UNS: Collaborative Research: 30%-Efficient III-V/Silicon Tandem Solar Cells

UNS：%20协作%20研究：%2030%-高效%20III-V/硅%20串联%20太阳能%20电池

• 批准号: 1509864
• 负责人: Zachary Holman
• 金额: $ 14.09万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1509864&HistoricalAwards=false
• 关键词: UNS; Collaborative; Research; 30; Efficient

PI: Minjoo Larry Lee / Zachary C. HolmanProposal Number: 1509687/ 1509864The sun represents the most abundant potential source of sustainable energy on earth. Currently, solar cells based on crystalline silicon materials dominate the photovoltaics market for production of electricity from the sun because they offer the highest solar energy conversion efficiency at the lowest manufacturing cost. However, to accelerate the penetration of solar energy in the renewable electricity market, the solar energy conversion efficiency of silicon-based solar cells must ultimately increase beyond its practical limit of 24%. The goal of this project is develop a silicon-based solar cell which contains Group III and V elements from the Periodic Table, arranged in layers which have the potential to increase the solar energy conversion efficiency to 30%. The fundamental science underlying the performance of this the III-V/silicon tandem cell will be used to develop the best strategy for eventual manufacture. As part of the educational activities of this project, the principal investigators will be actively involved in an outreach program that seeks to broaden the participation of under-represented groups in engineering by using solar research as a platform for involvement in both technical and career-development sessions at Veterans meetings and the Society of Hispanic Professional Engineers conference.Photovoltaic devices that contain multiple p-n junctions are currently the only route to achieve solar energy conversion efficiencies that exceed the Shockley-Queisser single p-n junction limit that caps the theoretical performance of crystalline silicon solar cells currently in commercial use. The overall goal of this proposed research is to develop a fundamental understanding of two-terminal tandem solar cell performance through controlled growth of Group III-V elements on silicon. The fabrication strategy is guided by fundamental studies and is designed to optimize the material and device architecture to achieve 30% solar energy conversion efficiency, which is beyond the 24% practical limit of single-junction crystalline silicon solar cells. Towards this end, the model Group III-V material selected for study is GaAsP, since it has a direct and tunable bandgap, and can be grown on a transparent, compositionally graded buffer on a GaP/Si template. The bottom cell of the tandem device will be based on an amorphous silicon/crystalline silicon heterojunction solar cell, where the front amorphous silicon layers will be replaced with the GaP template layer upon which the top cell is grown. The research plan has three objectives. The first objective is to understand and control the formation of threading dislocations in the GaAsP absorber, and to develop optimized window and back-surface field layers for the top cell that will both increase transmission into the GaAsP absorber and reduce surface recombination. The second objective is to understand and improve the passivation of GaP on silicon and the transport of electrons across the conduction band offset. The third objective is to maximize the conversion of infrared light into current in the bottom cell by designing single-side light-trapping textures and dielectric/metal rear reflectors, and then tune the thicknesses, doping densities, and bandgaps of the III-V supporting layers to both form a recombination junction between the sub-cells and match their currents. The research outcomes will advance fundamental scientific understanding of multi-junction solar cell performance while developing fabrication strategies that will enable for scalable industrial manufacture of devices potentially capable of delivering 30% solar energy conversion efficiency. The principal investigators will also use the research outcomes to enhance instructional materials in photovoltaics course offerings at Yale University and Arizona State University.

PI：Minjoo Larry Lee / Zachary C. HolmanPropossal编号：1509687 /1509864 The Sun是地球上可持续能源的最丰富潜在来源。 目前，基于结晶硅材料的太阳能电池主导了光伏市场从太阳生产电力的市场，因为它们以最低的制造成本提供了最高的太阳能转化效率。 但是，为了加速太阳能在可再生电力市场中的渗透，基于硅的太阳能电池的太阳能转化效率最终必须超过其实际限制24％。 该项目的目的是开发一个基于硅的太阳能电池，该太阳能电池包含III组和V元素的元素，并以层次排列，该层有可能将太阳能转化效率提高到30％。 IIII-V/硅串联细胞的基础科学将用于制定最终制造的最佳策略。 作为该项目的教育活动的一部分，首席研究人员将积极参与一项外展计划，该计划旨在通过使用太阳能研究作为参与技术和职业发展的平台来扩大代表性不足的团体在工程中的参与超过冲击式盖塞人单P-N连接极限的效率限制了目前在商业用途中的晶体硅太阳能电池的理论性能。 这项拟议的研究的总体目标是通过控制硅III-V元素的控制生长来对两端串联太阳能细胞性能进行基本理解。制造策略以基本研究为指导，旨在优化材料和装置架构以实现30％的太阳能转化效率，这超出了单连接晶体硅太阳能电池的24％实际限制。为此，选择用于研究的模型组III-V材料是GAASP，因为它具有直接和可调的带隙，并且可以在GAP/SI模板上在透明的构图分级缓冲液上生长。串联设备的底部电池将基于无定形硅/晶体硅异轴孔牢房，在该单元中，前无定形硅层将用缝隙模板层代替，顶部细胞在上面生长的间隙模板层。 研究计划有三个目标。第一个目的是了解和控制GAASP吸收器中螺纹位错的形成，并为顶部细胞开发优化的窗口和后表面层，以增加向GAASP吸收器的传输并减少表面重组。第二个目标是了解和改善硅上的间隙和电子在传导带偏移中的传输。 第三个目标是通过设计单面光捕获纹理和介电/金属后反射器，将红外光转化为底部电池的电流，然后调整厚度，兴奋剂密度以及III-V支撑层的带盖以在子细胞和匹配的情况之间形成重新组合连接。研究成果将提高对多开关太阳能电池性能的基本科学理解，同时制定制造策略，以实现可扩展的工业制造设备的可扩展工业制造，该设备可能能够提供30％的太阳能转化效率。 首席研究人员还将利用研究成果来增强耶鲁大学和亚利桑那州立大学光伏课程的教学材料。