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

N1 - Publisher Copyright: © 2024 The Authors

PY - 2024/4/7

Y1 - 2024/4/7

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

UR - https://pureadmin.unileoben.ac.at/portal/en/publications/microscopic-fracture-toughness-of-notched-porous-sintered-cu-microcantilevers-for-power-electronics-packaging(bcd58520-adbe-42e4-9faa-647d7b4f9b8e).html

U2 - 10.1016/j.msea.2024.146316

DO - 10.1016/j.msea.2024.146316

M3 - Article

AN - SCOPUS:85187232796

VL - 897.2024

JO - Materials Science and Engineering: A

JF - Materials Science and Engineering: A

SN - 0921-5093

IS - April

M1 - 146316

ER -