Abstract
Nb/AlO x /Nb superconducting tunnel junctions with low leakage current were fabricated. The ultra low leakage current was maintained after 100 thermal cycles. X-rays were detected with three sizes of junctions on several wafers. The pulse height spectra show the improvement of energy resolution with the increase in junction area. Using the diffusion length of excited electrons in the superconductor, the effect of dispersion of excited electron from the junction area to the electric lead and trap of excited electrons at the film edge (energy diffusion effect) was evaluated. Calculated results explain the characteristics of the experimental results. It is concluded that a large junction area is desirable to reduce the energy diffusion effect on the energy resolution.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
