借助纳米压痕试验方法，对Cu/SAC305/Cu，Cu/SAC0705/Cu和Cu/SAC0705BiNi/Cu微焊点体钎料在不同最大载荷下的压入蠕变性能进行比较，并分析和讨论Bi、Ni元素的添加对低银Cu/SAC0705/Cu微焊点体钎料蠕变性能的影响。试验采用一次加载-卸载方式，加载时最大载荷分别为20 mN、30 mN、40 mN和50 mN，保载时间均为180 s。采用FEI SIRION扫描电子显微镜对微焊点体钎料在不同最大载荷下的压痕形貌进行观察。结果表明：在相同最大载荷和保载时间条件下，3种微焊点中Cu/SAC0705BiNi/Cu的蠕变深度和压痕尺寸均小于Cu/SAC305/Cu和Cu/SAC0705/Cu。在4种不同最大载荷下，与Cu/SAC0705/Cu微焊点体钎料相比，Cu/SAC0705BiNi/Cu微焊点体钎料的压入蠕变率分别降低了11.883%、16.059%、 8.815 7%和12.891%。Bi、Ni元素的添加，使Cu/SAC0705/Cu微焊点体钎料的蠕变应力指数提高了32.175%，有效提高了低银Cu/SAC0705/Cu微焊点体钎料的抗蠕变性能。

The indentation creep behavior of the bulks of Cu/SAC305/Cu,Cu/SAC0705/Cu and Cu/SAC0705BiNi/Cu lead-free micro solder joints are comparatively investigated at different maximum load by nanoindentation method. And the Bi,Ni concentration on the creep behavior of the bulks of Cu/SAC0705/Cu micro solder joints are analyzed and discussed. The mode of loading-unloading is adopted. Here the holding time is 180 s and the maximum load is 20 mN,30 mN,40 mN,and 50 mN,respectively. The indentation morphologies of the bulks of the micro solder joints at different maximum load are observed by FEI SIRION scanning electron microscopy (SEM). The results indicate that the creep depth and indentation size of the bulks of Cu/SAC0705BiNi/Cu are smaller than that of Cu/SAC305/Cu and Cu/SAC0705/Cu at the same maximum load and holding time. Compared with the bulks of Cu/SAC0705/Cu micro solder joints,at four different maximum loads,the indentation creep rate (C_IT) of the bulks of Cu/SAC0705BiNi/Cu micro solder joints are declined 11.883%,16.059%,8.815 7%,and 12.891%,respectively. The creep stress exponent of the bulks of Cu/SAC0705/Cu micro solder joints increases 32.175 % by adding Bi and Ni elements. The addition of Bi and Ni elements can effectively improve the creep resistance of the bulks of low-Ag Cu/SAC0705/Cu micro solder joints.