FSI implications of EMC rheological properties to 3D IC with TSV structures during plastic encapsulation process

2022

ARFMTS

LED technology has been evolving aggressively in recent years from incandescent bulb during older days to as small as chip scale package. There is tremendous pressure to stay competitive in the market by optimizing products to next level of performance and reliability with shortest time to market. This changes the conventional way of product design and development to virtual prototyping by means of Computer Aided Engineering (CAE). The objective of the paper is to review challenges in chip scale packaging application in LED technology. The first part of the paper covered the literature survey of Chip Scale Packaging (CSP) in Light Emitting Diodes (LED), CSP architecture challenges, molding process and material for CSP. The findings of literature found that very few researchers had study silicone encapsulations process in CSP for LED in term of material characterization, mold process and simulation. Findings also shows that deployment Computational Fluid Dynamic (CFD) and integration of virtual prototyping using Finite Element Analysis (FEA) in product development in CSP for semiconductor industry had greatly reduced the time to market. However, there are very few papers discuss the application for CSP technology in LED industry. Second objective of the papers is discussion of methodolology in molding material characterization and simulation methodology. CFD helps to simulate the flow pattern of molding material as a function of different temperature, molding parameters settings for voids and displacement. FEA also help to evaluate the deformation of silicone in panel form and enable designer to predict the displacement of devices with different silicone.

Section: Characterization Of Encapsulating Materials For Led and Elec...mentioning

confidence: 99%

A Review of Moldflow and Finite Element Analysis Simulation of Chip Scale Packaging (CSP) for Light Emitting Diode (LED)

Ching

2022

ARFMTS

“…where u, v, and w are the velocity vectors in the x, y, and z directions, respectively. The momentum conservation equation for 3D Newtonian fluids is expressed as (Ong et. al 2012b):…”

Section: Governing Equationsmentioning

confidence: 99%

Effects of Temperature on the Wave Soldering of Printed Circuit Boards: CFD Modeling Approach

Aziz

Khor

et al. 2016

JAFM

Self Cite

This study investigated the effects of temperature on the wave soldering of printed circuit boards (PCBs) using three-dimensional finite volume analysis. A computational solder pot model consisting of a six-blade rotational propeller was developed and meshed using tetrahedral elements. The leaded molten solder (Sn63Pb37) distribution and PCB wetting profile were determined using the volume of fluid technique in the fluid flow solver, FLUENT. In this study, the effects of five different molten solder temperatures (456 K, 473 K, 523 K, 583 K, and 643 K) on the wave soldering of a 70 mm × 146 mm PCB were considered. The effects of temperature on wetting area, wetting profile, velocity vector, and full wetting time were likewise investigated. Molten solder temperature significantly affected the wetting time and distribution of PCBs. The molten solder temperature at 523 K demonstrated desirable wetting distribution and yielded a stable fountain profile and was therefore considered the best temperature in this study. The simulation results were substantiated by the experimental results.

“…The material and thermal properties are summarized in Tables I and II, respectively. No slip condition was set for all structural surfaces (Ong et al, 2013). Therefore, the tangential velocity component was zero relative to the component surface.…”

Section: Structural Modelingmentioning

confidence: 99%

Thermal fluid-structure interaction of PCB configurations during the wave soldering process

Aziz

Soldering &Amp; Surface Mount Technology

Khor

2015

Self Cite

Purpose – This paper aims to investigate the thermal fluid–structure interactions (FSIs) of printed circuit boards (PCBs) at different component configurations during the wave soldering process and experimental validation. Design/methodology/approach – The thermally induced displacement and stress on the PCB and its components are the foci of this study. Finite volume solver FLUENT and finite element solver ABAQUS, coupled with a mesh-based parallel code coupling interface, were utilized to perform the analysis. A sound card PCB (138 × 85 × 1.5 mm3), consisting of a transistor, diode, capacitor, connector and integrated circuit package, was built and meshed by using computational fluid dynamics pre-processing software. The volume of fluid technique with the second-order upwind scheme was applied to track the molten solder. C language was utilized to write the user-defined functions of the thermal profile. The structural solver analyzed the temperature distribution, displacement and stress of the PCB and its components. The predicted temperature was validated by the experimental results. Findings – Different PCB component configurations resulted in different temperature distributions, thermally induced stresses and displacements to the PCB and its components. Results show that PCB component configurations significantly influence the PCB and yield unfavorable deformation and stress. Practical implications – This study provides PCB designers with a profound understanding of the thermal FSI phenomenon of the process control during wave soldering in the microelectronics industry. Originality/value – This study provides useful guidelines and references by extending the understanding on the thermal FSI behavior of molten solder for PCBs. This study also explores the behaviors and influences of PCB components at different configurations during the wave soldering process.