Degradation Mechanism of Pressure-Assisted Sintered Silver by Thermal Shock Test

Keisuke Wakamoto, Takukazu Otsuka, Ken Nakahara and Takahiro Namazu
Additional contact information
Keisuke Wakamoto: ROHM Co., Ltd., Kyoto 615-8585, Japan
Takukazu Otsuka: ROHM Co., Ltd., Kyoto 615-8585, Japan
Ken Nakahara: ROHM Co., Ltd., Kyoto 615-8585, Japan
Takahiro Namazu: Faculty of Engineering, Uzumasa, Kyoto University of Advanced Science, Kyoto 615-8577, Japan

Energies, 2021, vol. 14, issue 17, 1-15

Abstract: This paper investigates the degradation mechanism of pressure-sintered silver (s-Ag) film for silicon carbide (SiC) chip assembly with a 2-millimeter-thick copper substrate by means of thermal shock test (TST). Two different types of silver paste, nano-sized silver paste (NP) and nano-micron-sized paste (NMP), were used to sinter the silver film at 300 °C under a pressure of 60 MPa. The mean porosity ( p ) of the NP and MNP s-Ag films was 2.4% and 8%, respectively. The pore shape of the NP s-Ag was almost spherical, whereas the NMP s-Ag had an irregular shape resembling a peanut shell. After performing the TST at temperatures ranging from −40 to 150 °C, the scanning acoustic tomography (SAT) results suggested that delamination occurs from the edge of the assembly, and the delamination of the NMP s-Ag assembly was faster than that of the NM s-Ag assembly. The NMP s-Ag assembly showed a random delamination, indicating that the delamination speed varies from place to place. The difference in fracture mechanism is discussed based on cross-sectional scanning electron microscope (SEM) observation results after TST and plastic strain distribution results estimated by finite element analysis (FEA) considering pore configuration.

Keywords: sintered silver; porosity; thermal mechanical reliability design; fracture mechanism; low thermal impedance packaging (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2021
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/14/17/5532/pdf (application/pdf)
https://www.mdpi.com/1996-1073/14/17/5532/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:14:y:2021:i:17:p:5532-:d:629132

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().