Search results for "Photoresponse"
showing 3 items of 3 documents
Qualitative Models for the Photoresponse and Capacitance of Annealed Titania Nanotubes
2015
Physicochemical characterization of annealed TiO2 nanotubes (TNTs) was conducted by using photocurrent spectroscopy and differential capacitance techniques. It has been shown that the geometry and architecture of nanotubes determine how photogenerated electrons and holes are separated and transferred. Photocurrent generation in TNTs is a consequence of two phenomena; drifting of holes into the electrolyte and diffusion of electrons toward the substrate. These two processes have been shown to be independent of the anodic polarization. The capacitance of TiO2 nanotubes is also affected by their geometry. In anodic potentials, with respect to the flat band potential of the underlying barrier l…
Transient photoresponse and incident power dependence of high-efficiency germanium quantum dot photodetectors
2012
We report a systematic study of time-resolved and power-dependent photoresponse in high-efficiency germanium quantum dot photodetectors (Ge-QD PDs), with internal quantum efficiencies greater than 100 over a broad wavelength, reverse bias, and incident power range. Turn-on and turn-off response times (τ on and τ off) are shown to depend on series resistance, bias, optical power, and thickness (W QD) of the Ge-QD layer, with measured τ off values down to ∼40 ns. Two different photoconduction regimes are observed at low and high reverse bias, with a transition around -3 V. A transient current overshoot phenomenon is also observed, which depends on bias and illumination power. © 2012 American …
Inkjet Printable ZnO/PEDOT:PSS Heterojunction for Thin Flexible Semi-Transparent Optoelectronic Sensors
2020
International audience; Flexible sensors play an increasing role in printed electronics and are of interest for optoelectronic applications in flexible robotics and industrial automation. Thus, we have investigated the hybrid inorganic-organic junction between ZnO and PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate). A thin ITO (indium tin oxide) layer on PET (polyethylene terephthalate) foils was used as substrate electrode. ZnO was deposited from a nanoparticle (NP) suspension by electrophoretic deposition. For comparison, we have used three different methods for the deposition of PEDOT:PSS, namely (i) drop casting, (ii) dip-coating, (iii) inkjet printing. For the result…