Fabrication of Bismuth Thin Films Nano-Hall Sensors for Room Temperature Scanning Micro-Hall Probe Microscope Imaging of Ferromagnetic Microstructures

对于信息技术的发展，如超高密度磁记录介质、高矫顽力永磁体和用于制造新型自旋电子器件的多层铁磁结构，基本了解外磁场中磁畴的行为是非常重要的。我们研制了一台室温扫描霍尔探针显微镜(RT-SHPM)，用于在3T Oe的脉冲磁场作用下，对铁磁微结构表面的局域杂散场进行非侵入性的定量成像。然而，磁记录介质的进步导致了对提高SHPM空间分辨率的日益增长的需求，由于表面耗尽效应，使用半导体GaAsAlGaAs微霍尔传感器的SHPM的空间分辨率被限制在1.0x1.0μm。使用Bimut(Bi)(一种半金属，表现出大的霍尔系数和可以忽略的表面耗尽)来制造亚微米霍尔传感器sh…更多的OWS有望成为提高RT-SHPM技术空间分辨率的一种手段。传统的MFM系统具有~100 nm的空间分辨率，这是空间分辨率研究的基准和目标。在本研究中，我们成功地利用热蒸发法制备了50 nm×50 nm霍尔传感器。沉积后真空退火改善了薄膜的电学性能。纳米霍尔传感器被成功地应用于结晶石榴石薄膜表面的磁成像。本报告描述了2003至2004年间作为科学研究资助计划(C)(2)的一部分，开展了为期两年的用于铁磁性微结构成像的铋薄膜纳米霍尔传感器的制备研究。介绍了铋纳米霍尔传感器的制备方法和电学特性。此外，还展示了该双纳米传感器在石榴石薄膜成像中的应用。较少

A fundamental understanding of the behavior of magnetic domains in external magnetic fields is important for the development of information technology such as ultra-high density magnetic recording media, high coercivity permanent magnets and multilayered ferromagnetic structures used for fabricating novel ‘spintronic'' devices. We have developed a room temperature scanning Hall probe microscopy (RT-SHPM) for the non-invasive and quantitative imaging of localized stray fields at the surfaces of ferromagnetic magnetic microstructures in the presence of pulsed external magnetic fields of 3 T Oe. However, advances in magnetic recording media have led to increasing demands for improvements in the spatial resolution of SHPM which using semiconducting GaAs/AlGaAs micro-Hall sensors is limited to 1.0 x 1.0μm due to surface depletion effects.The use of bismuth (Bi)(a semimetal, which exhibits a large Hall coefficient and negligible surface depletion) for fabrication of submicron Hall sensors sh … More ows promise as a means of improving the spatial resolution of RT-SHPM technology. Conventional MFM systems have a spatial resolution of 〜100nm, a figure which serves as a benchmark and target for studies on spatial resolution.In this research we succeeded in fabricating 50nm x 50nm Hall sensors using Bi thin films deposited by thermal evaporation. The electrical properties of the films were improved by post-deposition annealing in vacuum. The nano-Hall sensors were successfully used for magnetic imaging the surface of crystalline garnet thin films.This report describes the research carried out on "Fabrication of Bismuth Thin Films Nano-Hall Sensors for Room Temperature Scanning Micro-Hall Probe Microscope Imaging of Ferromagnetic Microstructures" as part of the Grant-in-Aid for Scientific Research (c)(2)for two years between 2003 and 2004. The fabrication and electrical characteristics of the Bi nano-Hall sensors are described. Also, the use of the Bi-nanosensors for imaging garnet thin films is demonstrated. Less