Black Silicon Photovoltaics

迫切需要努力降低可再生能源的成本，以应对气候变化的最严重影响。增长最快的可再生能源技术是光伏(PV)，它将在未来几十年占全球发电能力的30%。硅光伏目前占市场份额的90%以上，这是一项经过验证的技术，重大的技术改进将确保进一步降低价格和增加部署。电池能量转换效率的提高是降低太阳能成本的关键驱动因素，本提案旨在通过开发工业兼容的硅太阳能电池的光学增强、表面钝化和发射极形成技术来实现这一目标。作为该项目的一部分，开发的方法将应用于基于单晶硅和多晶硅的领先太阳能电池技术。对于c-Si，这是一种后结(RJ)架构，也称为交指背接单元，而对于MC-Si，这是一种前结(FJ)架构。为了增强RJ电池技术，其中p-n结位于电池的后部，不受前表面毛化的影响，方法是使用基于溶液的毛化技术，导致光学黑色硅表面。对于FJ单元结构的情况，其中必须考虑在前表面与织构一起形成的p-n结，将研究气相过程。在为RJ和FJ太阳能电池开发有效的减反射表面后，挑战是将光子捕获的增益转化为电池效率的提高。要做到这一点，必须研究表面的电学性质，并开发方法来减轻由于毛化过程而导致的任何电学退化。该项目的独特之处在于共同解决电池的光学和电学特性，通过这样做，旨在生产能够轻松集成到太阳能电池制造中的最佳纹理表面。南安普顿和牛津的项目团队将利用他们与德国Fraunhofer ISE和澳大利亚新南威尔士大学世界领先的研究机构的密切合作。这将使拟议的纹理技术能够在最先进的硅太阳能电池上进行演示，并提供在表征和加工方面的先进技术。这些合作还将促进向英国研究界的知识转移。这项提议的一个核心原则是为改善工业太阳能电池生产做出贡献。为此，双方建立了两个战略产业合作关系。首先，英国领先的太阳能电池工业工具制造商Tetreon Technologies将密切参与该项目，目标是随后开发出口到全球市场的工业设备和工艺。其次，天合光能是世界上最大的电池制造商之一，也是高效电池的行业领先者，它将提供对该项目旨在满足的市场和行业需求的洞察。他们将展示从电池到模块制造的工业环境中的成功工艺。通过这些合作，该项目将利用表面钝化和捕光互补领域的尖端专业知识来应对开发光伏技术的挑战。该项目将大大提高硅基太阳能电池和组件的效率，并通过与英国和国际公司的密切合作，使所进行的研究能够以新工具和新工艺的形式迅速得到利用，出口到全球太阳能行业。除了团队内部的专业知识外，其学术和行业网络也为创新和有影响力的研究计划提供了理想的基础。

Urgent efforts are required to reduce the cost of renewable energy in order to tackle the worst effects of climate change. The fastest growing renewable energy technology is photovoltaics (PV), which will account for 30% of global power generation capacity in the coming decades. Silicon PV, which currently accounts for more than 90% of the market, is a proven technology where significant technological improvements will ensure further price reductions and increased deployment. Improvement in cell power conversion efficiency is a key driving factor in reducing the cost of solar energy, which this proposal aims to achieve by developing industrially-compatible optical enhancement, surface passivation and emitter formation techniques for silicon solar cells.The methods developed as part of this project will be applied to the leading solar cell technologies based on mono- (c-Si) and multi-crystalline silicon (mc-Si). For c-Si, this is a rear junction (RJ) architecture also known as the interdigitated back contact cell, and for mc-Si, this is a front junction (FJ) architecture. To enhance the RJ cell technology, where the p-n junction is at the back of the cell and unaffected by the front surface texturing, the approach is to use a solution-based texturing technique that leads to optically black silicon surfaces. For the case of the FJ cell architecture, where formation of the p-n junction at the front surface alongside texturing has to be considered, gas-phase processes will be investigated. Upon developing effective antireflective surfaces for RJ and FJ solar cells the challenge becomes transferring the gain in photon capture to improvements in the efficiency of the cell. For this to take place the electrical properties of the surface must be studied, and methods developed to mitigate any electrical degradation due to the texturing processes. This project is uniquely positioned to address jointly the optical and electrical properties of the cells, and by doing so, aims to produce optimally textured surfaces that can be easily integrated into the manufacture of solar cells.The project teams at Southampton and Oxford will draw on their close collaborations with the world-leading research institutes at Fraunhofer ISE, Germany, and UNSW, Australia. This will enable the demonstration of the proposed texturing technology on state-of-the-art silicon solar cells, as well as providing access to advanced techniques in characterisation and processing. These collaborations will also promote knowledge transfer to the UK research community. A core principle of this proposal is to contribute to improving industrial solar cell production. For this, two strategic industrial collaborations have been established. Firstly Tetreon Technologies, the leading UK manufacturer of industrial tools for solar cell production, will be closely involved in the project, with the aim of subsequently developing industrial equipment and processes for export to the global market. Secondly Trina Solar, one of the world's largest cell manufacturers and the industrial leader in high efficiency cells, will provide insight into the market and industry needs that this project aims to address. They will demonstrate successful processes in an industrial environment from cell to module manufacture. Through these collaborations this project will leverage cutting edge expertise in the complementary areas of surface passivation and light trapping to tackle the challenge of developing photovoltaic technology. The project will deliver substantially improved efficiencies for silicon based solar cells and modules and, through close collaboration with UK and international companies, will allow the research undertaken to be rapidly exploited in the form of new tools and processes for export to the global solar industry. Alongside the expertise within the team, its academic and industrial networks form an ideal basis for the innovative and impactful research programme.