Moisture-Driven Electromigrative Degradation in Microelectronic Packages

Siah, L.F.

doi:10.1007/978-1-4419-5719-1_20

Cited by 8 publications

(4 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The weakest link in the entire assembly, currently, was the interface between the epoxy plated with copper and the solder. Defects of this interface are currently a cause for major reliability concerns in the electronics industry, and can include electrochemical migration (ECM) and crack growth (Siah, 2010; Gurumurthy et al , 2001; Noh and Jung, 2008). The presence of moisture can lead to the failure of the interface during high temperature processing and long‐term failure of the interface due to sub‐critical crack growth (Gurumurthy et al , 2001; Noh and Jung, 2008; Katayanagi et al , 2000; Jensen et al , 2000).…”

Section: Resultsmentioning

confidence: 99%

Failure mechanism of solder bubbles in PCB vias during high‐temperature assembly

Chen

Zhou

et al. 2013

Circuit World

View full text Add to dashboard Cite

Purpose -Pb-free soldering challenged printed circuit board (PCB) assembly with high temperature. The purpose of this paper is to explain the failure mechanism of printed circuit board (PCB) assembly with solder bubbles of vias to avoid the problems of via-drilling defects and solder joint failure. Design/methodology/approach -The failure of PCB vias with solder bubbles was investigated through cross sections and SEM microstructure inspection, TMA measurement, moisture absorption analysis and DSC measurement. The moisture absorption and CTE of FR4 laminate matched with manufacturing requirement to avoid the effects of solder bubbles. The effects of via drilling with a dull drill bit were compared to that with a new drill bit. Findings -The moisture absorbed inside holes of via plating layers could be exposed to induce solder bubbles during Pb-free soldering assembly and dull drill bits should be prevented during the drilling process to avoid the no-bearing drilling effects. Originality/value -The failure of PCB vias is not only involved in the voiding in solder joints but manufacturing processes of PCB. The paper designs an approach to analyse the properties of PCB materials and the drilling effects of vias to find out the mechanism resulting in solder bubbles of vias. The problem of drill bits should be considered to prevent the moisture absorbed in drilling vias with defects.

show abstract

Section: Resultsmentioning

confidence: 99%

Failure mechanism of solder bubbles in PCB vias during high‐temperature assembly

Chen

Zhou

et al. 2013

Circuit World

View full text Add to dashboard Cite

show abstract

“…Entrapped moisture in packaging materials is directly responsible for the significant increase in the internal vapor pressure during high temperature reflow, which often leads to interfacial cracking and delamination, or "popcorn" type of failure [10]. In addition, in the presence of moisture and high temperature, and under an applied electric field, electrochemical migration (corrosion) of metals is another major failure mechanism [24]. Thus, understanding moisture diffusion and hygroscopic swelling behavior becomes the first step in mitigating the risk of moistureinduced failures.…”

Section: Introductionmentioning

confidence: 99%

In-situ characterization of moisture absorption-desorption and hygroscopic swelling behavior of an underfill material

2011

2011 IEEE 61st Electronic Components and Technology Conference (ECTC)

View full text Add to dashboard Cite

Moisture absorption and hygroscopic swelling behavior of an underfill material were measured in-situ using the sorption TGA and the DMA-RH techniques, respectively. Results showed that moisture diffusion can be well described by Fick's law when the relative humidity (RH) is 60% or less, and the diffusivity exhibits an Arrhenius temperature dependence with an activation energy of ~ 0.56 eV. At 85% RH, non-Fickian diffusion behavior becomes apparent in the latter stage of the diffusion process. Increase in the saturated moisture content (C sat ) at 60%RH was observed after exposure at 85°C 85%RH, which is attributed to hygrothermal ageing induced damage in the material. In-situ DMA-RH results showed that hygroscopic swelling strain is significant comparing with the thermal expansion of the material, and the swelling strain at 60°C 60%RH is equivalent to the thermal strain over a ∆T of 100°C for T < T g . The coefficient of hygroscopic swelling (CHS) was calculated and the results showed that CHS is temperature dependent, and it increases with the increasing temperature. At higher humidity condition (85%RH or higher), the swelling strain deviates from its linear dependence on C sat and it increases faster than linear when C sat increases, which may also be attributed to hygrothermal ageing induced damage in the underfill material.

show abstract

“…The current development of the multiple functionality and miniaturization of printed circuit boards (PCBs) increases the possibility of electrochemical migration (ECM). ECM is a phenomenon of great importance in relation to failures of PCB assemblies and can result in the growth of the conductive filaments (generally called dendrites) through an electrolyte solution under hot and humid environment . As a result of the ion migration and dendrites growth, the surface insulation resistance (SIR) of the PCBs decreases significantly, which leads to a short circuit in the device and even catastrophic failure.…”

Section: Introductionmentioning

confidence: 99%

“…In addition, the moisture provides the aqueous medium for ion migration . The majority of insulation failures attributed to humidity are related to the formation of the conductive moisture path, which is also the fundamental precondition for ECM on surfaces and interfaces . Besides, the humidity also provides conditions for metal dissolution and dendrite growth in the process of ECM.…”

Section: Introductionmentioning

confidence: 99%

Humidity Threshold Model of Numerical Control Multilayer Printed Circuit Board for Electrochemical Migration

Xie

Tang

Chen

et al. 2014

Quality & Reliability Eng

View full text Add to dashboard Cite

In this paper, numerical control finished boards are employed as test samples to evaluate the effects of the environment and bias voltage on the surface insulation resistance of printed circuit boards. The results indicate that the surface insulation resistance degradation processes leading to failure exhibit a relative humidity threshold value, which is mostly related to temperature, test patterns, and bias voltage. Then, a humidity threshold model is built on the basis of electrochemical migration to quantify the relationship between the relative humidity threshold and conductor spacing and bias voltage under the controlled environments. Finally, experiments and tests have been carried out to validate the effectiveness and practicability of the model. Furthermore, the residual analysis is applied to check the fitting effect of the proposed model. According to the new model, the humidity threshold value can be obtained to provide the guidance for reliability problems in application. It is crucial to the design and deployment of reliable printed circuit boards. . Her main research interests include reliability analysis, reliability testing, reliability assessment, and reliability growth on numerical control system.Hangjun Zhang holds a Masters degree in Mechanical Engineering from the Tianjin University of Technology and Education, Tianjin, China. He is also a member

show abstract

Moisture-Driven Electromigrative Degradation in Microelectronic Packages

Cited by 8 publications

References 27 publications

Failure mechanism of solder bubbles in PCB vias during high‐temperature assembly

Failure mechanism of solder bubbles in PCB vias during high‐temperature assembly

In-situ characterization of moisture absorption-desorption and hygroscopic swelling behavior of an underfill material

Humidity Threshold Model of Numerical Control Multilayer Printed Circuit Board for Electrochemical Migration

Contact Info

Product

Resources

About