Reliability Packaging Testing
PhD student: Bin Su ([e-mail]) Advisor: Dr. Jianmin Qu ([e-mail]) Packaging Research Center Georgia Institute of Technology 6/16/2004
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Introduction to package reliability testing (1)
FAILURE MODES AND MECHANISMS
Chemical failure
Corrosion
Physical failure
Physical aging of polymers Electromigration
Thermomecanical failure
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Introduction to package reliability testing (2)
Heat Sink Adhesive Delamination Underfill Delamination Substrate Failure Solder Fatigue Failure Die Cracking
PCB Interconnection Failure
TYPICAL THERMOMECHANICAL FAILURES
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Introduction to package reliability testing (3)
Accelerated Testing The designed service life for many electronic products are too long to allow for reliability testing under actual service conditions.
Commonly accepted accelerated stress conditions Thermal Cycling and Thermal Shock Steady State Thermal Soaking (Backing, Dwell) Mechanical Vibration Voltage Extremes & Power Cycling High Humidity and High Pressure Combinations of the Above
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Electro-Mechanical property of solder materials (1)
Dog bone shape creep/fatigue loading with noncontact strain measurement
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Electro-Mechanical property of solder materials (2)
0.08 0.07
Strain/Unified Resistivity
0.06 0.05 0.04 0.03 0.02 0.01 0 -0.01 0
Unified Resistivity Change Strain
2000
4000
6000
8000
10000
Time system
Typical (s)
Test result: strain with resistivity. Creep load, Sn/3.8Ag/0.7Cu solder
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Electro-Mechanical property of solder materials (3)
1.2 1.18 1.16 Resistivity Change 1.14 1.12 1.1 1.08 1.06 1.04 1.02 1 0 1000 2000 Time (s) 3000 R/R0 TorqueAmp 9 8 7 Torque (N-m) 6 5 4 3 2 1 0 4000
Typical result: torque with resistivity. Daisy chain specimen under fatigue Constant angle torsion loading, torsion loading Sn/3.8Ag/0.7Cu solder
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Isotropic conductive adhesive modeling (1)
A 3-D model with uniform spherical particles is considered The electrical conduction is provided by the filler network
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Isotropic conductive adhesive modeling (2)
A resistor network is formed by all the contact resistances between particles. The bulk resistance can be obtained by solving the resistor network.
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Isotropic conductive adh...