GeC薄膜的射频磁控反应溅射制备及性质

用射频磁控反应溅射法在ZnS衬底上制备了GeC薄膜，研究了工艺参数对Ge靶溅射及GeC薄膜红外透射性能的影响.衬底温度较低时GeC薄膜中含有H，形成了CH₂,CH₃,Ge-CH₃等，使薄膜产生红外吸收；随衬底温度升高，薄膜红外吸收明显减小.靶基距、射频功率、Ar:CH₄气体流量比、总气压对靶面中毒及溅射影响较大，但对GeC薄膜红外吸收影响较小.靶面中毒严重时，所制备无氢GeC薄膜附着性能差，随靶中毒减弱薄膜附着性能变好.优化工艺后，在ZnS衬底上制备了附着性能良好的无氢GeC薄膜，其折射率约为1.78，薄膜中C的含量比Ge的大，二者主要形成了C—Ge键.所制备的GeC/GaP红外增透保护膜系对ZnS衬底有良好的增透效果. 关键词： GeC薄膜 红外透射光谱 射频磁控溅射 XPS

Preparation and properties of GeC thin films deposited by reactive RF magnetron sputtering

GeC thin films were deposited on ZnS substrates with reactive RF magnetron sputtering, and the influences of the processing parameters on sputtering of the Ge target and IR transmission properties of the GeC films were studied. At low substrate temperatures, the GeC film contained H atoms in forms of CH₂，CH₃ and Ge-CH₃ groups, which caused IR absorption, whereas the absorption decreased obviously at elevated substrate temperatures. Target-substrate distance, RF power, Ar:CH₄ gas flow ratio and total gas pressure had great impacts on the poisoning and sputtering of the Ge target, but their impacts on the IR absorption of the GeC film was small. When the Ge target was poisoned greatly, adhesion of the GeC film was inferior, with the weakening of the target poisoning, adhesion of the GeC film increased. Hydrogen-free GeC film with excellent adhesion was prepared on ZnS substrate under optimized parameters, and its refractive index was about 1.78. The C content in the GeC film was larger than the Ge content, and C and Ge formed mainly C—Ge bonds. GeC/GaP antireflective and protective film system was prepared on ZnS substrate, giving good antireflective effect.