(color online) (a)–(d) Film evaporation in the junction area (the cross section marked with the blue dashed line in Fig. 1). (e)–(h) Film evaporations at the lead area (the cross section marked with the red dashed line in Fig. 1). The oxidation process between two evaporations is not shown. (a), (e) Before evaporation. The sizes of the groove are L and l, respectively. (b), (f) Evaporations of the junction bottom layer with an angle θ with respect to the substrate plane. (c), (g) Evaporation of the top aluminum layer after rotating the sample holder 90 degrees with an angle θ with respect to the substrate plane. (d), (h) Final view of our junction and lead.