Reliability Assessment of Thermocompressed Epoxy Molding Compound through Glass via Interposer Architecture by the...

Area of Science:

• Materials Science and Engineering
• Mechanical Engineering
• Semiconductor Manufacturing

Background:

• Glass interposer architectures are crucial in advanced electronic packaging.
• Thermocompression bonding and molding shrinkage introduce significant mechanical stress.
• Metal-filled vias in glass interposers pose a risk for cracking and device failure.

Purpose of the Study:

• To investigate the mechanical responses and reliability issues in glass interposer assembly.
• To develop and validate a finite element-based submodeling approach for complex interposer structures.
• To analyze stress generation mechanisms, including thermal loading and material shrinkage.

Main Methods:

• A finite element-based submodeling technique was employed to handle modeling complexity and convergence issues.
• Convergence analysis determined the necessary local simulation model size (at least four via pitch-wide regions).
• Separate investigations into stress generation during thermocompression, coefficient of thermal expansion mismatch, and curing shrinkage.

Main Results:

• The submodeling approach provided stable simulation results.
• Critical stress concentrations were identified at the outer corner of the chip.
• Maximum first principal stresses reached 34 MPa on the chip and 120 MPa on the glass interposer during thermocompression.

Conclusions:

• The finite element submodeling approach is effective for analyzing stress in glass interposer assemblies.
• Understanding stress mechanisms is vital for mitigating cracking and ensuring the reliability of electronic packages.
• The identified stress levels and locations provide critical data for design optimization and failure prevention.