Abstract：Low temperature superconducting devices based on Nb/Al-AlOx/Nb Josephson junctions are widely used, one of the keys to fabricate high-quality S-I-S Josephson junctions is to deposit high-quality Nb/Al-AlOx/Nb trilayer. Many property parameters can influence the quality of trilayer, such as the residual resistance ratio(R.R.R),superconducting transition temperature (Tc),surface roughness,film stress, the thickness of aluminum(Al) film and so on. By analyzing the relationships of the parameters above with different sputtering conditions, the best deposition condition can be determined. Also, different critical current densities of Nb/Al-AlOx/Nb trilayer can be obtained by controlling the oxidation pressure and time of Al.
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2023, Vol. 44 
