ABSTRACT
There are many failure mechanisms in hybrids, which could be grouped as follows:
1. Internal
• Electrical overstress caused by voltage, current or power higher than maximum allowed by design
• Thermal-mechanical overstress resulting in loss of adhesion of die, tabs and substrates, and integrity of wire bonds caused by
- incompatibility of materials
- temperature cycling
- thermal shock
- excessive operating temperatures
• Chemical contamination resulting in corrosion, electrical shorts, open wire bonds caused by
- contaminated solvents
- inadequate material and process controls
2. External
• Electrostatic Discharge (ESD) caused by absence of
- conductive storage containers and antistatic bags
- conductive storage mats
- grounded wrist straps
- grounded work benches
- humidity control
- ionized air
- grounded assembly and test equipment
• Vibration
• Mechanical shock
• Electromagnetic Interference (EMI)
• Inadequate storage conditions and temperature
• Package deformation during mounting in the system caused by excessive torque or inadequate flatness of the seating plane
• Hermeticity failure due to handling of I/O leads
• Operating environmental medium - oils, salt, etc.
