Fabrication of deep-sub-micrometer NbN/AlN/NbN epitaxial junctions on a Si-substrate
Fabrication of deep-sub-micrometer NbN/AlN/NbN epitaxial junctions on a Si-substrate
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DOI：
10.35848/1882-0786/abbfde
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发表时间：
2020-12-01
影响因子：
2.3
通讯作者：
Terai, Hirotaka
中科院分区：
文献类型：
--
作者：
Qiu, Wei;Terai, Hirotaka
我们开发了一种在氮化钛（TiN）缓冲硅（Si）衬底上制备超小型、全外延氮化铌（NbN）约瑟夫森结的新工艺。我们使用电子束光刻来定义结，随后进行反应离子刻蚀（RIE）。化学机械抛光工艺以及使用三氟甲烷（CHF3）气体的反应离子刻蚀为结电极形成了可靠的电接触。所有结，其结尺寸直径小至0.27微米，都显示出优异的电流 - 电压特性，具有明显的能隙和较小的亚能隙泄漏电流。我们已经证实，在去除二氧化硅（SiO2）介电中间层之后，结的质量得以保持。
We have developed a novel fabrication process for ultra-small, full-epitaxial NbN Josephson junctions on a TiN buffered silicon (Si) substrate. We use an electron beam lithography for junction definition followed by a reactive-ion-etch (RIE). A chemical mechanical polishing process and an RIE by using CHF3 gas formed reliable electrical contacts for the junction electrodes. All junctions, with a junction size down to 0.27 mu m in diameter, showed excellent current-voltage characteristics with a clear gap and small sub-gap leakage current. We have confirmed that the quality of the junctions was maintained after the removal of the SiO2 dielectric interlayer.