Electrochemical Synthesis of Structurally Ordered, Magnetic Pt-Based Alloys for Magnetic Microdevices

硬磁材料在微制造工艺中的集成可能会导致具有改进功能的新型设备，例如新型存储介质概念或更有效的磁性微致动器。电镀方法将通过使用纯添加工艺来促进这些结构的制造，同时允许光刻图案的精确再现。本研究旨在实现电镀，等原子的Fe-Pt合金的生长和退火过程的基本理解，以生产在磁性微系统应用中有用的材料。具体而言，结构有序的Fe-Pt薄膜，微米和纳米结构与预定的晶体取向和大磁晶各向异性将被开发。特别是，在膜中的有序的tetraxylene结构的形成动力学将作为厚度，微观结构和内部应力的函数进行研究，并将通过在膜中引入成分梯度和通过使用合适的底层进行控制和优化。三元Fe-Mn-Pt合金将被开发以进一步增强各向异性，从而扩展可实现的性能范围。材料的磁响应将通过控制有序结构的微观结构和晶体取向来针对目标应用进行定制。将研究纳米尺寸或高纵横比的图案化结构内合金的成核和生长模式，以模拟未来的器件组件。相变和磁硬化在这样的限制结构将被分析为几何形状，结构尺寸，生长条件和底层的函数，以了解这些过程，并制定可行的合成和后处理条件能够实现感兴趣的属性。永磁体是磁性材料，一旦磁化就保持磁矩，并且本身成为有用的磁场源。它们在现代机械和电器中无处不在，例如电动机、通信设备以及计算机和数据库中的信息存储。永磁材料的进步可能使其功能扩展到微米和纳米级器件，可能导致杰出的技术创新;然而，合适的材料和生产方法尚未可用。该项目旨在将永磁材料与现有的微芯片制造方法相结合，最终实现磁性微尺度器件的生产。为了做到这一点，将研究Fe-Pt合金的形成和后处理，目的是实现即使在极低尺寸下也表现出高性能的材料。目标应用将包括新的信息存储技术和传感器和生物医学芯片的微尺度运动。除了这些技术方面，该项目将提供本科生研究实习，为学生提供培训和动力，以追求研究生学习，以及研究生的研究管理经验的机会。反过来，研究生在公司内部的实习将促进他们的科学和专业发展。

TECHNICAL SUMMARY:The integration of hard magnetic materials within microfabrication processes may lead to novel devices with improved functionalities, such as novel storage media concepts or more effective magnetic microactuators. Electroplating methods would facilitate the fabrication of these structures by using purely additive processes, while allowing accurate reproduction of lithographic patterns. This research seeks to achieve a fundamental understanding of the growth and annealing process of electroplated, equiatomic Fe-Pt alloys, in order to produce materials useful in magnetic microsystems applications. Specifically, structurally ordered Fe-Pt films, micro- and nanostructures with a predetermined crystal orientation and large magnetocrystalline anisotropy will be developed. In particular, the kinetics of formation of the ordered tetragonal structure in films will be studied as a function of thickness, microstructure and internal stresses, and will be controlled and optimized by introducing compositional gradients in the films and by using suitable underlayers. Ternary Fe-Mn-Pt alloys will be developed to further enhance anisotropy and thus extend the range of achievable properties. The materials' magnetic response will be tailored for the targeted application via control of the microstructure and crystallographic orientation of the ordered structure. Nucleation and growth modes of the alloys within patterned structures of nanometer size or with high aspect ratios will be investigated in order to model prospective device components. Phase transformation and magnetic hardening in such confined structures will be analyzed as a function of geometry, structure size, growth conditions and underlayers in order to understand such processes and to develop feasible synthesis and post-processing conditions capable to achieve the properties of interest. NON-TECHNICAL SUMMARY:Permanent magnets are magnetic materials that once magnetized maintain a magnetic moment and become themselves useful sources of magnetic fields. They are ubiquitous in modern machinery and appliances, such as electrical motors, communication devices and information storage in computers and data banks. Advances in permanent magnet materials may allow for an extension of their functionalities to micro- and nanoscale devices, potentially leading to outstanding technological innovations; however, suitable materials and production methods are not yet available. This project seeks to integrate permanent magnet materials with available methods for microchip fabrication to ultimately enable the production of magnetic microscale devices. In order to do so, the formation and post-processing of Fe-Pt alloys will be investigated, with the aim to achieve materials exhibiting high performance even at extremely low size. Target applications will include novel information storage technologies and motion at the microscale for sensors and biomedical chips. Besides these technological aspects, this project will offer undergraduate research internships that will provide students with training and motivation to pursue graduate studies, as well as an opportunity of research management experience for graduate students. In turn, internships of graduate students within companies will enhance their scientific and professional development.