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Development of New Materials and Manufacturing Processes

• Multifunctional Nanomaterials for Photon Management and Surface Passivation
• Atmospheric Pressure Chemical Vapor Deposition of Doped Polysilicon for TOPCon Photovoltaic Cells
• Passivating, Carrier-Selective Contacts Formed by Atomic Layer Deposition of Metal Oxides
• High Conductivity Metallization Formed by Photonic Curing and Sintering of Metal Pastes

Metrology for Process Control and Quality Assurance in Manufacturing

• Spatially-Resolved Characterization of Photovoltaic Cells
• Comprehensive, High-Throughput Metrology for Photovoltaic Cell Manufacturing

Multiscale and Multimodal Metrology to Advance Degradation Science

• Spatial and Semantic Performance Analysis of Photovoltaic Module Performance
• Multiscale Characterization of Materials Degradation in Photovoltaics
• Data-Driven, Accelerated Screening of Metal Contact Degradation Susceptibility
• Evaluating Materials Degradation in Electronic Circuits via Multimodal, In Situ Metrology

Data-Centric Approaches to Promote Energy Affordability and Resilience

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Development of New Materials and Manufacturing Processes

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Multifunctional Nanomaterials for Photon Management and Surface Passivation

While dielectric nanostructures effectively enhance optical absorption in semiconductors by trapping light and reducing front-surface reflection, surfaces often introduce competing losses. A major culprit is charge carrier recombination due to surface defect states. This research aims to address both optical and electrical losses simultaneously via engineered nanomaterials.

In collaboration with Brookhaven National Laboratory, we demonstrated that strategically designed nanomaterials can serve a dual purpose: photon management and surface passivation. Utilizing directed self-assembly, we engineered ordered arrays of aluminum oxide (Al₂O₃) nanostructures in various tunable geometries, including lamellae, nanoholes, and nanopillars.

Scanning electron microscopy (SEM) images of aluminum oxide nanostructures formed on silicon wafers via directed self-assembly.

Relevant Projects

• Surface Passivation of Nanostructured Silicon Surfaces to Reduce Optical and Recombination Losses, U.S. Dept. of Energy Office of Science User Facilities, 2019-2021.

Relevant Publications

• Hossain, M.J., Sun, M., Doerk, G., Kik, P.G., Davis, K.O., 2021. Self-assembled multifunctional nanostructures for surface passivation and photon management in silicon photovoltaics. Nanophotonics 10, 4611–4621. https://doi.org/10.1515/nanoph-2021-0472

Atmospheric Pressure Chemical Vapor Deposition of Doped Polysilicon for TOPCon Photovoltaic Cells

The Challenge

Tunnel oxide passivated contact (TOPCon) photovoltaic cells have emerged as the new dominate cell architecture on the market, rapidly displacing passivated emitter and rear cells (PERC) due to efficiency gains. These gains are achieved by reducing charge carrier recombination at the boundary between the active semiconductor and the metal contacts. This improved interface relies on the formation of a doped polycrystalline films on top of a very thin (1-2 nm) silicon oxide layer. Traditionally, this process is carried out using vacuum-based deposition systems, like low pressure chemical vapor deposition (LPCVD) and plasma-enhanced CVD.

Our Approach

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Findings

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Takeaways