TY - JOUR
T1 - Electrical and optical characterization of extended SWIR detectors based on thin films of nano-columnar PbSe
AU - Manis-Levy, Hadar
AU - Tempelman, Tzvi
AU - Maman, Nitzan
AU - Shikler, Rafi
AU - Visoly-Fisher, Iris
AU - Golan, Yuval
AU - Sarusi, Gabby
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - There is an increasing demand for detectors with extended Short Wavelength Infrared (SWIR) absorption at wavelengths between 1.6 μm and 2.8 μm. Towards that end, PbSe absorber layers were grown by the Chemical-Bath-Deposition (CBD) technique in a nano-columnar morphology on n-type (1 0 0) oriented GaAs substrate, where the nano-columns are densely packed perpendicular to the substrate. The spectral absorption edge and photoluminescence (PL) peak of these layers were blue shifted from the bulk bandgap of 4.7 μm to 2.2 μm, i.e., within the extended SWIR range, due to quantum confinement effect. Current voltage (I-V) measurements were carried out in a vertical geometry of different circular mesa sizes (250–2000 μm in diameter). The area dependent current–voltage measurements indicate a densely packed layer with no apparent pinholes. On the other hand, it was found out that surface leakage currents on the mesa perimeters are the dominant mechanism of the dark current. A photo-response to SWIR illumination was evident, confirming the feasibility of using such structures as extended SWIR photodetectors upon minimizing leakage currents using surface treatments.
AB - There is an increasing demand for detectors with extended Short Wavelength Infrared (SWIR) absorption at wavelengths between 1.6 μm and 2.8 μm. Towards that end, PbSe absorber layers were grown by the Chemical-Bath-Deposition (CBD) technique in a nano-columnar morphology on n-type (1 0 0) oriented GaAs substrate, where the nano-columns are densely packed perpendicular to the substrate. The spectral absorption edge and photoluminescence (PL) peak of these layers were blue shifted from the bulk bandgap of 4.7 μm to 2.2 μm, i.e., within the extended SWIR range, due to quantum confinement effect. Current voltage (I-V) measurements were carried out in a vertical geometry of different circular mesa sizes (250–2000 μm in diameter). The area dependent current–voltage measurements indicate a densely packed layer with no apparent pinholes. On the other hand, it was found out that surface leakage currents on the mesa perimeters are the dominant mechanism of the dark current. A photo-response to SWIR illumination was evident, confirming the feasibility of using such structures as extended SWIR photodetectors upon minimizing leakage currents using surface treatments.
UR - http://www.scopus.com/inward/record.url?scp=85057126093&partnerID=8YFLogxK
U2 - 10.1016/j.infrared.2018.09.029
DO - 10.1016/j.infrared.2018.09.029
M3 - Article
AN - SCOPUS:85057126093
SN - 1350-4495
VL - 96
SP - 89
EP - 97
JO - Infrared Physics and Technology
JF - Infrared Physics and Technology
ER -