am9b22165_si_001.pdf (1006.54 kB)
Structure–Property Relation in Organic–Metal Oxide Hybrid Phototransistors
journal contribution
posted on 2020-03-17, 13:33 authored by Zetian Chen, Gil Sheleg, Himanshu Shekhar, Nir TesslerWe report an optoelectronic
device consisting of a solution-processed indium gallium zinc oxide
(IGZO) thin-film transistor and vacuum-deposited small organic molecules.
Depending on the configurations of the organic materials, either bulk
heterojunction or planar heterojunction (PHJ), the device assumes
the functionality of either a photosensor or a photoinduced memory,
respectively. Under λ = 625 nm light illumination, the photosensor
shows response and recovery time of ∼50 ms, responsivity of
∼5 mA/W, sensitivity above 104, and a linear response.
The mechanism of the photoinduced memory is studied experimentally
and verified using a device simulation. We find that the memory is
due to long charge retention time at the organic PHJ interface which
is stable for over 9 days. It is correlated with the low leakage current
found in ordered organic junctions having low subgap tail states.
The presented integration of the PHJ with the transistor constitutes
a new design of write-once-read-many-times memory device that is likely
to be attractive for low-cost applications.