Geometrical enhancement of low-field magnetoresistance in silicon
Geometrical enhancement of low-field magnetoresistance in silicon
复制标题
硅中低场磁阻的几何增强
DOI：
10.1038/nature10375
复制
发表时间：
2011-09-15
期刊：
影响因子：
64.8
通讯作者：
Tan, Xinyu
中科院分区：
文献类型：
--
作者：
Wan, Caihua;Zhang, Xiaozhong;Tan, Xinyu
在一些非磁性半导体，不同的理论暗示，，在这里，我们表明，在轻掺杂硅IMR可以显着增强通过空穴注入，然后通过施加的电流在低磁场下出现调谐。在我们的器件中，“不均匀性”是由导电分别由少数和多数电荷载流子（空穴和电子）主导的区域之间形成的p-n边界提供的;施加磁场会扭曲边界区域中的电流，导致大的磁阻。由于这是一种本质上的空间效应，因此可以利用器件的几何形状来进一步增强IMR：我们设计了一种IMR器件，其低场室温场灵敏度大大提高，磁电阻在0.07 T时达到10%，在0.2 T时达到100%，接近商业巨磁电阻器件的性能。对低磁场的高灵敏度和大的高场响应的组合应该使该器件概念对磁场传感行业具有吸引力。此外，由于我们的设备是基于传统的硅平台，它应该可以将其与现有的硅设备集成，从而有助于硅基磁电子学的发展。
Inhomogeneity-induced magnetoresistance (IMR) reported in some non-magnetic semiconductors,,,,,,,, particularly silicon,,,, has generated considerable interest owing to the large magnitude of the effect and its linear field dependence (albeit at high magnetic fields). Various theories implicate,,,,,,,,,spatial variation of the carrier mobility as being responsible for IMR. Here we show that IMR in lightly doped silicon can be significantly enhanced through hole injection, and then tuned by an applied current to arise at low magnetic fields. In our devices, the ‘inhomogeneity’ is provided by the p–n boundary formed between regions where conduction is dominated by the minority and majority charge carriers (holes and electrons) respectively; application of a magnetic field distorts the current in the boundary region, resulting in large magnetoresistance. Because this is an intrinsically spatial effect, the geometry of the device can be used to enhance IMR further: we designed an IMR device whose room-temperature field sensitivity at low fields was greatly improved, with magnetoresistance reaching 10% at 0.07 T and 100% at 0.2 T, approaching the performance of commercial giant-magnetoresistance devices,. The combination of high sensitivity to low magnetic fields and large high-field response should make this device concept attractive to the magnetic-field sensing industry. Moreover, because our device is based on a conventional silicon platform, it should be possible to integrate it with existing silicon devices and so aid the development of silicon-based magnetoelectronics.