TY  - JOUR
A1  - Koopman, Wouter-Willem Adriaan
A1  - Muccini, Michele
A1  - Toffanin, Stefano
T1  - High-resolution photoluminescence electro-modulation microscopy by scanning lock-in
JF  - Review of scientific instruments : a monthly journal devoted to scientific instruments, apparatus, and techniques
N2  - Morphological inhomogeneities and structural defects in organic semiconductors crucially determine the charge accumulation and lateral transport in organic thin-film transistors. Photoluminescence Electro-Modulation (PLEM) microscopy is a laser-scanning microscopy technique that relies on the modulation of the thin-film fluorescence in the presence of charge-carriers to image the spatial distribution of charges within the active organic semiconductor. Here, we present a lock-in scheme based on a scanning beam approach for increasing the PLEM microscopy resolution and contrast. The charge density in the device is modulated by a sinusoidal electrical signal, phase-locked to the scanning beam of the excitation laser. The lock-in detection scheme is achieved by acquiring a series of images with different phases between the beam scan and the electrical modulation. Application of high resolution PLEM to an organic transistor in accumulation mode demonstrates its potential to image local variations in the charge accumulation. A diffraction-limited precision of sub-300 nm and a signal to noise ratio of 21.4 dB could be achieved. Published by AIP Publishing.
Y1  - 2018
U6  - https://doi.org/10.1063/1.5010281
SN  - 0034-6748
SN  - 1089-7623
VL  - 89
IS  - 4
PB  - American Institute of Physics
CY  - Melville
ER  -