A Cost Effective Solution for Supporting Populated Circuit Boards during the Solder Paste Print Operation

Support tooling for circuit boards whose undersides are populated with electronic components is delicate,time
consuming to setup,and relatively expensive. This is because support pins or dedicated work holders have to avoid
applying direct and concentrated mechanical loads to electronic components located on the underside of the board.
A number of automatic pin adjustment solutions are currently available to PCB manufacturers,but these systems are
relatively expensive and some of them cannot be used without applying concentrated and potentially damaging loads
to the components. These systems are also sensitive to component placement variations. A new cost effective
method of supporting circuit boards during the solder paste print process has been developed. This study investigates
the performance of this new type of support in handling boards with components mounted on their underside as well
as unpopulated boards. This new support is in the form of a gel made of a polyurethane elastomer. The gel board
support is compared to a conventional board support solution.

Author(s)
Anand Bhosale,Daryl L. Santos,Gerald Pham-Van-Diep,John Morini,Randy Peckham
Resource Type
Technical Paper
Event
IPC APEX 2003

Study of Assembly Processes for Solder Flip Chips on FR-4 Substrates

Flip chip assembly is a key capability to enable product miniaturization. Our previous studies have investigated several flip chip
interconnection types including anisotropic conductive film or paste,and Au-Au thermosonic bonding. This project is focused
on the assembly of 0.200 and 0.250 mm pitch solder flip chip devices. Two methods of applying flux for the flip chip are
investigated: the dip fluxing method,and the jet fluxing of the substrate. The placement accuracy of a traditional SMT pick and
place system (upgraded for flip chip) is investigated and results discussed. The impact of the reflow process in air vs. nitrogen is
examined. Two underfill materials are evaluated for compatibility with the flux. Results of reliability testing (including thermal
cycling,mechanical shock and vibration) will be presented.

Author(s)
David A. Geiger,Jonas Sjoberg,Patrick Wong,Dongkai Shangguan
Resource Type
Technical Paper
Event
IPC APEX 2003

A Simpler Approach to Cost-Effective Solder Paste Testing

The increasing demand for portable electronic
products has accelerated the quest for even greater
miniaturization. At the current state of electronic
production technology,volume and weight
reductions have been achieved through the
application of SMT and Direct Attach components.
One result has been a tremendous increase in solder
paste usage. The world market for this material is
predicted to increase from US $679M in 2000 to
approximately US $2Billion by the year 2007.1
The proper performance of solder paste in forming
physical and electrical connections is vital to the
quality and reliability of SMT assemblies.
Unfortunately,most end users of solder paste have
limited knowledge and equipment for comprehensive
and in-depth evaluation of solder paste to ensure
optimum quality.
The increasing application of solder paste calls for
serious consideration its importance within the
context of quality management systems such as
TQM,ISO 9001 and QS 9001. Particularly when
process improvements are required through SPC or
other tools,the understanding of solder paste quality
issues becomes a requirement.

Author(s)
Ineke Van Tiggelen-Aarden
Resource Type
Technical Paper
Event
IPC APEX 2003

AOI in EMS

As outsource to EMS,the requirement for Automated Optical Inspection (AOI) equipment changes as well. Due to
the diversity of the business,EMS providers require equipment that can handle a myriad of different components.
The need for frequent programming,program portability and repeatability,and the establishment of common
equipment platform become more important than before. To understand the capability of current AOI technology,
equipment from four manufacturers were installed at a test site for a post-reflow benchmark test. Two test vehicles
were used for eight different tests. Test results were recorded and analyzed. Each machine was rated for its
performance in each individual test. The result shows that no single machine outperforms others in every category.
The best performance from each category is,99.89% portability for general SMT components,99.95% for small
chips,99.16% for program repeatability,84% defect detection rate,and 28-second inspection cycle time for
motherboard type assembly. Angle measurement was performed on three machines. The model with best
performance reported the measurement within 1° difference. Based on the overall test results,AOI can be
considered an efficient tool for catching post reflow defect and improving process yield. As the renovation continues
in AOI technology during the past few years,we should expect to see an increase in AOI implementation in the
EMS industry.

Author(s)
Steven Perng
Resource Type
Technical Paper
Event
IPC APEX 2003

Automated Design Verification using DFM/DFT

In a low-volume,high-mix electronics manufacturing environment,the ability to delineate design concerns before a
customer’s product goes to production is paramount. Design deficiencies or deviations from standards,or designs
that don’t accommodate manufacturing and testing capabilities could cause significant levels of manufacturing
defects and may affect several downstream parameters such as process yield and product reliability. Correcting
problems during the manufacturing phase involves significant expenditure vis-à-vis repair,rework and scrap. In
order to avoid this expense,an effective and efficient (automated) tool is required to scrutinize designs and to
categorize any deviations from the standards,long before the design reaches the production floor. In order to
perform such checks,the tool must refer to an accurate and exhaustive set of rules that can cover all critical aspects
of manufacturing and testing. Moreover,these rules must cover all designs and should also be updateable.

Author(s)
Hrushikesh Jadhav,Robert Murcko,Krishnaswami Srihari,Mark Brinthaupt,Michael Testani
Resource Type
Technical Paper
Event
IPC APEX 2003

Integrated Forecasting Across Value Chain

The internet explosion of the 90’s created much hype around public exchanges that has never materialized. The
current business environment of a multi-company value chain,alliances and partnership selling has highlighted the
need for increased value chain collaboration around critical supply chain functions like forecasting. This has created
the need for a public exchange-like solution,but with focused ownership from a majority stakeholder. This paper
presents a collaborative solution that illustrates the benefits of integrated forecasting. Our belief is that the solution
has to be sponsored and maintained by the majority stakeholder (most likely the OEM) to ensure active participation
by the value chain members.

Author(s)
William Poston,Tom Velema,Santosh Anoo
Resource Type
Technical Paper
Event
IPC APEX 2003

Applying Automation to the NPI Process

With the increase in outsourcing activity throughout the electronics industry,OEM’s are turning to Electronic
Manufacturing Services (EMS) to provide quality quick turn prototypes and fast New Product Introduction (NPI).
The differentiator between success and failure in the EMS marketplace is the data and the automation that can be
done to streamline data entry and eliminate duplicate data sources and data entry errors. This difference is usually in
the data; whether OEM or EMS the requirement for accurate and complete data has become the standard. Data and
Process Transparency can help transform Front-end engineering NPI from an emphasis on quick-turn prototyping
into a gateway to volume production,but there will need to be a change in perception with regards to how data and
process information are treated and handled.

Author(s)
Anton Krycuk,Corey Peterson
Resource Type
Technical Paper
Event
IPC APEX 2003

EMS/OEM Interaction: Maximizing Benefit by Optimizing Communication

The relationship between the OEM and the EMS provider (Electronic Manufacturing Services) has evolved with the
increase in outsourcing of manufacturing services. This has resulted in the consequent evolution of the quality and
quantity of data provided by the OEM to the EMS provider. This paper examines the OEM/EMS interaction with
emphasis on the engineering data related to PCBA (Printed Circuit Board Assembly) operations provided by the
OEM to the EMS provider. It will show how the format and content of data affects the integrity of the manufactured
product and the level of services that the EMS provider can offer the OEM.

Author(s)
Rahim Jivraj,David Lee
Resource Type
Technical Paper
Event
IPC APEX 2003

OEM/EMS NPI Collaboration: Optimizing the Design and NPI Supply Chain to Improve Time-To-Volume Manufacturing

The outsourcing trend within the electronics industry continues to accelerate as OEMs focus their limited resources on core
competencies that enhance shareholder value. This outsourcing trend is driving OEM Design and NPI Supply Chains to
become increasing horizontal,triggering them to recognize that their ability to leverage their supply base is a critical element
in their business model. These companies have recognized the need to craft a design and NPI supply chain that leverages
their internal strengths with the core competencies of their supply base. This paper presents the key characteristics of a
successful OEM/EMS NPI collaboration,including the creation of a NPI process framework. The key elements of this NPI
process framework include:
• OEM/EMS process alignment - developing a common NPI process language
• Alignment on business models,core competencies,technology roadmaps that create a "win-win" partnership
• Early engagement (concept/feasibility phases of the OEM NPI process)
• OEM/EMS executive sponsorship
• Discipline and accountability around:
• Conducting reviews
• Overall project management
• Communication plans
• Product collaboration tools and data standards
• Design for X that encompasses the complete design and supply chain (e.g.,assembly,test,reliability,safety,cost,
logistics,environment,etc).
The paper addresses the benefits and challenges of establishing and implementing a collaborative OEM/EMS NPI process
framework. Case studies of successful implementations / lessons learned will be provided.

Author(s)
Jon Eckhoff,Paul Rice
Resource Type
Technical Paper
Event
IPC APEX 2003

Can One Effectively Clean Under Low Stand off Components (<4 MIL or 0.004 Inches)?

With the ban of CFC’s,various cleaning processes have emerged and have been established as viable
alternatives1,2,3. Several cleaning processes such as ultrasonic and spray in air batch and in-line have become
firmly established. Each equipment type typically has its advantages and disadvantages,which will obviously be
of different significance to the end-user.
This in-depth study sets out to determine,which mechanical agitation cleaning system might demonstrate the
best cleaning results with regard to cleaning performance. To address the most currently available technologies:
ultrasonic,pressurized spray-in-air,spray-under-immersion,and centrifugal cleaning systems were taken as a
representative basis.
In order to guarantee meaningful results,the most demanding application was chosen: the cleaning under large
surface components. A significant conclusion of the study is that the cleaning chemistry is significantly more
important than the equipment technology used.

Author(s)
Andreas Muehlbauer,Helmut Schweigart,Stefan Strixner
Resource Type
Technical Paper
Event
IPC APEX 2003