Peng, Y.H.Y.H.PengChen, C.C.C.C.ChenCHIEH-HSIUNG KUANCheng, H.H.H.H.Cheng2018-09-102018-09-10200300381101http://www.scopus.com/inward/record.url?eid=2-s2.0-0041592438&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/303179https://www.scopus.com/inward/record.uri?eid=2-s2.0-0041592438&doi=10.1016%2fS0038-1101%2803%2900136-9&partnerID=40&md5=96b42fc094123849ce2facff6a2015daA p-type Ge quantum dot infrared photodetector is investigated in this paper. The intrinsic thick Si layers are utilized to block the dark current under low bias and adjust the tunneling probability by controlling applied field to tune the responsivity spectrum. The 30 K responsivity spectrum shows broadband from 2 to 9 μm at zero bias with photovoltaic effect and extends its range to 20 μm when the applied bias is increased. For long wavelength detection, our detector is tunable with Si blocking layer. The detectivity in this sample has maximum value toward 2.1 × 1010 cm (Hz0.5)/W under 0.2 V for the 6 μm wavelength. That for the long wavelength is ∼109 cm (Hz0.5)/W. © 2003 Elsevier Ltd. All rights reserved.Blocking layer; Ge quantum dot infrared photodetector; Long wavelength infrared photodetector; Wavelength tunability[SDGs]SDG7Electric currents; Infrared radiation; Photodetectors; Photovoltaic effects; Semiconducting silicon; Spectrum analysis; Blocking layers; Semiconductor quantum dotsconference paper10.1016/S0038-1101(03)00136-92-s2.0-0041592438