Circuits made from nanotube-based switching elements with multiple controls

Abstract

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 depending on the construction.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Pat. Apl., Ser. No. 60 / 494,889, filed on Aug. 13, 2003, entitled Nanoelectromechanical Nanotube-Based Logic, which is incorporated herein by reference in its entirety. This application also claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Pat. Apl., Ser. No. 60 / 561330, filed on Apr. 12, 2004, entitled Non-volatile CNT Dual-Rail Differential Logic, which is incorporated herein by reference in its entirety. [0002] This application is related to the following references: [0003] U.S. Pat. Apl., Ser. No. not yet assigned, filed on date even herewith, entitled Nanotube-Based Switching Elements; [Nan-31][0004] U.S. Pat. Apl., Ser. No. not yet assigned, filed on date even herewith, entitled Nanotube-Based Switching Elements And Logic Circuits; [Nan-78][0005] U.S. Pat. Apl., Ser. No. not yet assigned, filed on date even herewith, entitled Isolation Structur...

AI Technical Summary

Benefits of technology

[0025] Under another aspect of the invention, the at least one nanotube switching elements is capable of non-volatilely retaining informational state includes a nanotube channel element having at least one electrically conductive nanotube and a control structure disposed in relation to the nanotube channel element to controllably form and unform an electrically conductive channel between an input node of the at least one switching element and an output node of the at least one switching element.

[0026] Under another aspect of the invention, a latch circuit includes at least one input terminal and an output terminal, and a first and a second inverter circuit. Each inverter circuit includes a nanotube switching element having an input node, an output node, a nanotube channel ele

Problems solved by technology

However, the density of bipolar digital integrated circuits is limited by their high power consumption and the ability of packaging technology to dissipate the heat produced while the circuits are operating.

The density and operating speed of MOS digital circuits are still limited by the need to dissipate the heat produced when the device is operating.

Digital logic integrated circuits constructed from bipolar or MOS devices do not function correctly under conditions of high heat or extreme environments.

As leakage current increases, the operating temperature of the device rises, the power consumed by the circuit increases, and the difficulty of discriminating the off state from the on state reduces circuit reliability.

Conventional digital logic circuits also short internally when subjected to certain extreme environments because electrical currents are generated inside the semiconductor material.

It is possible to manufacture integrated circuits with special devices and isolation techniques so that they remain operational when exposed to such environments, but the high cost of these devices limits their availability and practicality.

In addition, such digital circuits exhibit timing differences from their normal counterparts, requiring additional design verification to add protection to an existing design.

Integrated circuits constructed from either bipolar or FET switching elements are volatile.

Alternative solutions to avoid losing information in volatile digital circuits, such as battery backup, also add cost and complexity to digital designs.

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