October 16-17, 2008, Hotel Club Senator/Expovest

Conference Programme
View the conference/exhibition floor plan (PDF)

Thursday 16th October

13:30 – 17:30
Flexible Circuit Technology: Structures, Applications, Materials and Manufacturing Processes
Instructor: Joseph Fjelstad

Flexible circuits are arguably the world's most versatile electronic interconnection technology. Today products enabled by flexible circuit technology abound as flex circuits are now used in every imaginable way. This course will explore this increasingly important member of the electronics interconnection family as it evolves and changes to solve an increasing number of interconnection problems. Included will be reviews and discussions on applications, materials and processes as well as specific testing concerns. Also covered are the special design needs associated with flexible circuits as they are true electromechanical devices which require special knowledge to avoid costly errors. The material for this short course has been extracted from "Flexible Circuit Technology, 3rd Edition" which was written by the instructor.  

What you will learn

• Overview of flexible circuit technology 
• Flex laminate material options 
• Flex circuit structures
• Flex circuit design guidlines  
• Flex circuit manufacturing processes
• Steps to implementing flex in a design  
• Flex circuit testing and reliability concerns and factors
• Special flex circuit assembly needs
• New developments in flex 

Who Should Attend
This subject matter is of value to anyone in the electronics industry needing a better understanding of flexible circuit technology. Material suppliers, product engineers and managers, PCB designers, flex circuit buyers and those new to the electronics industry will particularly benefit.

13:30 – 17:30
Half-Day Workshop—"Reliability Issues for Lead-Free Soldering: Solder Joints, Printed Wiring Boards & Components"
Instructor: Werner Engelmaier

The likely switch to lead-free (LF) solders raises a number of issues and problems regarding the manufacture, processing, and reliability of electronic products using LF-solders.

In this course the reliability threats to the solder attachments themselves as well as to the printed circuit board (PCB) substrates and components will be discussed. These threats to reliability will be detailed as to the load drivers and the resulting failure modes, and illustrated by pertinent examples and illustrations.

Further, issues in the processing of electronic assemblies utilizing LF-solders arising from the higher soldering temperatures and the metallurgy of LF-solders will be highlighted and discussed.

Adequate reliability of surface mount solder attachments can only be assured with an understanding of all the factors impacting the loading conditions on the solder joints. Solder creep-fatigue behavior as well as the different load drivers such as thermal cycling, vibration, and mechanical shock are explained. The available information for LF-solders, which often is seemingly contradictory, will be put into context with the creep-fatigue behavior of tin-lead (Sn/Pb) solders.

The physics-of-failure and failure statistics information underlying the information for Sn/Pb solders in industry documents such as IPC-9701 "SMT Solder Joint Reliability Qualification and Performance Standard," IPC-SM-785 "Guidelines for Accelerated Reliability Testing of Surface Mount Solder Attachments," and IPC-D-279 "Design Guidelines for Reliable Surface Mount Technology Printed Board Assemblies" took over 30 years to develop. The available information for the creep-fatigue behavior of LF-solders is as yet inadequate for the determination of acceleration factors and the development of creep-fatigue models.

Appropriate testing, which has even more importance given the absence of available acceleration factors for LF-solders, to assess the extent of these various reliability threats will be suggested and discussed. Strategies to assure the reliability of the solder attachments, printed circuit boards (PCBs), and components in electronic product subjected to LF-soldering will be explained.

Friday  17th October

09:30 – 09:55
Keynote Speech – Joseph Fjelstad
Solderless Assembly of Electronics - A simpler approach to manufacturing?

The electronics industry has successfully used solder as the primary material for making electromechanical interconnections between components and circuit assembly for more than 60 years.

However, with the move to lead-free soldering, the long term reliability of electronics assemblies produced using lead-free solder has come into question.
In this environment, a method for fabrication electronics without solder has been introduced.

The new method, dubbed Occam in honor of the 14th century logician and advocate of simplicity, William of Occam, allows for electronics assemblies to be produced using less materials, fewer steps and with less energy than can be accomplished using current practices and it offers significant design freedom not possible otherwise.

This talk will provide an overview and perhaps a preview of the next wave of electronics manufacturing trends.     

10:00 – 10:25
Superior alloys for harsh environments
Gary Cunning, Cookson Technologies, Woking, UK

Automotive electronics modules are exempt from the EU RoHS legislation, which restricts the use of six elements in electronics assemblies, including the use of lead (Pb) in solder alloys. However, most manufacturers in this sector are investigating lead-free processes to help vehicle manufacturers meet the end of life vehicles (ELV) mandate, which encourages the use of lead-free assembly through strict labeling requirement and a limit on the total amount of lead in electronics assemblies in the completed vehicle.

One of the key challenges to automotive electronics manufacturers is the increasingly high operating temperature, as modules are placed closer to the point of use. The move towards electronics being placed into harsher environments is being driven by the desire to reduce wiring within the vehicle, which both adds weight and is in itself a reliability hazard. Standard lead-free alloys offer higher melting points and increased peak-operating temperatures compared to tin-lead, but have poor creep performance.

A major feature of the harsh environment faced by under-hood vehicle electronics is that the majority of operation time is conducted at elevated temperatures with a high level of vibration. This paper outlines the development of a high performance alloy designed to withstand these harsh conditions within the tough reliability requirements mandated by vehicle manufacturers.

10:30 – 10:55
Reliability and the impact of contamination in electronics production
Sheila Hamilton, Technical Director, Teknek

This paper will examine the impact of contamination on reliability, production yields and wastage on electronic assembly production.

As the electronics sector strives for zero defects, the presence of contaminants in the production process can lead to substantial rework, lower yields and greater wastage. The paper will look at how reliability can be improved by monitoring, controlling and eliminating contamination from the production process.

About the author:
Sheila Hamilton is technical director of Teknek, the global leader in contact cleaning technology for the electronics sector.  Sheila joined Teknek in 1987 as technical director after working as a product designer (yachting equipment) and power station engineer.  She has also run her own consultancy in the field of electronics component packaging.  Sheila has a BSc in Mechanical Engineering from Glasgow University and is currently studying for an MBA at Strathclyde University.  In addition, she is a recipient of two Smart Awards in the field of Electromagnetic Interference.

11:30 – 11:55
Effects of an Appropriate PCB Layout and Soldering Nozzle Design on Quality and Cost Structure in Selective Soldering Processes
Reiner Zoch, SEHO, Product Manager Selective Soldering

Globalization of markets results in stronger competition with clearly noticeably cost pressure. For companies producing electronic equipment, it is therefore of existential importance to reduce production costs whilst maintaining a consistently high quality level of the manufactured products. Manual repair soldering that is expensive, time consuming and cost intensive is already unacceptable due to the required quality and the reproducibility of the whole manufacturing process.

In more than 80% of cases, solder bridges are the main reason for faults. The solder's pull-off behavior, which is influenced by several factors, is what is mainly responsible for a bridge-free soldering result in the selective soldering process.

An appropriate printed circuit board design is of the utmost importance here. For example the shape of the pads and their distance in relation to each other can benefit—or with the corresponding design exclude—the formation of bridges. The distance between a pad to be soldered and an adjoining one that is not to be wetted also plays a role.

The distance between the individual pins, as well as the length of the pins, are likewise to be taken into account. If, for example, the length of the pin is too short, the peel strength of the liquid solder will not suffice to pull the solder away again from the solder joint. Solder bridges are already preprogrammed with this.

Moreover, by choosing the correct solder nozzle, one can avoid the formation of soldering faults in the automatic selective soldering process. The design of the solder nozzle, such as for example the shape or diameter, and the solder nozzle technology used, such as, for example, wettable and non-wettable solder nozzles, play a role here. Additional innovative features, such as debridging knives, can effectively avoid the formation of solder bridges, especially in the dip soldering process.

With many practical examples, this paper gives a detailed explanation of the individual points that should be found in the selective soldering process, with regard to the assembly design and solder nozzle technology. Moreover, the options for a faultless and cost effective electronic production will be shown here step by step.

12:00 – 12:25
Detecting counterfeit components – a suggested methodology
David Bernard, Dage Precision Industries, United Kingdom

As components become more expensive, obsolete or scarce and hard to find, it is a sad reality that this situation can be ruthlessly exploited by criminals supplying counterfeit items. However careful the supply chain process, the practical and desperate requirement to satisfy manufacturing output, coupled with the ease of internet searches, can often force manufacturers, or their suppliers, to have to look into the grey market. These issues are not just for the most expensive and exotic components, where concern for their quality is always present because of their cost: counterfeits exist for long-lead-time and obsolete devices with values below $10. Such low value items are, arguably, far more dangerous to the production quality of board manufacturers, with enormous resulting costs to reputation and business, as the time and cost associated with checking every item often cannot be warranted. Therefore, after initial checks on a small sample, for example off the end of the reel, such components can easily go straight into production but with the bulk of the reel being counterfeit.

This paper highlights that problems from counterfeit components are not limited to a small expensive niche of devices and provides some suggested guidelines for using different analytical and inspection techniques so as to minimize the risk that counterfeits bring. Techniques to be used include optical inspection, XRF, IR microscopy and x-ray inspection. It will also suggest a strategy for minimising the risk and illustrate a simple procedure for gathering information on parts to create a reference database.

12:30 – 12:55
Development of a novel lead-free solder for high reliability applications
Richard Boyle, Henkel Adhesives Ltd, Woodlane End, Hemel Hempstead, UK. Richard.boyle@uk.henkel.com

With the introduction of the lead (Pb) ban within the RoHS directive it soon became evident for the need of a high reliability alloy for use in high stress environments. Due to the nature of lead free alloys there was a fear that they could contribute to failures in high stress environments due to their hardness leading to reduced stress relief that the traditional lead containing alloys had previously given. To overcome this, a project was initiated by Siemens to develop an alloy that would overcome this issue. The Innolot project was launched with Henkel as a leading partner supplying alloys and soldering materials. The projects aims were to develop an alloy that had a lower melting point than the adopted standard SAC alloys to reduce the risk of damage to temperature sensitive components. But the alloy and resulting joints had to with stand higher operating temps of at least 150 centigrade and be not only lead free but contain no highly toxic elements.

The Innolot alloy was produced as a six-part alloy based on SAC but with the benefits as outlined above. The presentation will outline the development of this alloy and the benefits derived from it.

14:00 – 14:25
Cleanliness requirements prior to conformal coating
Renate Berenyi, Zestron Europe

The requirements on electronic assemblies used for high-tech applications in the automotive, military or aviation industry are constantly increasing. In order to guarantee an optimal long-term reliability of the entire assemblies, highest standards for the surface cleanliness are required. This ensures optimum adhesion of the coating even under extreme conditions. These standards can often only be met by integrating an additional cleaning process prior to conformal coating.

At CEMCONEX, ZESTRON will describe the requirements for the surface cleanliness of assemblies prior to conformal coating and will present fast and cost-effective test methods to analyze the cleanliness level.

14:30 – 14:55
Reducing Defects in Hand Soldering Operations
John Vivari / Philippe Mysson, EFD Inc. USA

Wire soldering operations are still widely accepted in the electronics assembly industry. When a product or the parts within cannot withstand the heat of oven reflow, the localized heat provided by a soldering iron has been the traditional solution. In high-volume operations, this can often require large labor pools to keep up with more automated assembly processes upstream or downstream. Soldering with wire and iron also leaves process judgments up to individual operators, and can produce a wide variety of defects, scrap, or long-term quality issues.

Despite the many improvements in automated soldering technology through the years, many soldering operations are best suited to manual production methods, which produce inconsistent results. Whether in low-volume custom operations or large-scale manufacturing processes, the quality of hand-soldered joints will exhibit a high degree of variation. Defect, scrap, and rework rates can be excessive, even when using skilled employees.

Higher temperature lead-free operations present an additional challenge. Because of the higher temperatures required, these processes have even smaller operating windows. Visual inspection of lead-free solder joints also presents new difficulties, and since most hand soldering rework occurs ‘on-the-fly,’ actual defect rates are difficult to measure.

There are other process solutions available that involve very little capital expenditure, but can significantly increase operator output. These solutions are effective in eliminating many of the process defects associated with wire solder. They will usually result in a faster and more controllable process that reduces scrap and improves overall product quality. In many applications where wire solder was once a requirement, a more automated approach can often be achieved using solder paste and localized heating methods.

15:00 – 15:25
The Perfect Storm
Marie Kaing, Humiseal Corporation

A hot topic right now is the effects of conformal coating to address dendritic and tin whisker growth.

As lead free becomes more popular certain combinations of alloys, flux and high frequencies are causing reliability issues.

The “perfect storm” can occur under the following conditions:

• High tin and silver bearing alloys
• Fine pitch tracking and components
• No clean production
• High frequency
• High power
• Heat
• Humidity
• No conformal coating

Can conformal coating prevent this? What are the options?

16:00 – 16:25
Innovative Engineered Cleaning Fluid Designed to Remove Process Soils from Stencils, SMT, and Rework in Batch and Inline Cleaning Equipment
Mike Bixenman, KYZEN Corporation

Electronics assemblers are challenged with a continuous stream of technology advances to improve performance and increase speed and efficiency. Electronics innovations are enabled by miniaturization of components and devices. In the age of no-clean and lead-free soldering, assemblers need manufacturing flexibilities to clean stencils, populated surface mount and through-hole assemblies, and re-worked boards. Engineering cleaning fluids are typically designed for specific equipment and applications. This paper introduces an innovative aqueous cleaning fluid designed for use in batch and continuous inline equipment that works for cleaning stencils, populated surface mount and through-hole assemblies, and re-worked boards.

16:30 – 17:00
Modern Manufacturing incorporating Process Control and Traceability
Torsten Vegelahn, EKRA, Germany

The economic success of a company in today’s market is primarily dependent upon how effectively the company uses its resources, particularly with regard to effective assignment of machines, effective use of materials, and quality awareness. This is particularly essential for the printing process, being a possible origin of a large amount of failures within the SMT production environment. For a company to continuously remain competitive, it needs efficient and versatile process control and traceability tools that can easily be adapted according to the company’s requirements. With the ASYS/EKRA identification solutions (1D, 2D, RFiD), along with a high performing inspection system, the printing process and its PCBs/substrates can be traced and controlled most effectively.

CEMCONEX is jointly organised by Global SMT & Packaging magazine and Hart Marketing International.