Thin Film Photovoltaic Technologies

Thin film photovoltaic technologies encompass a class of solar-energy converters in which light-absorbing semiconductor layers are deposited at micrometre or sub-micrometre thicknesses onto supporting substrates. Compared with crystalline silicon, these devices offer advantages in minimised material use, potential for flexible form factors and compatibility with large-area, low-cost manufacturing. Key absorber materials include chalcogenides (such as CdTe, Cu(In,Ga)Se₂ and emerging kesterites), metal halide perovskites, antimony chalcogenides (Sb₂Se₃, Sb₂S₃) and tin-based compounds (SnS, SnSe). Performance hinges on precise control of film crystallinity, grain orientation, interface quality and defect populations, as well as on optimised band alignment and carrier transport across heterojunctions. Recent progress has driven efficiencies of mature thin-film modules above 20 %, while novel absorber systems have progressed from early proof-of-concept to stable, above-10 % devices. The continued evolution of deposition techniques—ranging from vapour transport and sputtering to solution processing—and of defect-passivation strategies underscores the global significance of thin-film photovoltaics for scalable, sustainable energy generation.

Research from Nature Portfolio

Recent studies have demonstrated the impact of nanostructuring and interface engineering on antimony selenide absorbers. One work achieved a record 9.2 % efficiency by constructing Sb₂Se₃ nanorod arrays with core-shell architecture and preferred [001] orientation, thereby enhancing light absorption and carrier extraction. A complementary investigation developed a vapour transport deposition method for Sb₂Se₃ thin films, yielding improved crystallinity and reduced deep-level defect density, and producing CdS/Sb₂Se₃ solar cells with 7.6 % power-conversion efficiency. More recently, optical deep-level transient spectroscopy has revealed the nature of three dominant trap states in Sb₂S₃, confirming the tolerance of its quasi-one-dimensional ribbon structure to certain defects and providing guidance on mitigating recombination centres to raise open-circuit voltage.

Thin Film Photovoltaic Technologies publication trend

The graph below shows the total number of articles in thin film photovoltaic technologies across all publications each year (not limited to Nature Index journals).

Technical terms

Absorber layer: The semiconductor film that absorbs photons and generates charge carriers.

Heterojunction: An interface between two dissimilar semiconductors used to separate and extract photogenerated charges.

Bandgap: The energy difference between the valence and conduction bands, determining the spectral range of light absorption.

Charge carrier recombination: The process by which electrons and holes annihilate, reducing photocurrent and voltage.

Defect passivation: Strategies to neutralise electronic trap states in a semiconductor to minimise non-radiative recombination.

Space-charge region: A depletion zone at a p–n or semiconductor–junction interface where an internal electric field separates charge carriers.

References

1. Improved carrier collection efficiency in CZTS solar cells by Li‐enhanced liquid‐phase‐assisted grain growth. EcoEnergy (2024).
2. Upper efficiency limit of Sb 2 Se 3 solar cells. Joule (2024).
3. Identifying the relationships between subsurface absorber defects and the characteristics of kesterite solar cells. Carbon Energy (2023).
4. 9.2%-efficient core-shell structured antimony selenide nanorod array solar cells. Nature Communications (2019).
5. Vapor transport deposition of antimony selenide thin film solar cells with 7.6% efficiency. Nature Communications (2018).
6. Revealing composition and structure dependent deep-level defect in antimony trisulfide photovoltaics. Nature Communications (2021).