TY - JOUR
T1 - Microscopic fracture toughness of notched porous sintered Cu micro-cantilevers for power electronics packaging
AU - Hu, Dong
AU - Du, Leiming
AU - Alfreider, Markus
AU - Fan, Jiajie
AU - Kiener, Daniel
AU - Zhang, Guoqi
PY - 2024
Y1 - 2024
N2 - To fulfill the high-temperature application requirement of high-power electronics packaging, Cu nanoparticle sintering technology, with benefits in low-temperature processing and high-melting point, has attracted considerable attention as a promising candidate for the die-attach interconnect. Comprehensive mechanical characterization of the sintered layer at a microscale is necessary to deepen the understanding of the fracture behavior and improve the reliable design of materials. In this study, microscale cantilevers with different notch depths were fabricated in a 20 MPa sintered interconnect layer. Continuous dynamical fracture testing of the microcantilevers was conducted in situ in a scanning electron microscope to detail the failure characteristic of the porous sintered structure. The microscopic fracture toughness of different notched specimens was obtained from the J-integral in the frame of elastic-plastic fracture mechanics. Specimens with deeper notches presented higher resistance to crack extension, while geometry factors of notch-to-width ratio between 0.20 and 0.37 exhibited a relatively stable microscopic fracture toughness ranging from 3.2 ± 0.3 to 3.6 ± 0.1 MPa m1/2.
AB - To fulfill the high-temperature application requirement of high-power electronics packaging, Cu nanoparticle sintering technology, with benefits in low-temperature processing and high-melting point, has attracted considerable attention as a promising candidate for the die-attach interconnect. Comprehensive mechanical characterization of the sintered layer at a microscale is necessary to deepen the understanding of the fracture behavior and improve the reliable design of materials. In this study, microscale cantilevers with different notch depths were fabricated in a 20 MPa sintered interconnect layer. Continuous dynamical fracture testing of the microcantilevers was conducted in situ in a scanning electron microscope to detail the failure characteristic of the porous sintered structure. The microscopic fracture toughness of different notched specimens was obtained from the J-integral in the frame of elastic-plastic fracture mechanics. Specimens with deeper notches presented higher resistance to crack extension, while geometry factors of notch-to-width ratio between 0.20 and 0.37 exhibited a relatively stable microscopic fracture toughness ranging from 3.2 ± 0.3 to 3.6 ± 0.1 MPa m1/2.
KW - Continuous stiffness testing
KW - Cu nanoparticles sintering
KW - Elastic-plastic fracture mechanics
KW - Microscopic fracture toughness
UR - http://www.scopus.com/inward/record.url?scp=85187232796&partnerID=8YFLogxK
U2 - 10.1016/j.msea.2024.146316
DO - 10.1016/j.msea.2024.146316
M3 - Article
AN - SCOPUS:85187232796
SN - 0921-5093
VL - 897
JO - Materials Science and Engineering: A
JF - Materials Science and Engineering: A
M1 - 146316
ER -