Doping effect of Organic Semicondcutors

Electrical Doping of Organic Semiconductors

What is the Electrical Doping?

In organic semiconductor, Electrical doping is the process of intentionally introducing impurities into an intrinsic organic semiconductor for the purpose of modulating its electrical properties.

Doping of organic semiconductors is an important technique for reducing the driving voltage and improving the power efficiency of organic electronic devices. Since doped organic semiconductor layers in organic light emitting diodes (OLEDs) or organic photovoltaic cells (OPVs) reduce the contact resistance between electrodes and organic materials, p-doped/intrinsic/n-doped (p-i-n) structures have been used to realize highly efficient OLEDs and OPVs.


Doping effect of Organic Semicondcutors


(a) The J-V characteristics of hole only devices fabricated using doped 2TNATA films with 25 mol% ReO3, MoO3 and CuI, and undoped 2TNATA film. (b) Carrier density vs. doping concentration for ReO3, MoO3 and CuI doped2TNATA films.


Nanoclusters of Transition Metal Oxide dopants


Bright-field TEM image of (a) undoped NPB, (b) ReO3- and (c) MoO3-doped NPB (25 mol%). (d) and (e): diffractionpatterns of (a) and (b), respectively. (f): High-resolution TEM image of (b). The NPB film doped with MO shows dark spots in the image coming from the MO nanoclusters.


Impedance analysis of Doped Organic Semiconductors


Real (filled) and imaginary parts (empty) of impedance spectra as functions of frequency of hole only device before and after annealing process.