Molecular-Beam Epitaxial Growth of a Far-Infrared Transparent Electrode for Extrinsic Germanium Photoconductors

作者：Suzuki Toyoaki^*; Wada Takehiko; Hirose Kazuyuki; Makitsubo Hironobu; Kaneda Hidehiro

来源：Publications of the Astronomical Society of the Pacific, 2012, 124(918): 823-829.

DOI：10.1086/667391

We have evaluated the optical and electrical properties of a far-infrared (IR) transparent electrode for extrinsic germanium (Ge) photoconductors at 4 K, which was fabricated by molecular beam epitaxy (MBE). As a far-IR transparent electrode, an aluminum (Al)-doped Ge layer is formed at well-optimized doping concentration and layer thickness in terms of the three requirements: high far-IR transmittance, low-resistivity, and excellent ohmic contact. The Al-doped Ge layer has the far-IR transmittance of %26gt;95% within the wavelength range of 40-200 mu m, while low-resistivity (similar to 5 Omega cm) and ohmic contact are ensured at 4 K. We demonstrate the applicability of the MBE technology in fabricating the far-IR transparent electrode satisfying the above requirements.

• 出版日期2012-8