Parameter-free continuous drift-diffusion models of amorphous organic semiconductors.

Area of Science:

• Organic electronics
• Materials science
• Semiconductor device physics

Background:

• Continuous drift-diffusion models are standard for optimizing organic semiconducting devices.
• Material properties in these models depend on temperature, charge density, and external fields, often using Gaussian disorder models.
• Existing analytic expressions and lattice models have limitations in their applicability and approximations.

Purpose of the Study:

• To overcome limitations of current drift-diffusion models in organic electronics.
• To propose and validate a novel scheme for more accurate device simulations.
• To enhance the predictive power of computational models for organic semiconducting devices.

Main Methods:

• Developed a scheme that tabulates simulation results from small-scale, off-lattice models.
• Corrected simulation data for finite size effects.
• Utilized tabulated mobility values to solve drift-diffusion equations for device characteristics.

Main Results:

• The proposed scheme was tested on DPBIC, a high-performance hole conductor for organic light-emitting diodes (OLEDs).
• Achieved good agreement between simulated and experimentally measured current-voltage characteristics.
• Validated the model's accuracy across different film thicknesses and temperatures.

Conclusions:

• The novel tabulation scheme offers a more robust alternative to traditional analytic expressions in drift-diffusion modeling.
• This method enhances the accuracy of organic semiconductor device simulations, particularly for state-of-the-art materials.
• The findings contribute to more reliable optimization of organic electronic devices like OLEDs.