Academia Sinica
Research Brochure
ASIAA Login
Research Gallery > Atacama Large Millimeter/submillimeter Array (ALMA)
Research Gallery
Atacama Large Millimeter/submillimeter Array (ALMA)
| Epitaxial ultrathin NbN superconducting films for Terahertz application |
|
Image Credit: Chang, Hsiao-Wen
We have realized the epitaxial growth of ultrathin δ-NbN films on 3C-SiC/HRSi substrates. Even with a thickness of 1.3 nm (~3 unit-cells), the δ-NbN film shows a superconducting transition above 8 K. The critical current of 2.7 nm film is 0.59 mA, corresponding to critical current density of 2.2 MA/cm2.
|
| Superconducting δ-NbN ultrathin film becomes a key element on extremely sensitive detector applications in recent decades because of its excellent electronic properties. We have realized the epitaxial growth of ultrathin δ-NbN films on (100)-oriented 3C-SiC/Si substrates by dc reactive magnetron sputtering at 760 oC with a deposition rate of 0.054 nm/sec. High-resolution transmission electron microscope images confirm the excellent epitaxy of these films. Even with a thickness of 1.3 nm (~3 unit-cells), the δ-NbN film shows a superconducting transition above 8 K. Furthermore, our ultrathin δ-NbN films demonstrate a long Ginzburg-Landau superconducting coherent length (>5 nm) with critical current density about 2.2 MA/cm2, and good stability in ambient environment. |
asiaa.sinica.edu.tw