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

非技术摘要：薄膜卤化物钙钛矿半导体已成为许多电子应用和太阳能转换的改变游戏规则的材料。Peroxide半导体由地球上丰富的元素组成，能够实现与Si和GaAs等传统半导体相当的高性能。然而，人们仍然很少了解如何生长薄膜单晶，这可能有助于导致这类材料的最大潜力。该项目由NSF材料研究部的固态和材料化学计划资助，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混合卤化物钙钛矿的精确控制薄膜沉积。这项基础研究使下一代薄膜钙钛矿量子应用，设计师多层膜，高速晶体管的实现成为可能，并指导稳定和低成本卤化物钙钛矿太阳能电池的开发。为了补充技术项目，协调的外联和教育工作扩大了“可持续能源和太阳能修补匠空间”讲习班，将“衍射的魔力”的新单元纳入密歇根州立大学校园的能源实践教育。此外，研究人员还举办了年度艺术竞赛，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最高性能卤化物钙钛矿电子和量子器件的广泛应用。 该项目由NSF材料研究部的固态和材料化学计划资助，进一步了解卤化物钙钛矿外延薄膜和超晶格的自下而上合成，具有受控的顺序和特性。与它们的氧化物类似物相比，卤化物钙钛矿体系界面处的涌现现象的研究还不够深入和充分。因此，对晶体有序、取向、应变和量子限制的控制是优化这些卤化物钙钛矿材料中的能量迁移的基础，用于下一代高性能光致发光、光电子和量子简并二维电子系统。采用气相生长，研究人员探索并揭示了钙钛矿薄膜的异质外延生长模式，这些模式还可以使用实时和原位衍射技术制造量子限制多层膜，这些技术针对绝缘和半导体衬底上的生长进行了优化。建立了调整外延膜和量子威尔斯的晶相、化学计量、应变和掺杂分布的路线，以在高质量的二维电子系统中实现电子多体相，并确定结构和量子特性之间的联系，从而指导未来的器件开发。为了补充该技术项目，协调的外展和教育工作扩大了“可持续和太阳能修补匠空间”研讨会的范围，纳入了“衍射的魔力”的新模块，用于密歇根州立大学校园的实际能源教育。此外，研究人员还举办了年度艺术竞赛，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最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NSF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.