||NIST fabricated the first 10-volt chip made of all-niobium superconducting electrodes, which made it less susceptible to damage from handling and contamination. The chip is 10 millimeters by 20 millimeters in size and has 20,208 junctions made of niobium electrodes with aluminum-oxide barriers. The circuit design and fabrication process was transferred to industry and became the basis for the first commercial superconducting quantum voltage standard.
*PML, volt, chip, circuit
See also http://www.nist.gov/pml/history-volt/superconductivity_1990s.cfm.