Fe/Sn共掺杂In_2O_3稀磁半导体薄膜的磁性和输运性质

Magnetic and transport properties of Fe/Sn codoped In_2O_3 diluted magnetic semiconductor films

采用脉冲激光沉积方法在Al_2O_3衬底上制备了Fe/Sn共掺杂的(In_(0.93)Fe_(0.05)Sn_(0.02))_2O_3薄膜,研究了沉积过程的氧气分压对薄膜结构、磁性和输运性质的影响,以揭示其铁磁性来源和机制。(In_(0.93)Fe_(0.05)Sn_(0.02))_2O_3薄膜为单相立方In2O3结构,Fe和Sn取代了In2O3中In的位置。在不同氧气分压下制备的(In_(0.93)Fe_(0.05)Sn_(0.02))_2O_3薄膜具有明显的室温铁磁性,随着氧气分压的增加,薄膜的铁磁性减小。输运测量表明,(In_(0.93)Fe_(0.05)Sn_(0.02))_2O_3薄膜为n型半导体,载流子浓度约为1020 cm-3,在低温时具有明显的磁电阻效应。研究结果表明(In_(0.93)Fe_(0.05)Sn_(0.02))_2O_3薄膜的铁磁性是本征的,载流子浓度对薄膜的铁磁性有重要影响。

The（In0.93Fe0.05Sn0.02）2O3films were deposited on Al2O3（0001）substrates by pulsed laser deposition technique.In order to reveal the origin and mechanism of its ferromagnetism,the effect of oxygen partial pressure on the structural,magnetic and transport properties of the films has been investigated.The films have a structure of cubic bixbyite In2O3and In has been replaced by Fe and Sn.The（In0.93Fe0.05Sn0.02）2O3 films exhibit the robust ferromagnetic behavior at room temperature and the magnetization is decreased with the increase of oxygen pressure.The films are n-type semiconductor with the carrier concentration of 1020 cm-3.The carrier densities are important for the ferromagnetism of the films.The negative magnetoresistance at lower temperatures is observed in the films,indicating the ferromagnetism is intrinsic in（In0.93Fe0.05Sn0.02）2O3films.