Open AccessCharacteristics of an infrared sensor formed with a few molecular layers of vinylidene fluoride oligomers with in situ poling during vacuum evaporation
Author(s) -
Yohei Sutani,
Tatsuya Fukushima,
Yasuko Koshiba,
Shohei Horike,
Tetsuhiro Kodani,
Takashi Kubo,
Kenji Ishida
Publication year - 2019
Publication title -
japanese journal of applied physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 129
eISSN - 1347-4065
pISSN - 0021-4922
DOI - 10.7567/1347-4065/ab5502
Subject(s) - poling , pyroelectricity , materials science , vacuum evaporation , electric field , infrared , electrode , evaporation , optoelectronics , polarization (electrochemistry) , layer (electronics) , analytical chemistry (journal) , thin film , ferroelectricity , optics , composite material , dielectric , chemistry , nanotechnology , physics , quantum mechanics , thermodynamics , chromatography
Perpendicularly oriented vinylidene fluoride oligomer thin films with six molecular layers were poled during vacuum evaporation (in situ poling) using a micro-gapped comb-like electrode, and their pyroelectric characteristics were investigated. The extent of polarization achieved with in situ poling performed by applying a low electric field (7.7 MV m −1 ) is the same as that achieved by conventional post-poling with the application of a high electric field (>100 MV m −1 ). Despite using a film with a few molecular layers, the in situ poled sensor showed pyroelectric response without the use of an infrared ray absorption layer; voltage sensitivity of 198 V W −1 was obtained, which is much higher than that of the post-poled sensor (∼16 V W −1 ). The improvement in sensitivity is attributed to the amount of charge injected during the poling treatment.