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Updated: Jun 19, 2026
08:43
Effect of Bending on the Electrical Characteristics of Flexible Organic Single Crystal-based Field-effect Transistors
Published on: November 7, 2016
Threshold voltage and space charge in organic transistors.
I Gutiérrez Lezama1, A F Morpurgo
1DPMC and GAP, Université de Genéve, CH1211 Geneva, Switzerland.
Physical Review Letters
|October 2, 2009
Summary
We studied rubrene single-crystal field-effect transistors to understand threshold voltage shifts. Our findings show space charge transfer from contacts can be quantitatively modeled, revealing insights into charge carrier effective mass.
Area of Science:
- Organic electronics
- Semiconductor physics
- Materials science
Background:
- Rubrene single crystals are promising organic semiconductors.
- Understanding charge transport mechanisms is crucial for device performance.
- Field-effect transistors (FETs) are key tools for semiconductor characterization.
Purpose of the Study:
- To systematically investigate the threshold voltage shift in rubrene single-crystal FETs.
- To quantitatively model the observed voltage shifts using fundamental physical principles.
- To demonstrate the utility of FET measurements for determining microscopic semiconductor parameters.
Main Methods:
- Fabrication and characterization of stable and reproducible rubrene single-crystal FETs.
- Systematic measurement of threshold voltage shifts as a function of channel length and source-drain voltage.
- Quantitative modeling using Poisson's equation and semiconductor density of states assumptions.
Main Results:
- Threshold voltage shifts in rubrene FETs are reproducible and systematically measurable.
- The observed shifts are quantitatively explained by space charge transfer from contacts.
- The modeling approach requires no free fitting parameters, validating assumptions about rubrene's electronic structure.
- Demonstrated consistency with previous experimental findings on rubrene crystals.
Conclusions:
- Space charge transfer from contacts is a dominant factor influencing threshold voltage in rubrene FETs.
- Rubrene's electronic properties, when studied via FETs, align with conventional inorganic semiconductor models.
- FET measurements provide a powerful, quantitative method for determining essential microscopic parameters like charge carrier effective mass in organic semiconductors.
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