Josephson Junction Oxidation Process
Original Publication Date: 1985-Aug-01
Included in the Prior Art Database: 2005-Feb-19
Spatially uniform, isotropic oxidation of Josephson junctions may be carried out, at higher partial pressures than normally applied, by pretreating the oxygen in a glow discharge in an auxiliary chamber prior to the oxygen entry into the process chamber, which does not contain a plasma discharge. In the figure, process chamber 1 holds sample 2 to be oxidized. Auxiliary chamber 3 receives O2 gas, which passes through glow discharge 4 and is thus partially ionized to relatively reactive O+ and O2+ ions which then pass in the O2 flow to process chamber l. Standard plasma oxidation processes for Josephson junctions expose the samples directly to the plasma. Because of the spatial inhomogeneity of the plasma, various systematic spatial variations are generated in the Josephson critical current density J1 .