Pt-10Ir超细键合丝退火过程中组织与性能的演化规律研究

Evolution Laws of Microstructure and Properties of Pt-10Ir Ultrafine Bonding Wire During Annealing

铂铱键合丝是一种应用于特种微电子器件封装的高强度引线键合材料,经拉拔制备的铂铱合金微细丝材的热处理是调控键合丝终服役性能的关键环节。以Φ25μm超细Pt-10Ir键合丝为研究对象,通过高分辨FIB-EBSD联动表征技术,对不同退火工艺下超细丝材显微组织及形变织构进行了深入分析,并对其力/电学性能的演变进行了探究。结果表明:随着退火温度的升高,显微组织由拉拔态的细小纤维状晶粒逐渐转变为部分等轴组织,等轴状组织优先在晶界处形核长大且丝材织构强度逐渐下降,破断力逐渐降低,延伸率逐渐升高而电阻率则呈现出先降低后升高的趋势。Pt-10Ir超细键合丝在600℃×30 min退火后,主要发生回复,未发生明显的再结晶,织构取向演变为<111>平行于丝材拉拔方向的形变织构,破断力为37.06 cN,抗拉强度为755.29 MPa,延伸率为1.30%,电阻率为22.81μΩ·cm,表现出好的力/电综合性能。该研究可为贵金属超细键合丝材的性能优化提供理论和实验基础。

Platinum iridium bonding wire is a high-strength wire bonding material used in the packaging of special microelectronic devices,and heat treatment is the key method for the cold-deformed platinum-iridium alloy microfilament to control the lifetime service performance of the bonding wire.Based on theΦ25μm Pt-10Ir ultrafine bonding wire,the microstructure and deformation of ultrafine filaments under different annealing processes were analyzed and measured by high-resolution FIB-EBSD linkage characterization technology,and the evolution of mechanical and electrical properties was studied.The results show that with the increase in annealing temperature,the microstructure gradually changes from fine fibrous grains to partially equiaxed grains.The equiaxed grains preferentially grow at the grain boundary.Simultaneously,the intensity of the silk texture gradually decreases,the breaking force gradually decreases,the elongation gradually increases,and the resistivity shows a trend of decreasing first and then increasing.After the annealing of Pt-10Ir ultra-fine bonding wire at 600℃for 30 min,recovery rather than recrystallization occurs in the microstructure,the texture orientation evolves into a deformation texture parallel to the wire drawing direction of<111>with a breaking force of 37.06 cN,a tensile strength of 755.29 MPa,an elongation of 1.30%,and a resistivity of 22.81μΩ·cm,showing excellent mechanical/electricity comprehensive performance.