Evaporation Technique Unlocks Record-Breaking 29.43% Efficiency in Perovskite-Silicon Tandem Solar Cells

Breakthrough in Solar Cell Manufacturing

Researchers have developed an innovative evaporation method for creating wide-bandgap perovskite solar cells that has achieved a remarkable 29.43% power conversion efficiency in tandem configurations with silicon cells. This advancement represents a significant leap forward in photovoltaic technology, demonstrating the potential for more efficient and stable solar energy harvesting through precise material deposition techniques.

Breakthrough in Solar Cell Manufacturing
The SCG Evaporation Strategy
Manufacturing Process and Material Specifications
Tandem Device Architecture and Performance
Advanced Characterization and Stability Assessment
Industrial Implications and Future Applications

The SCG Evaporation Strategy

The core innovation lies in the sequential co-evaporation growth (SCG) strategy, which enables the creation of highly oriented and stable perovskite films. Unlike traditional solution-based methods, this evaporation approach allows for better control over film morphology and crystallinity. The process involves simultaneous evaporation of three key precursors: formamidinium iodide (FAI), lead iodide (PbI₂), and cesium bromide (CsBr) at precisely controlled deposition rates of 2 Å/s, 2 Å/s, and 0.9 Å/s respectively.

What makes this method particularly revolutionary is the ability to maintain these deposition rates consistently while keeping the substrate temperature at 20°C and chamber pressure at approximately 1×10⁻⁶ mbar. The entire deposition process for the 600nm thick perovskite layer takes approximately 50 minutes, after which the films require no additional annealing – a significant advantage for industrial scaling., according to related news

Manufacturing Process and Material Specifications

The fabrication process begins with carefully cleaned ITO glass substrates that undergo UV-ozone treatment before receiving a nickel oxide (NiO) nanoparticle layer. The researchers utilized high-purity materials throughout, including 99.999% pure CsBr and 99.99% pure PbI₂ from Sigma-Aldrich, ensuring minimal impurities that could compromise device performance., according to industry news

Key differentiators from conventional methods include:, according to related news

Elimination of solvent-related defects common in solution processing
Superior control over film thickness and composition
Enhanced crystal orientation without post-deposition annealing
Better compatibility with industrial manufacturing workflows

Tandem Device Architecture and Performance

The perovskite-silicon tandem configuration demonstrates the practical application of this technology. The complete device stack includes:

TOPCon silicon bottom cell with ITO treatment
NiO hole transport layer
600nm evaporated perovskite absorber
15nm C₆₀ electron transport layer
10nm SnO₂ buffer layer deposited via atomic layer deposition
80nm ITO transparent electrode
350nm silver grid with 100nm LiF protective layer

Performance testing revealed exceptional results, with the champion device achieving 29.43% efficiency on a 1 cm² active area. The measurement conditions followed rigorous standards, using SINUS-220 characterization equipment under simulated AM1.5G illumination at 100 mW/cm². The scanning parameters were optimized at 100 mV/s with 10 mV steps and 200 ms delay time to ensure accurate performance assessment., according to market analysis

Advanced Characterization and Stability Assessment

The research team employed comprehensive analytical techniques to validate their findings. Synchrotron-based grazing-incidence wide-angle X-ray scattering (GIWAXS) provided insights into the crystal structure and orientation, while cross-sectional SEM imaging revealed the well-defined layer interfaces crucial for efficient charge transport., as detailed analysis

Stability testing followed the ISOS-L-3 protocol under demanding conditions: 25°C temperature with approximately 85% relative humidity. The devices maintained performance thanks to careful encapsulation using UV-curable epoxy in nitrogen environments. Additional accelerated aging tests with elevated temperatures further confirmed the robustness of the evaporated perovskite films.

Industrial Implications and Future Applications

This evaporation-based manufacturing approach addresses several critical challenges in perovskite solar cell production. The method offers superior reproducibility and scalability compared to solution-based techniques, while the demonstrated stability under various environmental conditions meets key requirements for commercial deployment.

The successful transfer of the SCG strategy from single-junction to tandem configurations highlights its versatility and potential for integration with existing silicon photovoltaic manufacturing lines. As the solar industry continues to push efficiency boundaries, this evaporation technique provides a viable pathway toward achieving the >30% efficiency targets that have long been the holy grail of photovoltaic research.

With further optimization and scaling, this technology could significantly reduce the levelized cost of solar electricity while maintaining the high performance standards required for widespread adoption in both utility-scale and distributed generation applications.