New Extraction Technique of In-Gap Electronic-State Spectrum Based on Time-Resolved Charge Extraction.

Area of Science:

• Materials Science
• Solid State Physics
• Photovoltaics

Background:

• In-gap electronic states, known as trap states, significantly impact solar cell performance.
• Accurate characterization of trap state density is crucial for optimizing photovoltaic devices.

Purpose of the Study:

• To develop a novel and reliable technique for extracting the density of trap state (DOS_T) distribution.
• To compare the proposed method with existing approaches for accuracy and computational efficiency.

Main Methods:

• Utilizing results from time-resolved charge extraction (TRCE) experiments.
• Developing a new analytical method based on the TRCE data.
• Establishing a relationship between the linearity of TRCE results and the type of DOS_T distribution.

Main Results:

• A new method for density of trap state (DOS_T) distribution extraction from TRCE data is presented.
• The derived method shows that linear TRCE results correspond to an exponential DOS_T distribution, and vice versa.
• The proposed technique demonstrates higher accuracy and reliability compared to Wang et al.'s method.

Conclusions:

• The novel TRCE-based method provides a more accurate and reliable approach for determining trap state density distribution.
• This technique is computationally less demanding than methods relying on space-charge-limited current (SCLC) experiments.
• The findings contribute to a better understanding and optimization of solar cell materials and performance.