Effects of Nano-Tio2 Particles Additions on Microstructure Development And Hardness of Sn3.5Ag0.5Cu Composite Solder

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The effects of nano-TiO particle additives on the microstructure and microhardness of the 2 Sn3.5Ag0.5Cu composite solder were studied. Results show that alloying with nano-TiO 2 particles dramatically reduced the formation of primary ß-Sn phase,the average size of Ag3Sn phase,and the spacing lamellae in the Sn3.5Ag0.5Cu composite solder. This is attributed to the adsorption of nano-TiO2 particles with high surface free energy on the grain surface during solidification. Microhardness improved with the addition of nano-TiO 2 particles,which refinded Ag Sn INCs. The refined IMCs acted as a strengthening phase in the 3 solder matrix and enhanced the Vicker’s microhardness of the Sn3.5Ag0.5Cu composite solders,which corresponds well with the prediction of the classic dispersion strengthening theory.

Author(s)
Lung-chuan Tsao
Resource Type
Technical Paper
Event
IPC Midwest 2010

Reliability and Quality Planning in the Product Development Cycle

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In globally competitive markets,managing product quality,reliability and risk is not an option. However,it also brings its own unique set of challenges to complex organizations:
- Product design teams need to gain early insight into product reliability - A systematic process is needed to plan for quality,and to identify and mitigate risks - The product design must be more closely aligned with customer requirements - Reliability and quality must be balanced with lifecycle costs and profitability - A centralized system is required to enable guided corrective actions and prevent repeat issues Today,many companies struggle with these demands,creating fragmented tools and processes that delay analysis and prevent communication,the consequences of which range from undesirable to catastrophic,including: Escalated costs,undetected risks,product recalls,decreased consumer confidence,and loss of market share. Customer demands and government oversight have never been greater,which is further amplified with 24 hour access to consumer blogs and media coverage. Every corporate boardroom is forced to consider the
impacts of quality,reliability and risk on their business.

Author(s)
Santanu Roymoulik
Resource Type
Slide Show
Event
IPC Midwest 2010

Leveraging IPC 1752 for Product Lifecycle Analytics

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- Regulations are driving increasing IPC-1752 use
- More restricted substances and product categories in scope
- The business challenge is much bigger than “regulatory compliance”
- Teams increasingly manage multiple,evolving standards
- Business goal: Early visibility
- How? Systematically acquire,validate,and maintain environmental data
- Progressive disclosure
- Required: Data Management and Systems Integration
- Enabling continuous data acquisition & analysis
- Compliance Summary: Key Business Needs
- Product Environmental Performance is the next wave
- Driver: Product environmental footprint
- Life Cycle Environmental Impact
- Extended BOM for LCA Modeling and Regulatory Compliance

Author(s)
Jorgen Vos
Resource Type
Slide Show
Event
IPC Midwest 2010

Improving Tin Whisker Testing through Quantitative Measurements of Plated Film Properties

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- Correlating film properties to the propensity to whisker will lead to the development of a comprehensive whisker growth model and create successful mitigation strategies.
•Hillock and whisker growth have been correlated to measureable film properties
–Film stress evolution
–Grain boundary mobility
–Crystallographic texture evolution
•Film properties are influenced by basic processing parameters
–Electrolyte type
–Electrolyte additives
–Deposition current density
–Film thickness

Author(s)
Aaron E. Pedigo
Resource Type
Slide Show
Event
IPC Midwest 2010

Management and Mitigation of Tin Whiskers for Lead-Free Electronics

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The lead-free directive from the EU has created a number of challenges for high reliability electronic applications. Key among those challenges is the need to address the issue of tin whiskers. While complete elimination of the tin whisker phenomenon on tin finished materials is not possible there are steps that can be taken to manage and mitigate the creation and effect of tin whiskers. Delphi has focused on mitigation steps to reduce the likelihood of tin whisker occurrence and has implemented processing measures to reduce the potential for damage by tin whisker that do occur. Those mitigation steps and findings from validation work and product performance reviews are shared.

Author(s)
Samuel Platt
Resource Type
Slide Show
Event
IPC Midwest 2010

Drop Testing of a Pb-Free Board after Assembly and SnPb-Rework

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•Board-level drop shock test was performed on 9 assemblies
–63 parts / board
–Parts representative of military package styles
•Assembled on Pb-free compatible laminate with SAC 305 solder
•Selection of the non-BGA parts reworked with SnPb solder
•Metallurgical characterization
•Assemblies fixtured to drop table and subjected to 500Gs for a total of 20 drops
•In-situ shock response,net resistance and strain recorded
•Physical FA performed to characterize mechanical damage

Author(s)
Eva Kosiba
Resource Type
Slide Show
Event
IPC Midwest 2010

Void or Not to Void

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- Background: What is a void?
- What is a "macro" void?
- What is a “planar” void?
- What is a “shrinkage” void?
- What is a “microvia” void?
- What is a “pinhole” void?
- What is a “Kirkendall” void?
- Macro voids: Good or Bad?
- Is it possible to make voids on demand?
- Let’s Make a Void (or Not) 5 Years Later

Author(s)
D. Hillman,B. Christian
Resource Type
Slide Show
Event
IPC Midwest 2010

Addressing the Challenge of Head-in-Pillow Defects in Electronics Assembly

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The head-in-pillow defect has become a relatively common failure mode in the industry since the implementation of Pb-free technologies,generating much concern. A head-in-pillow defect is the incomplete wetting of the entire solder joint of a Ball-Grid Array (BGA),Chip-Scale Package (CSP),or even a Package-On-Package (PoP) and is characterized as a process anomaly,where the solder paste and BGA ball both reflow but do not coalesce. When looking at a cross-section,it actually looks like a head has pressed into a soft pillow. There are two main sources of head-in-pillow defects: poor wetting and PWB or package warpage. Poor wetting can result from a variety of sources,such as solder ball oxidation,an inappropriate thermal reflow profile or poor fluxing action. This paper addresses the three sources or contributing issues (supply,process & material) of the head-in-pillow defects.
It will thoroughly review these three issues and how they relate to result in head-in-pillow defects. In addition,a head-in-pillow elimination plan will be presented with real life examples will be to illustrate these head-in-pillow solutions.

Author(s)
Mario Scalzo
Resource Type
Slide Show
Event
IPC Midwest 2010

HDI Training & Implementation at Eagle Test Systems

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Eagle Test Systems (ETS) a Teradyne Company established a team during 2009 to develop a training exercise that would bring High Density Interconnect (HDI) knowledge to new products. A digital module was chosen as a redesign candidate to convert from standard printed circuit board technology to HDI with the help of an experienced third party CAD design house (DDI). The goal of the project was to take the existing digital module and reduce its mechanical size and features by approximately 50%; while maintaining or improving its electrical characteristics. One successful prototype lot was designed,fabricated,assembled,tested,and compared to the existing product performance. The design and fabrication process utilized while performing these tasks was documented and used to train ETS CAD designers,product development,manufacturing,and test engineers on HDI technologies.

Author(s)
Ron Evans,Todd Henninger
Resource Type
Technical Paper
Event
IPC Midwest 2010

Weigh/Bake/Weigh Testing To Determine Moisture Content in Printed Boards

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Entrapped moisture within printed boards can expand during soldering operations,causing delamination or other damage. Available methods for determining moisture content may be destructive
or non-destructive,and vary considerably in accuracy,equipment cost,and ease of use. This study assesses the methodology in the new test method IPC-TM-650 Method 2.6.28,and its applicability to
the recently published IPC-1601 "Printed Board Handling and Storage Guidelines." Moisture content was measured on samples of printed boards from various manufacturers,with differing laminate materials,constructions,and board thicknesses. Limitations and advantages of this test method are presented.

Author(s)
Joseph E. Kane
Resource Type
Slide Show
Event
IPC Midwest 2010