Fabrication of Nb / AIN , / NbTiN Junctions for SIS Mixer Applications
Fabrication of Nb / AIN , / NbTiN Junctions for SIS Mixer Applications
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用于 SIS 混合器应用的 Nb / AIN 、 / NbTiN 结的制造
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
K. Megerian
中科院分区：
文献类型：
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作者：
H. Leduc;J. Stern;K. Megerian
我们讨论了超导体-绝缘体-超导体（SIS）结，通常表现出3.5 mV的总间隙电压的制造和特性。对于低至RNA = 8 C2 pm2的抗性区域产物，接头具有I & c/RN = 27的子缺口与正常状态抗性比率，并且已经用低至4 R pm2的RNA产物产生了高质量的接头。该器件结构包括Nb基极、通过薄Al邻近层的等离子体氮化形成的隧道势垒和NbTiN反电极。结果为所有铌结与高电流密度氮化铝障碍也显示。铝层的氮化是通过控制在真空处理室中的单独的射频驱动电极上的直流浮动电位来研究的。器件被集成到一个混频器天线结构，该结构将NbTiN作为接地平面。线路层可以是普通金属或NbTiN。退火结果显示I-V特性改善，RNA产物增加。最近的接收机测量采用这些结表现出低噪声性能高达900 GHz。lizdex Terms-AIN，铌，NbTiN，超导器件，SIS混频器，太赫兹探测器。
We discuss fabrication and characteristics of superconductor-insulator-superconductor (SIS) junctions which typically exhibit a 3.5 mV sum-gap voltage. Junctions have a sub-gap to normal state resistance ratio of I&c / RN = 27 for resistance area products down to RNA = 8 C2 pm2 and high quality junctions have been produced with RNA products as low as 4 R pm2 . The device structure incorporates a Nb base electrode, a tunnel barrier formed by plasma nitridation of a thin AI proximity layer, and a NbTiN counter-electrode. Results for all Nb junctions with high current density aluminumnitride barriers are also shown. Nitridation of the aluminum layer is investigated by control of the dc floating potential on a separate rf driven electrode in the vacuum process chamber. Devices are integrated to a mixer antenna structure incorporating NbTiN as a ground plane. The wire circuit layer can be either normal metal or NbTiN. Annealing results show improved I-V characteristics with increased RNA products. Recent receiver measurements employing these junctions exhibit low noise performance up to 900 GHz. lizdex Terms-AIN, Niobium, NbTiN, Superconductor device, SIS Mixers, THz detector.