Planarized Fabrication Process With Two Layers of SIS Josephson Junctions and Integration of SIS and SFS π-Junctions
Planarized Fabrication Process With Two Layers of SIS Josephson Junctions and Integration of SIS and SFS π-Junctions
复制标题
具有两层 SIS 约瑟夫森结的平面化制造工艺以及 SIS 和 SFS π 结的集成
DOI:
10.1109/tasc.2019.2901709
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发表时间:
2019
影响因子:
1.8
通讯作者:
L. Johnson
中科院分区:
文献类型:
--
作者:
S. K. Tolpygo;V. Bolkhovsky;R. Rastogi;S. Zarr;A. Day;E. Golden;T. Weir;A. Wynn;L. Johnson
We present our new fabrication process for superconductor electronics that integrates two layers of Josephson junctions (JJs) in a fully planarized multilayer process on 200-mm wafers. The two junction layers can be, e.g., conventional superconductor-insulator-superconductor (SIS) Nb/Al/AlO<sub>x</sub>/Nb junctions with the same or different Josephson critical current densities, <italic>J</italic><sub>c</sub>. The process also allows integration of high-<italic>J</italic><sub>c</sub> superconductor–ferromagnet–superconductor (SFS) or SFS'S JJs on the first junction layer with Nb/Al/AlO<sub>x</sub>/Nb trilayer junctions on the second JJ layer, or vice versa. In the present node, the SFS trilayer, Nb/Ni/Nb is placed below the standard SIS trilayer and separated by one niobium wiring layer. The main purpose of integrating the SFS and SIS junction layers is to provide compact π-phase shifters in logic cells of superconductor digital circuits and random access memories, and thereby increase the integration scale and functional density of superconductor electronics. The current node of the two-junction-layer process has six planarized niobium layers, two layers of resistors, and 350-nm minimum feature size. The target critical current densities for the SIS JJs are 100 <italic>μ</italic>A/<italic>μ</italic>m<sup>2</sup> and 200 <italic>μ</italic>A/<italic>μ</italic>m<sup>2</sup>. We present the salient features of the new process, fabrication details, and characterization results on two layers of JJs integrated into one process, both for the conventional and π-junctions.
DOI:
--
发表时间:
2020
期刊:
影响因子:
--
作者:
Taro Yamashita;Kun Zuo;Yoshiro Urade;Wei Qiu;Hirotaka Terai;Akira Fujimaki and Yasunobu Nakamura
通讯作者:
Akira Fujimaki and Yasunobu Nakamura
影响因子:
3.6
作者:
Yamanashi Yuki;Nakaishi Sotaro;Sugiyama Akira;Takeuchi Naoki;Yoshikawa Nobuyuki
通讯作者:
Yoshikawa Nobuyuki
DOI:
--
发表时间:
2005
期刊:
IEEE TRANSACTIONS ON Applied Superconductivity 15
影响因子:
--
作者:
Shin'ichi Morohashi;Shin'ichi Morohashi;Shin'ichi Morohashi;Shin'ichi Morohashi;Shin'ichi Morohashi;Shin'ichi Morohashi
通讯作者:
Shin'ichi Morohashi