采用电子束反应蒸发生长Zn0.66Co0.34O薄膜,生长温度仅为250℃,尔后在Ar气氛中500℃退火1h.场发射扫描电镜测量显示薄膜由粒径约10~20nm的晶粒所构成.X射线衍射测量表明薄膜在退火前后均呈类ZnO的六方纤锌矿结构.振动样品磁场计测量室温下薄膜的M-H曲线,结果显示退火前薄膜呈超顺磁性,退火后则为铁磁、超顺磁混合态,这表明退火提供了足够能量使得薄膜中一部分磁性Zn0.66Co0.34O小晶粒融合成大晶粒,新晶粒的尺寸超过了Zn0.66Co0.34O材料的超顺磁临界半径而表现出铁磁性,但由于另有部分晶粒仍表现为超顺磁性,故薄膜呈铁磁性与超顺磁性的混合态.
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