Manufacturing of High-Efficiency Perovskite Solar Cells via Coupled Ion Source and Magnetron Discharges

该奖项支持基础研究，这些研究贡献了新的知识，使高效钙钛矿太阳能电池的制造成为可能，促进清洁能源的产生和使用，从而促进国家繁荣。钙钛矿太阳能电池是一种新兴的光伏器件，最近实现了超过25%的电能转换效率。钙钛矿型太阳能电池的一个关键部件是一种约100纳米厚的透明导电氧化物薄膜，它作为顶部电极收集光电流，同时允许光线通过。顶部电极下面的钙钛矿层是热敏的，需要在室温下沉积透明导电膜。然而，通过常规磁控溅射在室温下生长的氧化物薄膜-用于制造薄膜的标准工业技术-具有非晶态结构，导致导电性和光学透过率较低。这一挑战已经成为限制钙钛矿太阳能电池能量转换效率的关键障碍。该项目推进了等离子体放电的知识，使离子束增强型软溅射能够在室温下生长高度透明和导电的氧化物薄膜，显著提高太阳能电池的效率和性能。可再生能源的广泛使用支持了可持续经济并解决了全球环境问题。该项目为研究生和本科生整合了多学科研究和培训活动，并为他们未来的高技能劳动力做好准备。除了先进的制造，该项目还推动了等离子体物理领域的发展。该奖项还支持NSF的等离子体科学与工程领先创新生态系统(ECLIPSE)计划。高透明度和导电性的氧化物薄膜，如铟-锡-氧化物(ITO)，具有在经典物理气相沉积的低温非相平衡条件下无法形成的多晶结构。本研究旨在验证离子束与表面原子的相互作用在原子尺度上等同于局域加热的假设。实现有效的离子-原子相互作用需要克服科学障碍，以创造高密度、软、低能量的离子束，并有效地与磁控溅射相耦合。这一研究填补了在耦合等离子体放电作用下离子束和溅射原子的能量分布的知识空白。研究小组对束流等离子体源和磁控溅射进行了自洽的单元内粒子蒙特卡罗模拟，开发了一个模型来阐明相互增强的离子-薄膜和离子-目标相互作用，建立了等离子体参数与所产生的薄膜微结构和性能之间的关系，并展示了高效钙钛矿型太阳能电池。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award supports fundamental research that contributes new knowledge to enable the manufacturing of high-efficiency perovskite solar cells, promoting the generation and use of clean energy thus advancing national prosperity. Perovskite solar cells are emerging photovoltaic devices and have recently achieved power conversion efficiencies exceeding 25 percent. A critical component of perovskite solar cells is a transparent conductive oxide thin film of about 100 nanometer thickness, which acts as the top electrode to collect the photocurrent while allowing light to pass through. The perovskite layer underneath the top electrode is heat-sensitive and demands room-temperature deposition of the transparent conductive film. However, oxide thin films grown at room temperature by conventional magnetron sputtering – the standard industrial technology used for manufacturing thin films – have amorphous structures that result in poor electrical conductivity and low optical transmittance. This challenge has become a critical barrier limiting the energy conversion efficiencies of perovskite solar cells. This project advances the knowledge of plasma discharges to enable ion-beam-enhanced soft sputtering, which permits room-temperature growth of highly transparent and conductive oxide thin films that significantly enhance solar cell efficiency and performance. The broad use of renewable energy supports a sustainable economy and addresses global environmental concerns. This project integrates multidisciplinary research and training activities for graduate and undergraduate students and prepares them for a highly skilled future workforce. Besides advanced manufacturing, the project advances the field of plasma physics. This award also supports NSF's ECosystem for Leading Innovation in Plasma Science and Engineering (ECLIPSE) program.Highly transparent and conductive oxide thin films, such as indium-tin-oxide (ITO), have polycrystalline structures that could not be formed under off-phase-equilibrium conditions at low temperatures in classical physical vapor deposition. This research aims to validate the hypothesis that the interactions of an ion beam with the surface atoms are equivalent to localized heating at the atomic scale. Realizing effective ion-atom interactions requires overcoming the scientific barriers to creating a high-density soft low energy ion beam that is effectively coupled with magnetron sputtering. This research fills the knowledge gap on the energy distributions of the ion beam and the sputtered atoms under the coupled plasma discharges. The research team performs self-consistent particle-in-cell Monte Carlo simulations of the beam plasma source and magnetron sputtering, develops a model to elucidate the mutually enhanced ion-film and ion-target interactions, establishes the relationships between the plasma parameters and the resulting film microstructures and properties, and demonstrates high-efficiency perovskite solar cells.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.