Development of STJ for neutron detector on Si-LBO hybrid substrate by surface-activated room-temperature bonding

29th International Symposium on Superconductivity

Endo, S.^1,2 ; Fujii, G.^2 ; Ukibe, M.^2 ; Takagi, H.^2 ; Ohkubo, M.^2 ; Naruse, M.^1 ; Myoren, H.^1 ; Otani, C.^3 ; Taino, T.^1

Graduate School of Science and Engineering Saitama University, 225 Shimo-Ohkubo, Sakura-ku, Saitama

338-8570, Japan^1

AIST, 1-1-1 Umezono, Tsukuba-shi, Ibaraki

305-8568, Japan^2

RIKEN, 519-1399 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi

980-0845, Japan^3

关键词: Active area;    Ar ion beams;    Bonding methods;    High spatial resolution;    Hybrid substrates;    Li2B4O7;    Room temperature bonding;    Superconducting tunnel junction;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/871/1/012070/pdf
DOI  :  10.1088/1742-6596/871/1/012070

来源: IOP

【 摘 要 】

We have been developing superconducting tunnel junctions (STJs) for neutron detector on a Si-Li2B4O7(LBO) hybrid substrate. An active area of each STJ was limited by dicing in order to obtain high spatial resolution. The Si-LBO hybrid substrate was bonded by a surface-activated room-temperature bonding. In this bonding method, the Si and LBO surfaces were sputter-etched by high energy Ar ion beam and bonded in a vacuum. We fabricated STJs on the Si-LBO hybrid substrate and measured their current-voltage characteristic. Their leakage currents (Ileak) were