date: november 18, 2020
oleksandr grynko with co-authors: tristen thibault, emma pineau, gytis juska and alla
reznik, published the paper “bilayer lead oxide x-ray photoconductor for lag-free operation” in
the scientific reports – nature. congratulations oleksandr on this published paper.
abstract
polycrystalline lead oxide (poly-pbo) was considered one of the most promising
photoconductors for the direct conversion x-ray medical imaging detectors due to its previous
success in optical imaging, i.e., as an optical target in so-called plumbicon video pick-up tubes.
however, a signal lag which accompanies x-ray excitation, makes poly-pbo inapplicable as an
x-ray-to-charge transducer in real-time x-ray imaging. in contrast, the recently synthesized
amorphous lead oxide (a-pbo) photoconductor is essentially lag-free. here, we report on our
approach to a pbo detector where a thin layer of a-pbo is combined with a thick layer of poly-
pbo for lag-free operation. in the presented a-pbo/poly-pbo bilayer structure, the poly-pbo
layer serves as an x-ray-to-charge transducer while the a-pbo acts as a lag prevention layer. the
hole mobility in the a-pbo/poly-pbo bilayer structure was measured by photo-charge extraction
by linearly increasing voltage technique at different temperatures and electric fields to
investigate charge transport properties. it was found that the hole mobility is similar to that in a-
se—currently the only commercially viable photoconductor for the direct conversion x-ray
detectors. evaluation of the x-ray temporal performance demonstrated complete suppression of
signal lag, allowing operation of the a-pbo/poly-pbo detector in real-time imaging.
continue reading the article: https://doi.org/10.1038/s41598-020-77050-w
