Abstract Iron pyrite (FeS2) incorporated with cobalt dopant varying from 2% to 6% atomic ratio, was synthesized by using an aqueous hydrothermal process. The thin films of Co-doped FeS2 were fabricated by a vacuum thermal evaporation of synthesized FeS2 powder. The structural, electrical and optical properties of as-deposited and sulfurized films were investigated. The X-ray diffraction results indicated that the synthesized powder and thin films showed a cubic pyrite structure. The crystallinity of FeS2 was slightly degraded by the doping of cobalt. The dependence of thin-film resistance on the temperature indicated an increase of activation energy until 3 at% cobalt doping and then decreased the resistance with the increase of cobalt concentration. Hall effect measurements showed that the Co-doped samples have n-type conduction except for the 2 at%. The carrier concentration was in the order of 1018 cm−3, whereas, the carrier mobility decreased from 6.52 cm2/V.s to 4.3 cm2/V.s with the increase of cobalt dopant. The photosensitivity of undoped and cobalt-doped FeS2 films was measured under AM 1.5G and NIR light. The sulfurized films showed a higher photoresponse than the as-deposited films for both visible and IR lights.

中文翻译：

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钴掺杂黄铁矿 (FeS2) 薄膜的制备与表征

摘要 黄铁矿 (FeS2) 与钴掺杂剂的原子比从 2% 到 6% 不等，是通过使用水热法合成的。通过真空热蒸发合成的 FeS2 粉末制备 Co 掺杂的 FeS2 薄膜。研究了沉积和硫化薄膜的结构、电学和光学性能。X射线衍射结果表明合成的粉末和薄膜显示出立方黄铁矿结构。FeS2 的结晶度因钴的掺杂而略微降低。薄膜电阻对温度的依赖性表明活化能增加直到 3 at% 钴掺杂，然后随着钴浓度的增加电阻降低。霍尔效应测量表明，除了 2 at% 之外，Co 掺杂样品具有 n 型传导。载流子浓度约为 1018 cm-3，而随着钴掺杂剂的增加，载流子迁移率从 6.52 cm2/Vs 下降到 4.3 cm2/Vs。在 AM 1.5G 和 NIR 光下测量未掺杂和钴掺杂的 FeS2 薄膜的光敏性。对于可见光和红外光，硫化膜显示出比沉积膜更高的光响应。