Lattice Boltzmann Method of Different BGA Orientations on I-Type Dispensing Method
Aizat Abas1, Z L Gan1, M H H Ishak1
1School of Mechanical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang, Malaysia.
Plos One
|July 26, 2016
Summary
This study simulates fluid flow in ball grid arrays (BGAs) for underfill encapsulation. Lattice Boltzmann Method (LBM) accurately captures micro-voids and reveals orientation effects on filling time and pressure, enhancing package reliability.
Area of Science:
- Computational fluid dynamics
- Materials science and engineering
- Semiconductor packaging technology
Background:
- Underfill encapsulation is critical for semiconductor package reliability.
- Accurate simulation of fluid flow in ball grid arrays (BGAs) is essential for process optimization.
- Solder bump arrangement significantly influences fluid dynamics during encapsulation.
Purpose of the Study:
- To investigate the three-dimensional (3D) simulation of fluid flows through BGAs during underfill encapsulation.
- To analyze the impact of different BGA solder bump arrangements on flow front, pressure, and velocity.
- To validate simulation results using experimental data and the Finite Volume Method (FVM).
Main Methods:
- Three-dimensional computational fluid dynamics (CFD) simulations.
- Lattice Boltzmann Method (LBM) for fluid flow modeling.
- Finite Volume Method (FVM) for validation.
- Experimental observation for comparison.
Main Results:
- LBM simulations accurately captured micro-void formation, unlike FVM.
- Fluid filling time increased with perimeter, middle empty, and full BGA orientations.
- Perimeter orientation resulted in higher fluid pressure in the BGA's middle region.
Conclusions:
- LBM is a highly accurate method for simulating underfill encapsulation in BGAs, capable of capturing micro-voids.
- BGA solder bump arrangement critically affects encapsulation dynamics and filling times.
- Optimized BGA design and LBM simulations can improve semiconductor package reliability.
