Open AccessPolarization Raman Imaging of Organic Monolayer Islands for Crystal Orientation Analysis
Author(s) -
Toki Moriyama,
Takayuki Umakoshi,
Yoshiaki Hattori,
Koki Taguchi,
Prabhat Verma,
M. Kitamura
Publication year - 2021
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.0c06313
Subject(s) - monolayer , raman spectroscopy , polarization (electrochemistry) , materials science , organic semiconductor , crystal (programming language) , optics , chemistry , optoelectronics , nanotechnology , physics , computer science , programming language
An organic semiconductor film made of diphenyl derivative dinaphtho[2,3- b :2',3'- f ]thieno[3,2- b ]thiophene (DPh-DNTT) has high carrier mobility. However, this mobility may be greatly affected by the crystal orientation of the DPh-DNTT's first layer. Polarization Raman microscopy is widely used to quantitatively analyze the molecular orientation, and thus holds great potential as a powerful tool to investigate the crystal orientation of monolayer DPh-DNTT with high spatial resolution. In this study, we demonstrate polarization Raman imaging of monolayer DPh-DNTT islands for crystal orientation analysis. We found that the DPh-DNTT sample indicated a strong dependence of the Raman intensity on the incident polarization direction. Based on the polarization dependence, we developed an analytical method of determining the crystal orientation of the monolayer DPh-DNTT islands and experimentally confirmed that our technique was highly effective at imaging the islands' crystal orientation with a spatial resolution of a few hundred nanometers.