NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Scalable, High-Speed, Digital Single-Flux-Quantum Circuits at NIST
Published
Author(s)
Pete Hopkins, Manuel Castellanos Beltran, Christine A. Donnelly, Paul Dresselhaus, David Olaya, Adam Sirois, Samuel P. Benz
Abstract
We describe NIST's capabilities for designing and fabricating niobium-based single-flux quantum (SFQ) digital and mixed-signal circuits and show test results of our first circuits. We have assembled a package of software design tools that are readily available and sufficient for designing, simulating, and optimizing circuits. A scalable process including four niobium metal layers and partial planarization of the insulating layers has been developed based on intrinsically shunted Josephson junctions with tunable niobium-doped amorphous-silicon barriers. This process can be extended to demonstrate dense, high-speed SFQ circuits. Through our participation in IARPA's Cryogenic Computing Complexity (C3) program, we have built liquid- helium cryogenic probes and test systems with 40 and 80 input/outputs for characterizing advanced SFQ circuits at speeds up to 26 GHz.
Proceedings Title
International Superconductive Electronics Conference
Hopkins, P.
, Castellanos Beltran, M.
, Donnelly, C.
, Dresselhaus, P.
, Olaya, D.
, Sirois, A.
and Benz, S.
(2017),
Scalable, High-Speed, Digital Single-Flux-Quantum Circuits at NIST, International Superconductive Electronics Conference, Sorrento, IT, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923301
(Accessed October 1, 2025)