摘要:
Resistive elements include a patterned region of nanofabric having a predetermined area, where the nanofabric has a selected sheet resistance; and first and second electrical contacts contacting the patterned region of nanofabric and in spaced relation to each other. The resistance of the element between the first and second electrical contacts is determined by the selected sheet resistance of the nanofabric, the area of nanofabric, and the spaced relation of the first and second electrical contacts. The bulk resistance is tunable.
摘要:
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.
摘要:
A hybrid memory system having electromechanical memory cells is discussed. A memory cell core circuit has an array of electromechanical memory cells, in which each cell is a crossbar junction at least one element of which is a nanotube or a nanotube ribbon. An access circuit provides array addresses to the memory cell core circuit to select at least one corresponding cell. The access circuit is constructed of semiconductor circuit elements.
摘要:
Sensor platforms and methods of making them are described. A platform having a non-horizontally oriented sensor element comprising one or more nanostructures such as nanotubes is described. Under certain embodiments, a sensor element has or is made to have an affinity for an analyte. Under certain embodiments, such a sensor element comprises one or more pristine nanotubes. Under certain embodiments, the sensor element comprises derivatized or functionalized nanotubes. Under certain embodiments, a sensor is made by providing a support structure; providing one or more nanotubes on the structure to provide material for a sensor element; and providing circuitry to electrically sense the sensor element's electrical characterization. Under certain embodiments, the sensor element comprises pre-derivatized or pre-functionalized nanotubes. Under other embodiments, sensor material is derivatized or functionalized after provision on the structure or after patterning. Under certain embodiments, a large-scale array of sensor platforms includes a plurality of sensor elements.
摘要:
Nanotube-based switching elements with multiple controls and circuits made from such. A switching element includes an input node, an output node, and a nanotube channel element having at least one electrically conductive nanotube. A control structure is disposed in relation to the nanotube channel element to controllably form and unform an electrically conductive channel between said input node and said output node. The output node is constructed and arranged so that channel formation is substantially unaffected by the electrical state of the output node. The control structure includes a control electrode and a release electrode, disposed on opposite sides of the nanotube channel element. The control and release may be used to form a differential input, or if the device is constructed appropriately to operate the circuit in a non-volatile manner. The switching elements may be arranged into logic circuits and latches having differential inputs and/or non-volatile behavior.
摘要:
Nanotube device structures and methods of fabrication. A method of making a nanotube switching element includes forming a first structure having at a first output electrode; forming second structure having a second output electrode; forming a conductive article having at least one nanotube, the article having first and second ends; positioning the conductive article between said first and second structures such that the first structure clamps the first and second ends of the article to the second structure, and such that the first and second output electrodes are opposite each other with the article positioned therebetween; providing at least one signal electrode in electrical communication with the conductive article; and providing at least one control electrode in spaced relation to the conductive article such that the control electrode may control the conductive article to form a conductive pathway between the signal electrode and the first output electrode.
摘要:
Field effect devices having a gate controlled via a nanotube switching element. Under one embodiment, a non-volatile transistor device includes a source region and a drain region of a first semiconductor type of material and each in electrical communication with a respective terminal. A channel region of a second semiconductor type of material is disposed between the source and drain region. A gate structure is disposed over an insulator over the channel region and has a corresponding terminal. A nanotube switching element is responsive to a first control terminal and a second control terminal and is electrically positioned in series between the gate structure and the terminal corresponding to the gate structure. The nanotube switching element is electromechanically operable to one of an open and closed state to thereby open or close an electrical communication path between the gate structure and its corresponding terminal. When the nanotube switching element is in the closed state, the channel conductivity and operation of the device is responsive to electrical stimulus at the terminals corresponding to the source and drain regions and the gate structure.
摘要:
Random access memory including nanotube switching elements. A memory cell includes first and second nanotube switching elements and an electronic memory. Each nanotube switching element includes conductive terminals, a nanotube article and control circuitry capable of controllably form and unform an electrically conductive channel between the conductive terminals. The electronic memory is a volatile storage device capable of storing a logic state in response to electrical stimulus. In certain embodiment the electronic memory has cross-coupled first and second inverters in electrical communication with the first and second nanotube switching elements. The cell can operate as a normal electronic memory, or can operate in a shadow memory or store mode (e.g., when power is interrupted) to transfer the electronic memory state to the nanotube switching elements. The device may later be operated in a recall mode where the state of the nanotube switching elements may be transferred to the electronic memory.
摘要:
A method of forming an aligned connection between a nanotube layer and an etched feature is disclosed. An etched feature is formed having a top and a side and optionally a notched feature at the top. A patterned nanotube layer is formed such that the nanotube layer contacts portions of the side and overlaps a portion of the top of the etched feature. The nanotube layer is then covered with an insulating layer. Then a top portion of the insulating layer is removed to expose a top portion of the etched feature.
摘要:
A nanotube-based switching element includes an input node, an output node, and a nanotube channel element having at least one electrically conductive nanotube. A control structure is disposed in relation to the nanotube channel element to controllably form and unform an electrically conductive channel between said input node and said output node. The output node is constructed and arranged so that channel formation is substantially unaffected by the electrical state of the output node. The control structure includes a control electrode and a release electrode, disposed on opposite sides of the nanotube channel element. The control and release may be used to form a differential input, or if the device is constructed appropriately to operate the circuit in a non-volatile manner. The switching elements may be arranged into logic circuits and latches having differential inputs and/or non-volatile behavior.