玻璃碳坩埚蒸镀金膜时物料飞溅的机理分析与控制

Mechanism Analysis and Control of Material Splashing in the Deposition of Gold Film by using Glassy Carbons Crucible

采用玻璃碳坩埚和电子束蒸发设备沉积金膜时,随着黄金物料的消耗,在相同沉积速率下蒸镀所得金膜表面颗粒越来越多,严重影响了薄膜的平整度和局部均匀性。本文用液态金属表面热发射电子引起坩埚壁上球形小液滴电晕放电导致物料飞溅这一理论对该现象进行了解释。在相同的沉积速率下,通过改变坩埚内黄金物料的体积占比获得两种金薄膜,对其表面形貌、红外光谱透射性能等进行了对比分析,验证了理论的正确性。结果表明:当物料体积约占坩埚体积的26%时,金膜表面出现较多黑色颗粒,其形状近似球形或椭球形,主要成分仍为金;当物料体积约占坩埚体积的90%时,金膜表面无黑色颗粒,红外光谱透射率比前者高5%。

When glassy carbons crucible and electron beam evaporation equipment are used for coating,with the consumption of gold material,more particles on the surface of gold film are obtained at the same deposition rate,which seriously affects the flatness and local uniformity of the film.In this work,the phenomenon was explained by the theory that the corona discharge of spherical droplet on the crucible wall caused by thermally electron emission from liquid metal surface led to material splashing.At the same deposition rate,two kinds of gold films were obtained by changing the volume proportion of gold materials in the crucible,and their surface morphology and infrared spectral transmission properties were compared and analyzed.The results showed that when the material volume accounted for about 26%of the crucible volume,there were many black particles on the gold film surface,which were approximately spherical or ellipsoidal in shape,and the main component is still gold.When the material volume accounted for about 26%of the crucible volume,there were no black particles on the gold film surface,and the infrared spectral transmittance is 5%lower than the former.