工艺因素对离子束增强沉积氮化硅薄膜组成与结构的影响

Effect of Processing Variables on the Composition and Microstructure of lon Beam Enhanced Deposition SisN4 Film

本世纪８０年代以来，利用各种表面技术将陶瓷材料涂覆于金属零件表面的研究发展很快，离子束增强沉积技术以其突出的优点更受到重视．利用这种技术合成陶瓷薄膜是一种新的物理气相沉积方法，而沉积薄膜的质量、性能和成膜速度都会受到工艺因素的影响．由于氮化硅陶瓷的硬度高，韧性和高温稳定性都比较好，是一种相当理想的耐磨材料，且其还有一定的自润滑性．因此，着重研究了氮离子束流和束压、氮离子与硅原子在基片上的到达比，以及不同基体对离子束增强沉积氮化硅薄膜的化学组成和晶体结构的影响．结果表明，薄膜中Ｎ／Ｓｉ原子比是随着离子原子到达比的增大而增大，要使氮与硅的原子比达到Ｓｉ３Ｎ４中的化学计量比１．３３，到达比就必须达到４；将氮离子束压由３ｋＶ增大到９ｋＶ，可以使薄膜中的氮含量明显提高，但继续增大束压，氮原子含量却反而逐渐降低；沉积在单晶硅基片上的Ｓｉ３Ｎ是非晶态，而沉积于５２１００钢片上的则是β－Ｓｉ３Ｎ４多晶体。研究结果可以作为优化制膜工艺的科学依据。

In the last decade,the researches of the ceramic films coated on the surface of metallic parts by various surface techniques have been developed rapidly,More attentions were paid on theion beam enhanced deposition( IBED)technique due to its obvious advantages. The quality,performance and deposition rate of the deposited films by this new PVD method were related closelywith the processing variables. Silicon nitride is an ideal wear-resistant material by its high hardness,good toughness and stability at high temperature. It shows a certain self-lubrication property aswell. In this paper,the effects of beam current and voltage of nitrogen ions,the arriving ratio ofnitrogen ions to silicon atoms on substrate and different subetrates on the compositions andmicrostructure of IBED Si3N4 were investigated. The results showed that the atom ratio of N/Siin the film was increased with the increasement of arriving ratio of nitrogen ions to silicon atoms Thestoichiometric ratio of 1.3 3 in the Si3N4 film could be obtained only when the arriving ratio reached4.The nitrogen content in the film in creased obviously with the increasement of nitrogen ionvoltage from 3kV to 9kV. But it went down when the voltage was over 9kV(such as from 9kV to15kV).The Si3N4 film deposited on the single crystal silicon wafer was amorphous,whereas thefilm on the 52100 steel was β-Si3N4 crystal.