Mechanisms of power module source metal degradation during electro-thermal aging

R. Ruffilli, M. Berkani, P. Dupuy, S. Lefebvre, Y. Weber, M. Legros

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The long-term reliability of power devices for applications in the automotive industry is limited by the electro-thermal and/or thermo-mechanical aging of the metallic parts. In the present work, we characterize the bonding wire and source metallization degradation of power MOSFETs-based devices under accelerated aging conditions, through electron and ion microscopy. The metal degradation is driven by an enhanced self-diffusion of aluminium (Al) atoms along the grain boundaries and a generalized fatigue crack propagation from the surface down to the silicon (Si) bulk. The metallization under the wire bonds is a critical location because it is initially plastically deformed during the bonding process. In addition, the wire-metal interface presents several imperfections, such as small cavities and Al oxide residues. During the electro-thermal cycles, they could be the starting point for harmful cracks that run along the interface (and eventually cause the wire lift-off or the cracking of the substrate). Whichever the propagation direction, the generation of these cracks locally increases the device resistance and temperature, and accelerates the aging process until failure.

Original languageEnglish
Pages (from-to)507-511
Number of pages5
JournalMicroelectronics Reliability
Volume76-77
DOIs
Publication statusPublished - 1 Sep 2017
Externally publishedYes

Fingerprint

Thermal aging
Metals
wire
Wire
degradation
Degradation
Aging of materials
Metallizing
metals
cracks
Cracks
Aluminum
Aluminum Oxide
crack propagation
Silicon
Fatigue crack propagation
Automotive industry
electron microscopy
Microscopic examination
Grain boundaries

Keywords

  • Curvature experiment
  • Failure analysis
  • Focused Ion Beam (FIB)
  • Metallization microstructure aging
  • Power device
  • Scanning Electron Microscopy (SEM)
  • Temperature cycles

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Safety, Risk, Reliability and Quality
  • Surfaces, Coatings and Films
  • Electrical and Electronic Engineering

Cite this

Mechanisms of power module source metal degradation during electro-thermal aging. / Ruffilli, R.; Berkani, M.; Dupuy, P.; Lefebvre, S.; Weber, Y.; Legros, M.

In: Microelectronics Reliability, Vol. 76-77, 01.09.2017, p. 507-511.

Research output: Contribution to journalArticle

Ruffilli, R. ; Berkani, M. ; Dupuy, P. ; Lefebvre, S. ; Weber, Y. ; Legros, M. / Mechanisms of power module source metal degradation during electro-thermal aging. In: Microelectronics Reliability. 2017 ; Vol. 76-77. pp. 507-511.
@article{0f3da4493e8745bab69a9c4007c49f50,
title = "Mechanisms of power module source metal degradation during electro-thermal aging",
abstract = "The long-term reliability of power devices for applications in the automotive industry is limited by the electro-thermal and/or thermo-mechanical aging of the metallic parts. In the present work, we characterize the bonding wire and source metallization degradation of power MOSFETs-based devices under accelerated aging conditions, through electron and ion microscopy. The metal degradation is driven by an enhanced self-diffusion of aluminium (Al) atoms along the grain boundaries and a generalized fatigue crack propagation from the surface down to the silicon (Si) bulk. The metallization under the wire bonds is a critical location because it is initially plastically deformed during the bonding process. In addition, the wire-metal interface presents several imperfections, such as small cavities and Al oxide residues. During the electro-thermal cycles, they could be the starting point for harmful cracks that run along the interface (and eventually cause the wire lift-off or the cracking of the substrate). Whichever the propagation direction, the generation of these cracks locally increases the device resistance and temperature, and accelerates the aging process until failure.",
keywords = "Curvature experiment, Failure analysis, Focused Ion Beam (FIB), Metallization microstructure aging, Power device, Scanning Electron Microscopy (SEM), Temperature cycles",
author = "R. Ruffilli and M. Berkani and P. Dupuy and S. Lefebvre and Y. Weber and M. Legros",
year = "2017",
month = "9",
day = "1",
doi = "10.1016/j.microrel.2017.06.086",
language = "English",
volume = "76-77",
pages = "507--511",
journal = "Microelectronics Reliability",
issn = "0026-2714",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Mechanisms of power module source metal degradation during electro-thermal aging

AU - Ruffilli, R.

AU - Berkani, M.

AU - Dupuy, P.

AU - Lefebvre, S.

AU - Weber, Y.

AU - Legros, M.

PY - 2017/9/1

Y1 - 2017/9/1

N2 - The long-term reliability of power devices for applications in the automotive industry is limited by the electro-thermal and/or thermo-mechanical aging of the metallic parts. In the present work, we characterize the bonding wire and source metallization degradation of power MOSFETs-based devices under accelerated aging conditions, through electron and ion microscopy. The metal degradation is driven by an enhanced self-diffusion of aluminium (Al) atoms along the grain boundaries and a generalized fatigue crack propagation from the surface down to the silicon (Si) bulk. The metallization under the wire bonds is a critical location because it is initially plastically deformed during the bonding process. In addition, the wire-metal interface presents several imperfections, such as small cavities and Al oxide residues. During the electro-thermal cycles, they could be the starting point for harmful cracks that run along the interface (and eventually cause the wire lift-off or the cracking of the substrate). Whichever the propagation direction, the generation of these cracks locally increases the device resistance and temperature, and accelerates the aging process until failure.

AB - The long-term reliability of power devices for applications in the automotive industry is limited by the electro-thermal and/or thermo-mechanical aging of the metallic parts. In the present work, we characterize the bonding wire and source metallization degradation of power MOSFETs-based devices under accelerated aging conditions, through electron and ion microscopy. The metal degradation is driven by an enhanced self-diffusion of aluminium (Al) atoms along the grain boundaries and a generalized fatigue crack propagation from the surface down to the silicon (Si) bulk. The metallization under the wire bonds is a critical location because it is initially plastically deformed during the bonding process. In addition, the wire-metal interface presents several imperfections, such as small cavities and Al oxide residues. During the electro-thermal cycles, they could be the starting point for harmful cracks that run along the interface (and eventually cause the wire lift-off or the cracking of the substrate). Whichever the propagation direction, the generation of these cracks locally increases the device resistance and temperature, and accelerates the aging process until failure.

KW - Curvature experiment

KW - Failure analysis

KW - Focused Ion Beam (FIB)

KW - Metallization microstructure aging

KW - Power device

KW - Scanning Electron Microscopy (SEM)

KW - Temperature cycles

UR - http://www.scopus.com/inward/record.url?scp=85024481537&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024481537&partnerID=8YFLogxK

U2 - 10.1016/j.microrel.2017.06.086

DO - 10.1016/j.microrel.2017.06.086

M3 - Article

VL - 76-77

SP - 507

EP - 511

JO - Microelectronics Reliability

JF - Microelectronics Reliability

SN - 0026-2714

ER -