室温透明磁性半导体及相关器件

项目名称： 室温透明磁性半导体及相关器件

项目编号： No.51471093

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 章晓中

作者单位： 清华大学

项目金额： 85万元

中文摘要： 目前的稀磁半导体大都是在半导体材料里掺入少量铁磁元素，但是这种稀磁半导体的居里温度不高，无法满足电子自旋器件的工作要求。和稀磁半导体研究思路相反， 我们在磁性金属里添加氧元素， 把该磁性金属转变为非晶态的室温透明铁磁半导体CoFeTaBO薄膜，该材料的居里温度大于350 K，禁带宽度为3.6eV，载流子浓度为10E21cm-3，该材料有显著的反常霍尔效应，在低温下有奇异的磁阻现象，还有极大的法拉第效应。该方法为研究室温磁性半导体开辟了新路。本申请的主要研究内容是：（1）改进材料制备工艺，提高该新型室温磁性半导体的物性；（2）研究如何采用离子液体双电层结构来制备场效应器件，以实现在室温下用电场来调控磁性；（3） 用该磁性半导体和Si构成的异质结做非偏振光的自旋注入研究；（4）研究我们的室温磁性半导体中电磁光的相互作用和耦合以及如何利用它们构建新的器件。

中文关键词： 磁性薄膜；磁性半导体；稀磁半导体；自旋电子学

英文摘要： Diluted semiconductor can be realized by doping a small amount of ferromagnetic element into semiconductor. However, such diluted semiconductors have a Curie temperature less than 200K so that they cannot be used as spintronic device at room temperature. By using opposite way of realizing diluted semiconductor, we introduced oxygen into CoFeTaB ferromagnetic metal glass and converted the metal glass to transparent room temperature ferromagnetic semiconductor CoFeTaBO thin film. This ferromagnetic semiconductor has a Curie temperature over 350K, optical band gap of 3.6eV and carrier density of 10E21cm-3. The material shows an abnormal Hall Effect and it has an interesting magnetoresistance effect at low temperature. The material also shows a giant Faraday Effect. This new method opens a new way to realize room temperature ferromagnetic semiconductor. The research contents of this application are: (1) enhance the physical properties of our new room temperature ferromagnetic semiconductor by improving fabrication method; (2) make a field effect device by using ion liquid double electric layers for studying modulation of magnetism by electric field at room temperature; (3) make a ferromagnetic semiconductor/Si heterojunction for studying spin injection by non-polarized light; (4) study interaction and coupling among electric, magnetic and optic properties of this ferromagnetic semiconductor for new spintronic device.

英文关键词： magnetic film;magnetic semiconductor;diluted magnetic semiconductor;spintronics