Song, HG Ahn, JP Morris, JW 2024-01-21T12:01:37Z 2024-01-21T12:01:37Z 2021-09-01 2001-09 0361-5235 https://pubs.kist.re.kr/handle/201004/140231 In this work we studied the initial microstructure and microstructural evolution of eutectic Au-Sn solder bumps on Cu/electroless Ni/Au. The solder bumps were 150-160 mum in diameter and 45-50 mum tall, reflowed on Cu/electroless Ni/Au, and then aged at 200 degreesC for up to 365 days. In addition, Au-Ni-Sn-alloys were made and analyzed to help identify the phases that appear at the interface during aging. The detailed interfacial microstructure was observed using a transmission electron microscope (TEM). The results show that the introduction of Au from the substrate produces large islands of zeta -phase in the bulk microstructure during reflow. Two Au-Ni-Sn compounds are formed at the solder/substrate interface and grow slowly during aging. The maximum solubility of Ni in the phase was measured to be about 1 at.% at 200 degreesC, while Ni in the delta -phase is more than 20 at.%. The electroless Ni layer is made of several sublayers with slightly different compositions and microstructures. There is, in addition, an amorphous interaction layer at the solder/electroless Ni interface. English SPRINGER ELECTROLESS NI-P SOLID-STATE AMORPHIZATION NICKEL/SOLDER INTERFACE THERMAL-STABILITY CRYSTALLIZATION PART The microstructure of eutectic Au-Sn solder bumps on Cu/electroless Ni/Au Article 10.1007/s11664-001-0133-9 1 JOURNAL OF ELECTRONIC MATERIALS, v.30, no.9, pp.1083 - 1087 JOURNAL OF ELECTRONIC MATERIALS 30 9 1083 1087 scie scopus 000171089800006 Engineering, Electrical & Electronic Materials Science, Multidisciplinary Physics, Applied Engineering Materials Science Physics Article; Proceedings Paper ELECTROLESS NI-P SOLID-STATE AMORPHIZATION NICKEL/SOLDER INTERFACE THERMAL-STABILITY CRYSTALLIZATION PART Au-Sn solder electroless Ni/Au metallization Au-Ni-Sn compounds