Optical modeling and optimizations of Cu₂ZnSnSe₄ solar cells using the modified transfer matrix method

Area of Science:

• Materials Science
• Renewable Energy
• Optical Engineering

Background:

• Kesterite Cu2ZnSnSe4 solar cells are a promising photovoltaic technology.
• Accurate optical modeling is crucial for device performance optimization.
• Interface roughness can impact optical response in thin-film solar cells.

Purpose of the Study:

• To simulate and optimize the optical response of kesterite solar cells using the Modified Transfer Matrix Method (MTM).
• To investigate the effect of transparent conductive oxide (TCO) and cadmium sulfide (CdS) layer thicknesses on device photocurrent.
• To identify optimal TCO/CdS layer combinations for enhanced solar cell efficiency.

Main Methods:

• Employing the Modified Transfer Matrix Method (MTM) for optical response simulation.
• Partially accounting for scattering effects from interface roughness.
• Systematically varying TCO (iZnO + ITO) thickness from 50 to 1200 nm.
• Systematically varying CdS buffer layer thickness from 0 to 100 nm.

Main Results:

• The MTM simulation provides a fast and computationally inexpensive approach.
• Optimal TCO and CdS layer thicknesses were determined to locally maximize photocurrent.
• Theoretical predictions were qualitatively validated by experimental data.

Conclusions:

• The MTM is an effective tool for optimizing kesterite solar cell optical design.
• Specific TCO/CdS thickness combinations can significantly enhance device photocurrent.
• This research provides a pathway for improving the efficiency of kesterite solar cells through optical engineering.