Suppression and prediction of crack tip stress concentration in thermoelectric elastic materials
Journal
International Journal of Mechanical Sciences
Journal Volume
304
Start Page
110736
ISSN
00207403
Date Issued
2025-10-15
Author(s)
Abstract
In semiconductor packaging, thermal and electrical loading during bonding, curing, or burn-in testing generates thermomechanical stresses that often result in cracks and reduced device reliability. This study advances the theoretical understanding of fracture behavior in n-type Bi₂Te₃ thermoelectric materials containing symmetric lip-type cracks by developing a novel analytical framework that accounts for combined mechanical and electrothermal loading at arbitrary angles. Through this model, stress intensity factors (SIFs), full-field stress distributions, and fracture angles are evaluated across varying loading orientations and crack geometries. A key innovation lies in demonstrating that tailored vertical compressive or horizontal tensile preloads can effectively suppress crack-tip stress concentrations induced by thermoelectric effects, with critical thresholds identified for practical application. When suppression is insufficient, the failure initiation and fracture direction can be accurately predicted using the strain energy density criterion (S-criterion), enabling targeted reinforcement to delay or prevent crack propagation. These findings offer novel and actionable strategies to mitigate crack growth during thermal cycling, thereby informing the design of more robust thermoelectric modules and semiconductor devices that operate under complex multiphysics interactions.
Subjects
Electrothermal coupling
Fracture angle
Fracture mechanics
Stress intensity factor
Stress suppression
Thermoelectric materials
Publisher
Elsevier Ltd
Type
journal article