The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 11, 1984
Filed:
Nov. 29, 1982
Theodore A Fulton, Warren Township, Somerset County, NJ (US);
Shin-Shem Pei, New Providence, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A method for changing Josephson device parameters, e.g., the critical current of a Josephson junction. The method comprises incorporating doping material into the device, or part of the device, followed by a light anneal. Exemplary dopants include In, Sn, Sb, Te, Bi, Hg, Mg, Li, Cd, Na and Ta, with In, Sn, and Sb being preferred dopants for changing the critical current of a Josephson junction having a Pb-containing counter electrode. The dopant can be incorporated into the device by in-diffusion after deposition onto the surface, by ion implantation, or by any other convenient method. The amount of dopant required is typically small. For example, deposition of a Sn layer of 0.05 nm effective thickness onto the 200 nm thick Pb-Sb(1.5 wt. %) counter electrode of a cross-type Josephson junction, and annealing at 80.degree. C. for about 3 hours, resulted in an increase in the critical current of the junction by a factor of about 2.5. The method is considered to have wide applicability in the manufacture of Josephson devices, and can be applied globally, i.e., to all the devices on a wafer or chip, or locally, i.e., to selected devices.