Detecting Defects in Organic Semiconductors
Nanoscale images of IR reflectivity enable investigation of defects due to molecular orientation in thin organic films . IR-neaSCOPE + s is equipped with neaspec patented s-SNOM technology , which simultaneously measures reflectivity and absorption of organic compounds , proving an invaluable tool for advancing organic semiconductor materials and devices .
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4.2 |
1.4 |
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nanoscale surface reflectivity , revealed by |
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A NF
( a . u .)
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3.0
2.0
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0.8 |
Φ NF
( rad )
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IR s-SNOM amplitude ANF , proved to be invaluable for determining the molecular orientation of islands inside a diindenoperylene ( DIP ,
C 32
H 16
) organic semiconductor film , which has a
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0.7 |
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0.3 profound impact on the device performance . This is because light-induced anisotropic response of vibrational modes strongly affects the s-SNOM amplitude , while not causing significant changes in material absorption ( s-SNOM phase or AFM- IR ). High-resolution images measured at 1450 cm −1 reveal distinct regions in the s-SNOM amplitude signal : red areas where molecules lie down and blue areas where they stand up relative to the sample . Thus , IR-neaSCOPE + s stands out as a unique tool for molecular defect analysis , which is essential for the advancement of devices based
2 µ m |
on organic molecular semiconductors . |
Overlay of s-SNOM reflectivity ( 1450 cm -1 ) on AFM topography
IR nanoscopy reveals molecular orientation in organic semiconductors .
N . Mrkyvkova et al ., The Journal of Physical Chemistry C 2021 , 125 ( 17 ), 9229-9235