (b) first and second terminals in contact with the nanotube element, wherein the first terminal is disposed on and substantially covers the entire top surface of the nanotube element, and wherein the second terminal contacts at least a portion of the bottom surface of the nanotube element; and (c) control circuitry capable of applying electrical stimulus to the first and second terminals. The nanotube element can switch between a plurality of electronic states in response to a corresponding plurality of electrical stimuli applied by the control circuitry to the first and second terminals. For each different electronic state, the nanotube element provides an electrical pathway of different resistance between the first and second terminals.

Abstract: Under one aspect, a memory array includes word lines; bit lines; memory cells; and a memory operation circuit. Each memory cell responds to electrical stimulus on a word line and on a bit line and includes: a two-terminal non-volatile nanotube switching device having first and second terminals, a semiconductor diode element, and a nanotube fabric article capable of multiple resistance states. The semiconductor diode and nanotube article are between and in electrical communication with the first and second terminals, which are coupled to the word line bit line respectively. The operation circuit selects cells by activating bit and/or word lines, detects a resistance state of the nanotube fabric article of a selected memory cell, and adjusts electrical stimulus applied to the cell to controllably induce a selected resistance state in the nanotube fabric article. The selected resistance state corresponds to an informational state of the memory cell.

Abstract: Under one aspect, a non-volatile nanotube switch includes a first terminal; a nanotube block including a multilayer nanotube fabric, at least a portion of which is positioned over and in contact with at least a portion of the first terminal; a second terminal, at least a portion of which is positioned over and in contact with at least a portion of the nanotube block, wherein the nanotube block is constructed and arranged to prevent direct physical and electrical contact between the first and second terminals; and control circuitry capable of applying electrical stimulus to the first and second terminals. The nanotube block can switch between a plurality of electronic states in response to a plurality of electrical stimuli applied by the control circuitry to the first and second terminals. For each different electronic state, the nanotube block provides an electrical pathway of different resistance between the first and second terminals.

Abstract: Under one aspect, a nonvolatile nanotube diode includes: a substrate; a semiconductor element disposed over the substrate, the semiconductor element having an anode and a cathode and capable of forming an electrically conductive pathway between the anode and the cathode; a nanotube switching element disposed over the semiconductor element, the nanotube switching element including a conductive contact and a nanotube fabric element capable of a plurality of resistance states; and a conductive terminal disposed in spaced relation to the conductive contact, wherein the nanotube fabric element is interposed between and in electrical communication with the conductive contact and the conductive contact is in electrical communication with the cathode, and wherein in response to electrical stimuli applied to the anode and the conductive terminal, the nonvolatile nanotube diode is capable of forming an electrically conductive pathway between the anode and the conductive terminal.

Abstract: Under one aspect, a method of making a nanotube switch includes: providing a substrate having a first conductive terminal; depositing a multilayer nanotube fabric over the first conductive terminal; and depositing a second conductive terminal over the multilayer nanotube fabric, the nanotube fabric having a thickness, density, and composition selected to prevent direct physical and electrical contact between the first and second conductive terminals. In some embodiments, the first and second conductive terminals and the multilayer nanotube fabric are lithographically patterned so as to each have substantially the same lateral dimensions, e.g., to each have a substantially circular or rectangular lateral shape. In some embodiments, the multilayer nanotube fabric has a thickness from 10 nm to 200 nm, e.g., 10 nm to 50 nm. The structure may include an addressable diode provided under the first conductive terminal or deposited over the second terminal.

Abstract: Under one aspect, a non-volatile nanotube diode device includes first and second terminals; a semiconductor element including a cathode and an anode, and capable of forming a conductive pathway between the cathode and anode in response to electrical stimulus applied to the first conductive terminal; and a nanotube switching element including a nanotube fabric article in electrical communication with the semiconductive element, the nanotube fabric article disposed between and capable of forming a conductive pathway between the semiconductor element and the second terminal, wherein electrical stimuli on the first and second terminals causes a plurality of logic states.

Abstract: Under one aspect, a nanotube diode includes: a cathode formed of a semiconductor material; and an anode formed of nanotubes. The cathode and anode are in fixed and direct physical contact, and are constructed and arranged such that sufficient electrical stimulus applied to the cathode and the anode creates a conductive pathway between the cathode and the anode. In some embodiments, the anode includes a non-woven nanotube fabric having a plurality of unaligned nanotubes. The non-woven nanotube fabric may have a thickness, e.g., of 0.5 to 20 nm. Or, the non-woven nanotube fabric may include a block of nanotubes. The nanotubes may include metallic nanotubes and semiconducting nanotubes, and the cathode may include an n-type semiconductor material. A Schottky barrier can form between the n-type semiconductor material and the metallic nanotubes and/or a PN junction can form between the n-type semiconductor material and the semiconducting nanotubes.

Abstract: A non-volatile memory cell includes a volatile storage device that stores a corresponding logic state in response to electrical stimulus; and a shadow memory device coupled to the volatile storage device. The shadow memory device receives and stores the corresponding logic state in response to electrical stimulus. The shadow memory device includes a non-volatile nanotube switch that stores the corresponding state of the shadow device.

Abstract: Under one aspect, a covered nanotube switch includes: (a) a nanotube element including an unaligned plurality of nanotubes, the nanotube element having a top surface, a bottom surface, and side surfaces; (b) first and second terminals in contact with the nanotube element, wherein the first terminal is disposed on and substantially covers the entire top surface of the nanotube element, and wherein the second terminal contacts at least a portion of the bottom surface of the nanotube element; and (c) control circuitry capable of applying electrical stimulus to the first and second terminals. The nanotube element can switch between a plurality of electronic states in response to a corresponding plurality of electrical stimuli applied by the control circuitry to the first and second terminals. For each different electronic state, the nanotube element provides an electrical pathway of different resistance between the first and second terminals.

Abstract: A doubly clamped beam has an asymmetric piezoelectric layer within the beam with a gate proximate to the beam within a submicron distance with a gate and beam dipole. A suspended beam is formed using a Cl2/He plasma etch supplied at a flow rate ratio of 1:9 respectively into a plasma chamber. A parametric amplifier comprises a NEMS signal beam driven at resonance and a pair of pump beams driven at twice resonance to generate a modulated Lorentz force on the pump beams to perturb the spring constant of the signal beam. A bridge circuit provides two out-of-phase components of an excitation signal to a first and second NEMS beam in a first and second arm. A DC current is supplied to an AC driven NEMS device to tune the resonant frequency.