【作者】 杨波；

【导师】 田修波；

【作者基本信息】 哈尔滨工业大学 ， 材料工程， 2013， 硕士

【摘要】 本文采用磁控溅射技术在不同的基底上沉积铜膜，通过正交试验的方法研究不同的工艺参数对Cu膜组织结构的影响。采用Sn基钎料连接镀铜铝合金、镀铜不锈钢与紫铜，研究不同的沉积工艺对接头剪切强度的影响。溅射电流对铜膜的微观结构及形貌有较大的影响。随着溅射电流的增大，Cu膜晶粒尺寸、表面粗糙度以及沉积速率逐渐增大；基体偏压对Cu膜截面形貌有较大影响，薄膜沉积速率随着基体偏压的增大而减小，偏压为50V时，Cu膜呈现柱状晶生长方式，而偏压增大到100V以上时，柱状晶生长受到抑制；工作气压的大小对薄膜的微观结构影响较小。沉积Cu膜时，Ar气流量及溅射电流对钎焊接头剪切强度有较大影响，Ar气流量较低时，钎焊接头强度较低，拉剪试验时，Cu膜直接从基体上剥离；Ar气流量较高时，溅射电流对接头剪切强度影响最为显著，随着溅射电流的增大，接头的抗剪强度逐渐增大。研究发现，接头强度随着溅射电流的增加而增大的本质原因在于Cu膜厚度的增大。当溅射电流达到1.1A后，继续增大溅射电流到1.3A，接头的剪切强度不再升高，此时接头的强度大小取决于钎料的强度以及钎焊工艺。镀铜铝合金/铜、镀铜不锈钢/铜以及镀铜铝合金/镀铜不锈钢接头强度最高分别可达41.47MPa、43.32MPa和38.74MPa。接头共有3种断裂模式：完全断于钎料层，部分断于钎料层以及完全断于膜基界面处。溅射电流为1.3A时，Cu膜与铝合金基体在膜基界面处发生了冶金反应，EDS及XRD分析显示，界面处产生了CuAl2。随着保温时间的延长，镀铜不锈钢/镀铜铝合金接头强度先增大，后减小，界面Cu6Sn5的厚度逐渐增加，形态由扇贝状变为短棒状，这种变化是由界面化合物层生长以及晶粒粗化过程的扩散造成。更多还原

【Abstract】 Cu films were deposited on different substrates by magnetron sputteringtechnique in this paper. Microstructure of copper films on Si wafer was researchedby orthogonal experiment in which sputtering current, working pressure andsubstrate bias voltage were the main factors. Sn-based solder was used to connectaluminum alloy, stainless steel and copper. Deposition parameters on the shearstrength of the joints were studied.Sputtering current had a significant impact on the copper film microstructureand morphology. Grain size, surface roughness and deposition rate of Cu filmsincreased as the sputtering current increased. Substrate bias voltage had a greatimpact on sectional morphologies of the films. When the bias voltage was50V, Cufilms showed a columnar grain growth mode. While the bias voltage increased to100V, columnar grain was inhibited. The working pressure had a little effect on themicrostructure of Cu films.The shear strength of the soldered joint was weak as Ar gas flow rate was lowduring the film deposition. Cu films were peeled off from the substrate directlyduring the tensile test. While Ar gas flow rate was high, the sputtering current wasthe most significant factor on shear strength of the joint. The joint strengthincreased with the current increased. The results showed that the increasing ofcopper films was the root cause of increasing of the joint strength.When the sputtering current reached1.1A, the shear strength of the jointreached the maximum value，then the joint of the shear strength depended on theproperties of the solder and soldering process.The maximum shear strength of aluminum/copper joints, stainless steel/copper joints and aluminum/stainless steel joints were up to41.47MPa，43.32MPa and38.74MPa. There were three kinds of joint fracture modes:completely broken at the solder layer, partly broken in the solder layer andcompletely broken in interface between film and substrate. The third fracture modeoccurred mainly because the film thickness was thin.When the sputtering current was1.3A, the metallurgical reaction occurred atthe interface of Cu film and the aluminum alloy, EDS and XRD analysis showed that CuAl2generated at the interface.With the increasing of holding time, thickness and shape of Cu6Sn5changed atthe interface of copper coated stainless steel/copper coated aluminum, which wascaused by the growth of the compound layer and grain coarsening caused by thediffusion.更多还原