钴掺杂锗基稀磁半导体的制备

Synthesis of Ge-based Diluted Magnetic Semiconductors Doped with Co

采用溶胶-凝胶法制备出钴掺杂的锗基稀磁半导体。利用场发射扫描电子显微镜(SEM),X射线衍射仪(XRD)、拉曼光谱仪和多功能物相测试系统(PPMS)对产物进行表征。结果表明,钴掺杂物的添加并没有影响试样的表面形貌。当m(乙酸钴)/m(二氧化锗)<0.010 0,试样具有单一立方锗晶体结构;而m(乙酸钴)/m(二氧化锗)=0.025 0的试样中存在着CoGe第二相化合物。拉曼测试表明,钴原子已经掺杂进入锗晶格中。室温条件下的磁滞回线表明,m(乙酸钴)/m(二氧化锗)=0.010 0的样品具有室温铁磁性。

Co doped Ge based diluted magnetic semiconductor materials were fabricated by using a sol-gel method. The morphologies, phase structure, and the magnetic property of the samples were characterized by field-emission scanning electron microscopy （SEM）, X-ray diffraction （XRD）, Raman spectroscopy and a multi-phase physical measurement system （PPMS）. The addition of cobalt dopant does not affect the surface morphology of the samples. Samples that m（cobaltous acetate）/m（germanium dioxide） is less than 0. 010 0 have a single cubic crystal Ge phase. Some CoGe secondary phases have been formed in the 0. 025 0 Co-doped sample. Raman analyses disclose that cobalt atoms have been incorporated into Ge matrix. The hysteresis loop measured at room temperature shows that the 0. 010 0 sample is ferromagnetic.