Vapor-Phase Epitaxy of Single-Domain Halide Perovskites for Quantum Applications

非技术总结：薄膜卤化物钙钛矿半导体已经成为许多电子应用和太阳能转换的改变游戏规则的材料。钙钛矿半导体由地球上丰富的元素组成，能够实现与传统半导体（如Si和GaAs）相当的高性能。然而，人们对如何生长单晶薄膜仍然知之甚少，而单晶薄膜可以帮助这类材料发挥最大的潜力。该项目由美国国家科学基金会材料研究部固态和材料化学项目资助，扩展了卤化物钙钛矿单晶生长动力学的知识。研究人员研究了无机和杂化卤化物钙钛矿的精确控制薄膜沉积。这项基础研究能够实现下一代薄膜钙钛矿量子应用，设计多层，高速晶体管，并指导稳定和低成本卤化物钙钛矿太阳能电池的发展。作为技术项目的补充，一项协调的推广和教育工作扩大了“可持续和太阳能修补匠空间”研讨会，其中包括“衍射的魔力”的新模块，用于在密歇根州立大学校园进行实际的能源教育。此外，研究人员还举办了一年一度的艺术比赛，以提高人们对创新材料科学研究的认识。这项研究最终使美国更接近于高性能卤化物钙钛矿电子和量子器件的广泛应用。技术概述：该项目由美国国家科学基金会材料研究部固态和材料化学项目资助，进一步了解了自下而上合成有序和性能可控的卤化物钙钛矿外延薄膜和超晶格的方法。与它们的氧化物类似物相比，卤化物钙钛矿体系界面突现现象的研究一直未得到充分的探索和开发。因此，对晶体顺序、取向、应变和量子约束的控制是优化这些卤化物钙钛矿材料中能量迁移的基础，这些材料用于下一代高性能光伏、光电子和量子简并二维电子系统。采用蒸汽生长，研究人员探索并揭示了钙钛矿薄膜的异质外延生长模式，该模式还可以使用实时和原位衍射技术在绝缘和半导体衬底上优化生长，从而制造量子限制多层。建立了定制外延薄膜和量子阱的晶体相、化学计量学、应变和掺杂谱的途径，以实现高质量二维电子系统中的电子多体相，并确定结构与量子特性之间的联系，从而指导未来的器件开发。作为技术项目的补充，一项协调的推广和教育工作扩大了“可持续和太阳能修补匠空间”研讨会，其中包括“衍射的魔力”的新模块，用于在密歇根州立大学校园进行实际的能源教育。此外，研究人员还举办了一年一度的艺术比赛，以提高人们对创新材料科学研究的认识。这项研究最终使美国更接近于高性能卤化物钙钛矿电子和量子器件的广泛应用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical Summary:Thin film halide perovskite semiconductors have emerged as game-changing materials for many electronic applications and for solar energy conversion. Perovskite semiconductors are composed of earth-abundant elements, and are capable of achieving high performance comparable to traditional semiconductors such as Si and GaAs. However, there is still very little understanding how to grow thin film single crystals that could help lead to the highest potential for this class of material. This project, funded by the Solid State and Materials Chemistry program in the Division of Materials Research at NSF, expands the knowledge of accessible single-crystal growth dynamics for halide perovskites. The researchers study precisely controlled thin-film deposition of inorganic and hybrid halide perovskites. This fundamental research enables the realization of next generation thin-film perovskite quantum applications, designer multilayers, high speed transistors, and guides the development of stable and low-cost halide perovskite solar cells. To complement the technical project, a coordinated outreach and educational effort expands "Sustainable- and Solar-Energy Tinker-Space" workshops to include new modules on "The Magic of Diffraction" for hands-on energy education on the Michigan State University campus. Additionally, the researchers develop an annual art competition to raise awareness of innovative Materials Science research. This research ultimately brings the U.S. closer to the widespread application of the highest performance halide perovskite electronics and quantum devices. Technical Summary:This project, funded by the Solid State and Materials Chemistry program in the Division of Materials Research at NSF, furthers the understanding of the bottom-up synthesis of halide perovskite epitaxial films and superlattices with controlled order and properties. Compared to their oxide analogues, the study of emergent phenomenon occurring at the interface for halide perovskite system has been underexplored and underexploited. Control over crystalline order, orientation, strain, and quantum confinement are therefore fundamental to the optimization of energy migration in these halide perovskite materials for the next generation high performance photovoltaics, optoelectronics and quantum degenerate two-dimensional electron systems. Employing vapor growth, the researchers explore and uncover heteroepitaxial growth modes of perovskite films that also enable the fabrication of quantum confined multilayers using real-time and in-situ diffraction techniques optimized for growth on both insulating and semiconducting substrates. Routes to tailoring the crystalline phase, stoichiometry, strain, and doping profiles of epitaxial films and quantum wells are established to realize electronic many-body phases in high-quality two-dimensional electron systems and determine the connection between structure and quantum properties that can guide future device development. To complement the technical project, a coordinated outreach and educational effort expands "Sustainable- and Solar-Energy Tinker-Space" workshops to include new modules on "The Magic of Diffraction" for hands-on energy education on the Michigan State University campus. Additionally, the researchers develop an annual art competition to raise awareness of innovative Materials Science research. This research ultimately brings the U.S. closer to the widespread application of the highest performance halide perovskite electronics and quantum devices.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.