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arXiv · 1206.5368

Molecular-beam epitaxial growth of a far-infrared transparent electrode for extrinsic Germanium photoconductors

Toyoaki Suzuki·Takehiko Wada·Kazuyuki Hirose·Hironobu Makitsubo·Hidehiro Kaneda
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Abstract

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 >95 % within the wavelength range of 40--200 microns, while low resistivity (~5 ohm-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.

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Toyoaki Suzuki, Takehiko Wada, Kazuyuki Hirose, Hironobu Makitsubo, Hidehiro Kaneda. 2012-06-23. Molecular-beam epitaxial growth of a far-infrared transparent electrode for extrinsic Germanium photoconductors. https://doi.org/10.1086/667391

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