Collaborative Research: Fundamental Studies of Carrier Selective Passivating Contacts for Efficient Photovoltaic Devices using Laser Processing and Atomic Resolution Interfaces

合作研究：利用激光加工和原子分辨率接口对高效光伏器件的载流子选择性钝化接触进行基础研究

• 批准号: 2005057
• 负责人: Ajeet Rohatgi
• 金额: $ 20万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2005057&HistoricalAwards=false
• 关键词: Collaborative; Research; Fundamental; Studies; Carrier

Nontechnical:Solar cells convert sunlight to electricity and have several unique advantages. They operate without monitoring, do not emit pollution, and can be made from earth-abundant and non-toxic materials. The use of solar energy is rapidly growing, but it still accounts for only a small fraction of electricity production. To increase their share of the energy market, the cost of making and operating solar cells must be decreased and their efficiency must increase. Carrier-selective passivating contacts hold the promise of doing just that. Such contacts increase cell efficiency by reducing electrical losses at the interface between the layer of a solar cell that absorbs light and the metal contacts that extract electrical current. This project will use a unique way to improve the fundamental understanding and control of loss mechanisms in solar cells with such contacts. Laser processing provides a way to electrically activate carrier-selective passivating contacts by selectively depositing laser energy into a selected layer with fine control at high speed. This process has the potential to increase the power conversion efficiency of solar cells while maintaining low temperature and high throughput, thereby decreasing the cost per kilowatt-hour of energy produced. The generated knowledge will improve various types of solar power generating as well as other electronic and photonic devices. The proposal brings together an experienced multidisciplinary team with expertise in solar cell fabrication, laser processing, and atomic-scale characterization. The PIs will engage in extensive outreach to local high schools, museums, and libraries. The economic impact will be amplified through work with solar cell manufacturing companies. This project will help society meet its future energy needs using fewer resources at a reduced cost while preventing pollution and climate change.Technical:This project encompasses carrier-selective passivating contact development, photovoltaic device fabrication, laser processing, and imaging at the atomic level using transmission electron microscopy. Carrier-selective passivating contacted (CSPC) devices are a promising next generation technology for photovoltaic devices because they eliminate the two primary loss mechanisms: the direct metal contact to silicon and dopant diffusion into the bulk. A fundamental understanding of the interface quality, dopant type, dopant activation (and potential diffusion), tunneling mechanism, and the effect of the passivation layer is still lacking. Through a combination of device modeling, fabrication and laser processing experiments, and transmission electron microscopy studies, the quantitative degree of CSPC band bending and band gaps; effect of thermal crystallization on optical absorption, implied open-circuit voltage and defect content; and independent control of dopant activation, crystallization, grain growth, and dopant diffusion will be investigated to provide the photovoltaic industry a better understanding of CSPC for is manufacturing adoption. The novelty of the aim of this study lies in the use of pulsed laser processing of CSPC to provide a non-contact way of annealing the device with surface heating only. This work will provide a fundamental understanding of the interface properties at the atomic and nanoscale level and relate these studies to the optical and electronic properties as well as to device performance of a full-area state-of-the-art CSPC device. This project will have a broad impact by training an interdisciplinary, interuniversity, and diverse team of graduate and undergraduate students across two universities.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.

非技术性：太阳能电池将太阳光转化为电能，有几个独特的优点。它们在没有监测的情况下运行，不排放污染，并且可以由地球上丰富的无毒材料制成。太阳能的使用正在迅速增长，但它仍然只占电力生产的一小部分。为了增加其在能源市场的份额，必须降低太阳能电池的制造和运行成本，并提高其效率。载流子选择性钝化接触有望做到这一点。这种接触通过减少太阳能电池的吸收光的层与提取电流的金属接触之间的界面处的电损耗来提高电池效率。该项目将使用一种独特的方法来提高对具有这种接触的太阳能电池中损耗机制的基本理解和控制。激光处理提供了一种通过以高速精细控制将激光能量选择性地沉积到选定层中来电激活载流子选择性钝化接触的方式。这一过程有可能提高太阳能电池的功率转换效率，同时保持低温和高产量，从而降低每千瓦时能源的成本。产生的知识将改善各种类型的太阳能发电以及其他电子和光子设备。该提案汇集了一个经验丰富的多学科团队，拥有太阳能电池制造，激光加工和原子级表征方面的专业知识。PI将广泛接触当地高中、博物馆和图书馆。通过与太阳能电池制造公司的合作，经济影响将得到放大。该项目将帮助社会以更少的资源和更低的成本满足未来的能源需求，同时防止污染和气候变化。技术：该项目包括载流子选择性钝化接触开发，光伏器件制造，激光加工和使用透射电子显微镜在原子水平上成像。载流子选择性钝化接触（CSPC）器件是用于光伏器件的有前途的下一代技术，因为它们消除了两种主要的损耗机制：与硅的直接金属接触和掺杂剂扩散到体中。对界面质量、掺杂剂类型、掺杂剂激活（和潜在扩散）、隧穿机制和钝化层的影响的基本理解仍然缺乏。通过器件建模、制作和激光加工实验以及透射电镜研究，定量地研究了CSPC的带弯曲程度和带隙，热晶化对光吸收、开路电压和缺陷含量的影响，并对CSPC的能带结构进行了分析。以及独立控制掺杂剂活化、结晶、晶粒生长和掺杂剂扩散将被调查，以提供光伏产业更好地了解CSPC的是制造采用。本研究目的的新奇在于使用CSPC的脉冲激光加工提供仅用表面加热的非接触式退火装置。这项工作将提供一个基本的理解，在原子和纳米级的界面特性，并与这些研究的光学和电子性能，以及设备性能的全面积国家的最先进的CSPC设备。该项目将通过培养跨学科、跨大学、由两所大学的研究生和本科生组成的多元化团队产生广泛的影响。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。