离子源辅助电子枪蒸发制备Ge_(1-x)C_x薄膜

Preparation of Ge_(1-x)C_x Thin Film by e-gun Evaporation Assisted with Ion Source

应用电子枪蒸发纯Ge,考夫曼离子源辅助的方法在Ge基底上沉积了Ge1-xCx薄膜.制备过程中,Ge作为蒸发材料,CH4作为反应气体.通过改变CH4/（CH4＋Ar）的气体流量比（G）,制备了G从40%到85%的Ge1-xCx薄膜.应用X射线衍射仪（XRD）测量了Ge1-xCx薄膜的晶体结构,使用傅里叶红外光谱仪（FTIR）测量了2～22 μm的光学透过率,X射线光电子能谱测试（XPS）计算得到C的含量随G的变化关系,用纳米压痕硬度测试计测量了Ge1-xCx薄膜的硬度,原子力显微镜（AFM）测量了G为60%,85%时Ge1-xCx薄膜的表面粗糙度.测试结果表明：制备的Ge1-xCx薄膜在不同的G值下均为无定形结构.折射率随着G值的增加而减小,在3.14～3.89之间可变,并具有良好的均匀性以及极高的硬度.

Ge1-xCx thin film was deposited on Ge substrate by e-gun evaporation and Kaufman ion source assisted technique.During the deposition process,Ge was evaporated by e-gun and CH4 was ionized by Kaufman ion source as a reactive gas.The CH4/（CH4＋Ar） flow rate ratio （G） was carefully controlled to obtain different C concentration and it was measured through X-ray Photoelectron Spectroscopy （XPS）. Crystal structure was investigated by X-ray Diffraction （XRD）.The optical transmittance of Ge1-xCx thin film in the infrared region between 2～22 μm was characterized by Fourier Transform Infrared Spectroscopy （FTIR） and the uniformity of Ge1-xCx thin film was analyzed using Atomic Force Microscopy （AFM）.Hardness of Ge1-xCx thin film was measured via nano-indentation.Test results indicated the fabricated Ge1-xCx thin films had finely tunable refractive index between 3.14～3.89,good uniformity and high hardness.This shows that e-gun evaporated pure Ge and Kaufman ion source assisted technique is a promising technique to fabricate Ge1-xCx thin film.