Al/AlOx/Al Josephson Junctions Fabricated by Shadow Evaporation Employing Multiple Symmetric Angled Depositions Per Channel

A modification to the Manhattan shadow method for metal deposition was studied in the fabrication of Josephson Junctions (JJs). To highlight the need for the modified Manhattan shadow method, fabrication without and with the modification was performed and analyzed. Without the modification to the shadow method, disconnects in the JJ top electrode caused by shadowing from the bottom electrode were observed. Employing an additional Al deposition (at 180
$^{\circ }$
rotation) in the initial shadow deposition produced functional JJs with enhanced uniformity of top electrode coverage. Analysis comparing the deposition method without and with the modification is provided through scanning electron microscopy (SEM), atomic force microscopy (AFM), and JJ IV characterizations at temperatures as low as 10 mK.