RII Track-4: Low-temperature Laser Sintering and Melting of Semiconductors Through Selective Excitation of Soft Phonons

RII Track-4：通过软声子的选择性激发实现半导体的低温激光烧结和熔化

• 批准号: 2033424
• 负责人: Yan Wang
• 金额: $ 27.45万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2033424&HistoricalAwards=false
• 关键词: RII; Track; Low; temperature; Laser

Sintering and melting has become an integral processing step in consolidating semiconductor powders into compact engineering components. Laser sintering and melting stands out among processing options due to its high throughput, controllability, and natural ability to 3D print components. However, conventional laser processes typically heat materials to such high temperatures that the target region fully or partially melts, which can damage the sintered region and its surroundings due to overheating. This project aims to melt and sinter semiconductors at a reduced temperature by exploiting ultrafast laser-material interactions at the electronic and atomic levels. Complementary experimental-computational studies leveraging the advanced laser systems at the University of Nebraska, Lincoln (UNL) will be conducted to understand the dynamics of atoms in semiconductors under laser irradiation. Successful completion of this project will improve 3D printing technologies for various modern applications that rely on nanocrystalline semiconductors, such as solar cells and thermoelectric materials. This project will improve laser manufacturing education at the University of Nevada, Reno (UNR) through the development of innovative K-12 programs and undergraduate/graduate-level curricula. The ultrafast laser manufacturing techniques acquired through this project will also enhance Nevada and UNR’s competitiveness in additive manufacturing. The goal of this project is to achieve laser sintering and melting of semiconductors at significantly reduced temperatures compared to those in conventional laser processes, which will greatly reduce the adverse thermal effects (e.g., unwanted grain growth that degrades material properties) caused by prolonged high material temperature. To achieve this goal, three specific objectives will be pursued with complementary computational-experimental techniques: 1) identify the patterns of atomic motions that can effectively and efficiently trigger the melting of semiconductors using atomistic modeling; 2) elucidate the melting dynamics using quantum-mechanical calculations; and 3) demonstrate the proposed process using a dual-laser system that combines the strengths of the advanced ultrafast laser systems and the tunable-wavelength continuous laser systems at UNL. The successful completion of this project will lead to a low-temperature laser sintering and melting process with improved ability to control the microstructures and properties of 3D printed semiconductors, enabling 3D printing of high-quality thermoelectric modules, solar cells, electronic devices, etc. The acquired expertise in ultrafast laser processing, developed K-12 education programs on advanced manufacturing, and strengthened collaboration with an established laser manufacturing researcher from UNL will greatly strengthen the competitiveness of Nevada, UNR, and the principal investigator in the field of additive manufacturing and related applications like energy and electronics.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.

烧结和熔化已成为将半导体粉末合并到紧凑的工程组件中的组成部分。激光烧结和熔化由于其高吞吐量，可控性和3D打印组件的自然能力而引人注目。但是，常规的激光过程通常将材料加热到这样的高温，以至于目标区域完全或部分融化，从而损害了由于过热而损害烧结区域及其周围环境。该项目旨在通过利用电子和原子水平的超快激光材料相互作用来融化和烧结半导体。互补的实验计算研究利用内布拉斯加州大学林肯大学（UNL）的高级激光系统的研究，以了解激光照射下半导体原子的动力学。该项目的成功完成将改善依赖纳米晶半导体（例如太阳能电池和热电材料）的各种现代应用的3D打印技术。该项目将通过开发创新的K-12计划和本科/研究生级课程来改善内华达大学里诺（UNR）的激光制造教育。通过该项目获得的超快激光制造技术还将增强内华达州和UNR在添加剂制造方面的竞争力。该项目的目的是与常规激光过程相比，在温度显着降低的半导体上实现激光烧结和熔化，这将大大降低由延长的高材料温度延长引起的不良热效应（例如，不需要的晶粒生长）。为了实现这一目标，将通过完整的计算实验技术实现三个特定目标：1）确定可以使用量子力学计算来阐明融化动力学的原子运动模式； 3）使用双激光系统演示提出的过程，该系统结合了UNL的高级超快激光系统和可调波长连续激光系统的优势。该项目的成功完成将导致低温激光烧结和融化过程，并提高了控制3D印刷半导体的微观结构和性能的能力，从而可以3D打印高质量热电模块的3D打印，以实现超级工具，电子设备等，以实现超级工艺的培养，并在超级企业方面进行了培养，并在超级工艺方面进行了培养，并在超级企业中进行了培养，并在超级工艺方面进行了培养，并在超级工艺方面进行了培养，并在超级工艺方面进行了专业化，并在超级工艺方面进行了综合，并具有综合性的k-12 k-12 UNL的激光制造研究人员将极大地增强内华达州，UNR和添加剂制造领域的主要研究人员的竞争力以及能源和电子等相关应用领域。这项奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查审查标准来通过评估来通过评估来获得支持的。