CVD金刚石衬底上抗氧化、增透膜的制备与性能

PREPARATION AND PROPERTIES OF ANTIOXIDATIVE AND ANTIREFLECTIVE FILMS ON CVD DIAMOND

采用射频磁控反应溅射法在化学气相沉积(chemical vapor deposition,CVD)的金刚石衬底上制备了AlN薄膜以及AlN/Si和AlN/Ge膜。通过X射线衍射分析了衬底加热温度对薄膜微结构的影响和薄膜高温下的氧化行为。结果表明:在衬底加热温度低于380℃时制备的AlN薄膜为非晶态,480℃时AlN薄膜为六方多晶。AlN薄膜在800℃热暴露后开始氧化,900℃时基本被氧化为Al2O3。在CVD金刚石上制备的AlN/Si和AlN/Ge膜都能提高金刚石在长波红外波段(8～10μm)的透过性能,单面最大增透分别为8%和3%。镀有AlN/Ge膜的CVD金刚石在800℃高温热暴露实验中,有AlN/Ge膜保护的金刚石表面未发生刻蚀。高温下AlN/Ge膜对金刚石有很好的保护作用,同时增透效果没有明显下降。

Aluminum nitride（AlN）,AlN/Si and AlN/Ge thin films were prepared on the chemical vapor deposition（CVD） diamond substrates by radio-frequency magnetron reactive sputtering.The influences of substrate heated temperature on the structures of AlN films and the oxidation behavior of CVD diamond coated with AlN films ware investigated by X-ray diffraction.The results show that AlN film deposited on CVD diamond is amorphous when the temperature of CVD diamond is less than 380 ℃,and AlN film is hexagonal polycrystals when the temperature of CVD diamond is 480 ℃.After heat exposure at 800 ℃,AlN film begins to oxidize,and is completely oxidized at 900 ℃.AlN/Si and AlN/Ge films prepared on CVD diamond have both antioxidation and antireflection characteristics,and it is found that the transmittance of CVD diamonds coated with single-side AlN/Si and AlN/Ge films increases by 8% and 3% in the long wave infrared light（8-12 μm）,respectively.After CVD diamond coated with AlN/Ge film was exposured at 800 ℃,under the protection of the AlN/Ge film,the surface of CVD diamond can not be etched.Under high temperature the AlN/Ge film can be protect the CVD diamond against from etching,and the effect of anti-reflection is not reduced remarkably.