Fabrication of Single-crystal Superconducting Tunnel Junctions, and Photodevice Applications

我们用分子束外延技术制备了外延生长的Al薄膜作为超导材料。用反射高能电子衍射仪(RHEED)、原子力显微镜(AFM)和剩余电阻比(RRR)对薄膜进行了表征。研究了Al在Al_2O_3(0001)和Si(111)衬底上的生长，在100℃左右的衬底温度下获得了相对较高的RRR为15的平坦表面。我们还尝试了外延生长的氧化镁薄膜作为绝缘体材料的沉积和STJ的制作。在Al/MgO/Al结顶表面成功观察到条纹状RHEED图案。外延生长的结在0.3K温度下表现出良好的SIS特性。

We fabricated epitaxial-grown Al film as superconductor materials by molecular beam epitaxy. These films were characterized by reflection high-energy electron diffraction (RHEED), atomic force microscope (AFM) and residual resistance ratio (RRR) measurement. The growth of Al was investigated on Al2O3 (0001) and Si (111) substrates, and flat surface with relatively high RRR of 15 was realized at substrate temperatures around 100 degrees Celsius. We also tried the deposition of epitaxial-grown MgO film as an insulator material and STJ fabrication. A streak RHEED pattern was successfully observed at the top surface of Al/MgO/Al junctions. The epitaxial-grown junctions showed good SIS characteristics in 0.3 K measurements.