1. NRI Analog Nanoelectronics (Involving Carbon Nanotube and Graphene Nanoribbons) and Printed Electronic Analog Circuits: Single Nanotube/Nanoribbon Implementations of Analog Current Sources, Differential Amplifiers, Operational Amplifiers, Comparators, and Associated Design Techniques
Many nanoscale electrical sensors, actuators, and transducers operate in an electrically linear fashion, while almost all multi-transistor nanoscale circuits developed and explored in the literature are digital. Further, most multi-transistor nanoscale circuits employ a single nanotube for each transistor, an unscalable situation that is difficult to fabricate. NRI’s work shows how to make differential amplifiers, and from these operation amplifier circuits, all on a single carbon/graphene nanotube or nanoribbon, by using a novel “chain-leapfrog” circuit design technique. It is shown that standard differential amplifier and operation amplifier circuit configurations are naturally implementable with this technique. Part of the “chain-leapfrog” technique involves fully-nanoscale single (FET) nano-transistor constant-current sources at power-supply nodes, which allows for “sewing” alternating positive and negative power supply rails across a single carbon/graphene nanotube or nanoribbon and consecutively interconnected transistors (“chaining) with other interconnection paths among metalized pads (“leap-frogging”). Accordingly, a single carbon/graphene nanotube or nanoribbon can be draped over a metalized pad contact array to make operational amplifiers, comparators, and even A/D and D/A converters. The same technique can be used with printed semiconductor electronics on a far larger physical scale. CAD-based design tools and circuit library systems can be developed that automate and institutionalize contact-array configurations and the “chain-leapfrog” circuit topology technique. Optoelectronic properties of carbon/graphene nanotubes and nanoribbons were also included in this work.
NRI’s original work with different amplifiers was done in 2007 and included explicit designs for fully-nanoscale single (FET) nano-transistor constant-current sources. Several years later Army ARL Technical Report ARL-TR-5151 “Differential Amplifier Circuits Based on Carbon Nanotube Field Effect Transistors (CNTFETs)” by M. Chin and S. Kilpatrick was published (April 2010). This Army ARL work did not employ an active constant-current source, instead using a resistor which limits performance (as stated in the report, and a known property of any two-transistor differential amplifier).
NRI’s early patent work in the area of nanoelectronic differential amplifiers and related circuits implemented on a segment of a graphene nanoribbon was cited in the survey book “Fullerenes—Advances in Research and Application: 2013 Edition” (ISBN 1490100199, 9781490100197) pp.707-708.
NRI’s work in this area was sold in 2011.
2. More NRI Recent Work
NRI’s current R&D in Molecular Electronics is directed two other entirely new original approaches to molecular electronics and molecular devices. One of NRI’s new molecular electronics approaches is working to combine direct molecular electronics signal interfacing with chemical, magnetic, spintronic, photonic, and other quantum processes and phenomena.
Pending Published Applications
|Towards the Very Smallest Electronic Circuits and Systems: Transduction, Signal Processing, and Digital Logic in Molecular Fused-Rings via Mesh Ring-Currents
Pending Unpublished Applications
|Towards the Very Smallest Electronic Molecular Electronic Circuits and Systems: Heterogeneous-Input, Transduction, Signal Processing, and Digital Logic in Molecular Fused-Rings via Ring Currents