Electronics Manufacturing Technical Articles

Two-Photon Polymerization: A New Approach to Micromachining

Jul 24, 2007 | Andreas Ostendorf, Boris N. Chichkov, Laser Zentrum Hannover eV.

The rapid technical development of ultrashort laser systems is creating exciting possibilities for very precise localization of laser energy in time and space. These achievements have triggered novel laser applications based on nonlinear interaction processes. A promising three-dimensional microfabrication method that has recently attracted considerable attention is based on two-photon polymerization with ultrashort laser pulses....

Publisher: Aerotech, Inc.

Reduced Oxide Soldering Activation (ROSA)

Jul 19, 2007 | Sam Pepe, Chemist, American Competitiveness Institute / EMPF

ROSA is a surface restoration technique that removes hard to reduce species like metal oxides or sulfides. At the time of its development, the focus was on solderability and compliance to environmental regulations. Industry trends and regulatory changes as a result of the Montreal Protocol were the driver for much of the concern over environmental compliance. The result was an increase in the development of no-clean and water soluble fluxes and the removal of halogenated cleaning chemistries....

Publisher: Electronics Manufacturing Productivity Facility (EMPF)

Implementing Lead Free Soldering - European Consortium Research

Jul 12, 2007 | Dr. M. Warwick.

Over the last ten years, there have been a large number of publications describing work into lead free electronics soldering. They have come from all regions of the world and from academic organisations, individual companies and consortia. Although a number of these studies have culminated in "production trials", these have invariably been on a limited scale and they were essentially a demonstration, rather than the first step to implementation....

Publisher: Multicore Solders

Low Force Placement Solution For Delicate and Low IO Flip Chip Assemblies

Jun 27, 2007 | Jason Higgins - Universal Instruments Corporation, Robert Hemann - Medtronic Microelectronics Center.

Traditionally most flip chips were designed with large bumps on a coarse pitch. However, as the trend towards smaller, more compact assemblies continues the sizes of semiconductor packages are forced to stay in line. New designs are incorporating smaller bump diameters on increasingly aggressive pitches, and in many cases decreasing the total IO count. With fewer and smaller bumps to distribute the load of the placement force it is becoming increasingly vital for equipment manufacturers to meet the challenge in offering low force placement solutions. One such solution will be presented in the following discussion. Also presented will be ways to minimize the initial impact spike that flip chips experience upon placement....

Publisher: Universal Instruments Corporation

Selective Solder Paste Deposition Reliability Test Results.

Jun 21, 2007 | Bob Wettermann.

The rapid assimilation of Ball Grid Array (BGA) and other Area Array Package technology in the electronics industry is due to the fact that this package type allows for a greater I/O count in a smaller area while maintaining a pitch that allows for ease of manufacture (...) While there have been several studies comparing these two attachment methods, this study highlights the effect of rework technique on the electrical characteristics and reliability of reworked BGAs....

Publisher: BEST Inc.

Large Thin Organic PTFE Substrates for Multichip Applications

Jun 13, 2007 | Ron Nowak, Paul Hart, Dave Alcoe.

Very high performance computer applications have created a demand for large organic substrates capable of interconnecting one or a few ASIC semiconductor devices with packaged memory devices. The electrical advantages offered by the use of a thin PTFE composite substrate were coupled with intrinsic mechanical advantages to create very high performance applications. The application development required interactions of design, fabrication, and new manufacturing technology to obtain rapid prototype production and allow a successful ensuing manufacturing ramp....

Publisher: i3 Electronics

Proof is in the PTH - Assuring Via Reliability from Chip Carriers to Thick Printed Wiring Boards

Jun 06, 2007 | Kevin T. Knadle, Virendra R. Jadhav.

Though today's microvias and high aspect plated through holes (PTH's) look nothing like the earliest through holes of 40 years ago, the PTH in its various forms remains the “weak link” and most critical element of printed wiring boards and laminate chip carriers (...) The paper outlines an approach to evaluating PTH reliability and quality that involves characterizing PTH life across a range of temperatures to reveal intricacies not seen by testing at a single delta-T, and certainly difficult to predict by modeling alone....

Publisher: i3 Electronics

Lead-free and Tin-lead Assembly and Reliability of Fine-pitch Wafer-Level CSPs

May 31, 2007 | Michael Meilunas, Muffadal Mukadam, Peter Borgesen, Hari Srihari

This paper discusses solder paste printing and flux dipping assembly processes for 0.4 and 0.5mm pitch lead-free WLCSPs and the corresponding assembly results and thermal cyclic reliability obtained. Variables evaluated include reflow ambient, paste type, and stencil design. Reliability is also compared to results for the same components assembled under identical conditions using SnPb solder....

Publisher: Universal Instruments Corporation

Phase Convection™: The Lead-Free Solution

May 30, 2007 | Jean-Jack Boumendil, Pascal Preti.

Transition to lead-free is accelerating and when considering constraints related to lead-free and conventional solder pastes, one concern is rising: flexibility. It would be dangerous to commit to lead-free only while the technology is not yet stabilized. Manufacturers need to consider all of the issues related to lead-free and need to find flexible equipment which are able to adapt to both conventional and lead-free constraints....

Publisher: Vi TECHNOLOGY

Manufacturers at the Crossroads: ERP or Best-of-Breed Software?

May 17, 2007 | Zontec, Inc

In the quest for quality, selecting the right Statistical Process Control (SPC) Software system doesn't boil down to a simple functional "fit-to-requirements" anymore. Once the expert domain of highly focused, independent software developers, the competitive landscape has changed dramatically with the influx of big-name ERP software providers who are aggressively promoting integrated quality modules within an all-encompassing business application framework....

Publisher: Zontec, Inc.

The Proximity of Microvias to PTHs And Its Impact On The Reliability

May 09, 2007 | Anthony Primavera Manager - CSP Consortium Universal Instruments Corporation, Jaydutt Joshi, Package Development Engineer - Conexant Systems Inc.

High Density Interconnect (HDI) technology is fast becoming the enabling technology for the next generation of small portable electronic communication devices. These methods employ many different dielectrics and via fabrication technologies. In this research, the effect of the proximity of microvias to Plated Through Holes (PTHs) and its effect on the reliability of the microvias was extensively evaluated. The reliability of microvia interconnect structures was evaluated using Liquid-To-Liquid Thermal Shock (LLTS) testing (-55oC to +125oC). Comprehensive failure analysis was performed on microvias fabricated using different via fabrication technologies....

Publisher: Universal Instruments Corporation

A Study of Lead-Free Wave Soldering

May 02, 2007 | David Suraski.

This brief study of lead-free wave soldering focuses upon copper dissolution and solder maintenance issues. Unfortunately, it is determined that waste and changeover costs can dramatically increase with lead-free wave soldering....

Publisher: AIM Solder

Real-Time Yield Monitoring Through ERP Systems

Apr 25, 2007 | P. Bhargava, J. Sturek, J. Peck, R. Murcko, K. Srihari

Globalization and increased competition requires an enterprise to focus on cost reduction, improved manufacturing processes and higher standards of quality. Effective yield management using Enterprise Resource Planning (ERP) systems is crucial for the success of any manufacturing organization. An ERP system provides the infrastructure for consolidating all business operations by integrating the information flow across functions, including production planning and control....

Publisher: i3 Electronics

Fragility of Pb-free Solder Joints

Apr 18, 2007 | Universal Instruments Corporation

Recent investigations have revealed that Pb-free solder joints may be fragile, prone to premature interfacial failure particularly under shock loading, as initially formed or tend to become so under moderate thermal aging. Depending on the solder pad surface finish, different mechanisms are clearly involved, but none of the commonly used surface finishes appear to be consistently immune to embrittlement processes. This is of obvious concern for products facing relatively high operating temperatures for protracted times and/or mechanical shock or strong vibrations in service....

Publisher: Universal Instruments Corporation

A Case Study in Troubleshooting Shop Floor Rework Difficulties

Apr 05, 2007 | Martin Hogner; Martin Rework and Dispense Technic, Wessling/Munich, Germany, and Allen Sirois; Web Administrator, Manncorp Inc., USA.

Recently a large global player approached us with a problem. They needed an initial assembly solution for brand new components. Their boards and CSP specimens could not safely be soldered due to wetting problems at the solder joints....

Publisher: MARTIN (a Finetech company)

Effects of Assebly Process Variables on Voiding at a Thermal Interface.

Apr 04, 2007 | Muffadal Mukadam, Jeff Schake, Peter Borgesen, Krishnaswami Srihari.

The present work offers a discussion and a first case study to identify and illustrate voiding mechanisms for a particular TIM between a heat spreader and the back of a flip chip. Pronounced differences were observed between stencil printing and dispensing in terms of initial void formation, apparently related to the specific properties of the material. Measurements of the effects of heat ramp rate and peak temperature showed the subsequent evolution and final void size distribution to be determined by the initial part of the cure profile up to the material gelling temperature....

Publisher: Universal Instruments Corporation

Lead-free Rework Process For Chip Scale Packages

Mar 28, 2007 | Arun Gowda and K. Srihari, Ph.D. - Electronics Manufacturing Research and Services, Anthony Primavera, Ph.D. Consortium Manager - Universal Instruments Corporation

Legislation against the use of lead in electronics has been the driving force behind the use of lead-free solders, surface finishes, and component lead finishes. The major concern in using lead-free solders in the assembly and rework Chip Scale Packages (CSPs) is the relatively high temperatures that the components and the boards experience. Fine-pitch CSPs have very low standoff heights following assembly making inspection and rework of these components more difficult. One other concern pertinent to rework is the temperature of the neighboring components during rework. These issues, coupled with the limitations of rework equipment to handle lead-free reflow temperatures, make the task of reworking lead-free assemblies more challenging....

Publisher: Universal Instruments Corporation

Are You Becoming E-Wasted?

Mar 13, 2007 | Jim Usery

This article gives an explanation of what e-waste is and states the regulations on how it can be disposed of. It also tells what some companies are doing to help the consumer get rid of it....

Publisher: Innovative Circuits Inc.

Prototyping Your New Electronic Product Idea

Mar 13, 2007 | Jim Usery, Sales and Marketing Director, Innovative Circuits Inc.

This article outlines the minimum tasks needed to send your new electronic product idea out for prototyping. It lists and defines the minimums to either perform your self or to have subcontracted....

Publisher: Innovative Circuits Inc.

I Have an Idea for a New Product, but Now What?

Mar 13, 2007 | Jim Usery

Do you have an idea for an electronic product, the next must-have gadget, music or video system, time saver, or the greatest problem-solving device that was ever invented? Before you begin designing the product, there are a number of tasks that you must complete and issues that you must resolve before you have an actual product design that can be produced, marketed, and sold. This article will provide you with some guidelines to assist you in getting your idea turned into a successful design. Other issues, such as whether or not to apply for a patent for your product idea and in detail how a particular product should be advertised or marketed will not be addressed in this article....

Publisher: Innovative Circuits Inc.

Basics of Manufacturing Printed Circuit Boards

Mar 13, 2007 | Jim Usery, Sales and Marketing Director, Innovative Circuits Inc.

This article tells about the basics of manufacturing printed circuit boards including the terminology and the steps to processing a PCB....

Publisher: Innovative Circuits Inc.

What Your Electronic Manufacturing Service Provider Needs from You

Mar 13, 2007 | Jim Usery, Sales and Marketing Director, Innovative Circuits Inc.

This article tells what your electronic manufacturing service providers needs from you to prepare an accurate quotation for a typical printed circuit board assembly project....

Publisher: Innovative Circuits Inc.

What Are Gerber Files for Printed Circuit Boards, and Who Needs Them?

Mar 13, 2007 | Jim Usery

This article tells what a gerber file is and what it is used for in the electronic manufacturing industry....

Publisher: Innovative Circuits Inc.

Effect of Reflow Profile on SnPb and SnAgCu Solder Joint Shear Force

Mar 08, 2007 | Jianbiao Pan, Brian J. Toleno, Tzu-Chien Chou, Wesley J. Dee

Reflow profile has significant impact on solder joint performance because it influences wetting and microstructure of the solder joint. The degree of wetting, the microstructure (in particular the intermetallic layer), and the inherent strength of the solder all factor into the reliability of the solder joint. This paper presents experimental results on the effect of reflow profile on both 63%Sn 37%Pb (SnPb) and 96.5%Sn 3.0%Ag 0.5%Cu (SAC 305) solder joint shear force....

Publisher: Henkel Electronic Materials

New BGA Solder Mask Repair Technique Using Laser Cut Stencils

Feb 01, 2007 | Ronald D. Schaeffer, Chief Executive Officer, Photomachining.

The increased replacement of high lead count SMT devices with BGAs and other high ball count area array packages has brought increased challenges to PCB rework and repair. Often solder mask areas surrounding BGA pad areas are damaged when components are removed....

Publisher: BEST Inc.

BGA Rework. A Comparative Study of Selective Solder Paste Deposition For Area Array Packages

Feb 01, 2007 | Ray Cirimele, Best, Inc

The rapid assimilation of Ball Grid Array (BGA) and other Area Array Package technology in the electronics industry is due to the fact that this package type allows for a greater I/O count in a smaller area while maintaining a pitch that allows for ease of manufacture....

Publisher: BEST Inc.

Surface Insulation Resistance (SIR) Testing

Feb 01, 2007 | Roy Johnson, Senior Staff Engineer AG Communication Systems.

Purpose: Compare the Surface Insulation Resistance of reworked BGA Test samples made with standard solder balls using a flux only reattachment and samples made including the StencilQuik™ product from Best Inc. with solder balls using a flux only reattachment....

Publisher: BEST Inc.

BGA Thermal Shock Testing

Feb 01, 2007 | Roy Johnson Senior Staff Engineer AG Communication Systems.

The purpose of the testing was to compare the resistance and check for open circuit conditions of reworked BGA test samples made with and without StencilQuik™ after 500 thermal shock cycles. StencilQuick™ is a product of Best Inc. In this series of tests, the resistance of daisy chain resistance patterns running between the BGA and test board after exposure to thermal shock was measured....

Publisher: BEST Inc.

StencilQuick™ Lead-Free Solder Paste Rework Study

Jan 31, 2007 | Ray Cirimele, BEST Inc

The goal of this project is to evaluate the reliability of lead-free BGA solder joints with a variety of different pad sizes using several different BGA rework methods. These methods included BGAs reworked with both flux only and solder paste attachment techniques and with or without the use of the BEST stay in place StencilQuick™. The daisy chained test boards were placed into a thermal test chamber and cycled between -25ºC to 125ºC over a 30 minute cycle with a 30 minute dwell on each end of the cycle. Each BGA on the board was wired and the continuity assessed during the 1000 cycles the test samples were in the chamber. ...

Publisher: BEST Inc.

Reflow Profiling Guide

Jan 31, 2007 | John Viviari, EFD, Inc.

This paper explains the solder paste reflow process and the best practices to follow when developing your profile....

Publisher: Nordson EFD

Auger Valve Dispensing

Jan 31, 2007 | John Viviari, EFD, Inc.

This white paper is suitable for both new and experienced users. It is a practical education in the use and misuse of auger valves for solder paste dispensing....

Publisher: Nordson EFD

Air Powered Dispensing

Jan 31, 2007 | John Viviari, EFD, Inc.

Air-powered dispensing systems use controlled pulses of air pressure to dispense solder paste from syringe reservoirs in uniform amounts. In this paper, EFD explains the most critical variables affecting air-powered dispensing of solder pastes and shows how to manage those variables to your advantage....

Publisher: Nordson EFD

HASL - What a Hassle, or Hasl'd Again

Jan 24, 2007 | Earl Moon

This article updates one I wrote for Printed Circuit Fabrication Magazine in December 1991. Actually, this article trashes that - and about time. I was much too kind then talking about how to control the HASL process....

Breakthrough in Molecular Design Could Unleash the Full Speed of the Internet

Jan 17, 2007 | Cherie Winner, WSU News Service

Researchers at Washington State University have created design guidelines for new molecules that could enhance the speed of internet communications and other optical technologies....

Publisher: Washington State Magazine

Printed Circuit Board Failure Analysis

Jan 10, 2007 | Earl Moon

As with all other F/A processes, PCB's occasionally need a little help from them. The following, just as the component process in Section previous, has been condensed from so many involvements over the past 35 years, I cannot remember - nor should I because they all could have been prevented with DFM/CE. However, the information presented, coupled with good DFM/CE and PCB process management provides an insight to the beast....

Dispensing Solder Paste Micro-Deposits to 0.2mm - A Process Solution

Jan 03, 2007 | John Vivari / EFD Inc.

Solder paste dispensing is not a new process. However, today's microelectronics present a daunting array of technical challenges to meet deposit size requirements. The need for better paste formulations, more precise equipment, and more tightly controlled processes is driving paste suppliers and equipment suppliers to develop new methods and materials. The most challenging solder paste deposits are those smaller than 0.25mm in diameter and today’s electronics demand such deposits. This paper addresses the process requirements for solder paste micro-deposits in terms of material, equipment and process variable control required for success in producing 0.25mm and smaller deposits....

Publisher: Nordson EFD

First Principles of Solder Reflow

Dec 18, 2006 | John Vivari / EFD Inc.

Many solder users have preconceived notions and worries involving reflow profiling guidelines. Year after year of reading profiling recommendations in industry publications, from a litany of pundits, has made it clear that perfect profiles exist and should be sought after. They feel if the solder supplier gives them a tidy drawing on a piece of paper with times and temperatures that it will magically solve all their reflow problems. This is, unfortunately, an often incorrect assumption....

Publisher: Nordson EFD

"High Reliability Products" What does it really take - A Test Perspective

Dec 04, 2006 | Subahu D. Desai

This paper will explore how test can be an integral part of manufacturing to assure High Reliability Products. We will discuss how test parameters and test techniques are effective in finding time zero vs. time dependent defects. Understanding of manufacturing processes in terms defect levels as well as defect types is very critical in defining test parameters, new test techniques and test alternatives. This ultimately can improve the yield, quality, and reliability. We will discuss the types of defects, time zero vs. time dependent defects, test parameters and effectiveness and new test techniques to find time dependent defects....

Publisher: i3 Electronics

Organic Flip Chip Packages for Use in Military and Aerospace Applications

Nov 14, 2006 | David Alcoe, Kim Blackwell and Irving Memis, Endicott NY

Content: 1. Bridge from Commercial Reliability 2. Existing PBGA use in Aerospace & Military 3. Drivers: Plastic versus Ceramic Package Weight 4. Attributes of PTFE and Thin Core FC Packages 5. Flip Chip Package Reliability 6. Flip Chip Package ...

Publisher: i3 Electronics

Improvement of Organic Packaging Thermal Cycle Performance Measurement

Nov 01, 2006 | Glenn O. Dearing, Paul J. Hart

Flip Chip Plastic Ball Grid Array (FCPBGA) modules, when subjected to extreme environmental stress testing, may often reveal mechanical and electrical failure mechanisms which may not project to the field application environment. One such test can be the Deep Thermal Cycle (DTC) environmental stress which cycles from -55°C to 125°C. This “hammer” test provides the customer with a level of security for robustness, but does not typically represent conditions which a module is likely to experience during normal handling and operation....

Publisher: IBM Corporation

Tombstone Troubleshooting

Oct 26, 2006 | Michael Forti, Applications/Process Engineer, EFD

There have been many studies of the causes of tombstoning; some published, some not. They tend to focus on a single process parameter as the root cause of tombstoning. However, there is no single process change that is a sure cure for tombstoning! Those that claim otherwise are either uninformed or trying to sell you something. Rather than limiting your view to a single solution, EFD recommends you heed all of the studies. Like pieces of a puzzle, each study does not reveal the whole picture, but looked at all together, the picture is clear....

Publisher: Nordson EFD

Assembly And Reliability Issues Associated With Leadless Chip Scale Packages

Oct 02, 2006 | Michael Meilunas of Universal Instruments Corporation, Binghamton, NY; Muffadal Mukadam, and Hari Srihari of Binghamton University, Binghamton, NY

This paper addresses the assembly and reliability of 0.5 mm pitch leadless Chip Scale Packages (CSP) on .062" immersion Ag plated printed circuit boards (PCB) using Pb-free solder paste. Four different leadless CSP designs were studied and each was evaluated using multiple PCB attachment pad designs....

Publisher: Universal Instruments Corporation

Evaluating Soldering Irons for Lead Free Assembly -A Quantitative Approach

Sep 06, 2006 | Purnanand G. Samant, Srikanth Poranki, & Daryl Santos, Ph.D,

Transition to lead free solder stations in electronics packaging has raised issues regarding process, metallurgy and reliability m assemblies. In regards to soldering, lead has been used for thousands of years in a wide range of applications. Conventional eutectic or near eutectic tin-lead solder compositions have been used for virtually all soldering applications in electronics assembly for the last 50 years, In the electronics assembly process, a majority of commercial rework applications and some low density board assembly processes require hand soldering stations (...) This paper describes an attempt to quantify both qualitative and quantitative data that can aid in the evaluation of lead free soldering irons....

Publisher: T.J. Watson School of Engineering and Applied Science

Design For Test Considerations For PCB Design

Jul 14, 2006 | Zulki Khan, president and founder, Nexlogic, Inc.

The perennial question in electronics design and manufacture is: "How do I design a printed circuit board (PCB) so that it can be properly tested?" To achieve this objective, there are a number of design-for-test (DFT) considerations and techniques. Some are major, others, minor. However, the total contributes to a highly effective PCB design so that testing procedures applied to a given design result in high 90 percent plus test coverage....

Publisher: NexLogic Tech, Inc.

Testing To Eliminate Reliability Defects From Electronic Packages

Jun 29, 2006 | Irving Memis, Consultant, Endicott Interconnect Technologies

Electronic Packaging is a critical part of all electronic devices and can be a source of the reliability problems experienced by systems using those devices. In many cases, the packaging defects are intermittent in nature and difficult to detect. This paper describes a tester that has been used for 20 years on commercial products and has proven to be extremely effective in detecting these defects prior to component assembly....

Publisher: i3 Electronics

Wave Solder Parameter Chart

May 13, 2006 | Kantesh Doss

This Excel Spreadsheet calculates the Wave Solder Contact Time automatically with given main Solder Wave width and Conveyor Speed. There is one chart where conveyor speed is expressed in meters/min and in another where it is expressed in feet/minute....

Publisher: Jabil Circuit, Inc.

You, too, can do 0402!

May 16, 2005 | Bill Shaw, Articulation LLC

Low cost techniques for building prototype and low volume SMT printed circuit boards....

Publisher: Articulation LLC

No-Residue Technology Chemistry and Physics

Sep 02, 2004 | Patrick O. Bruneel Technical Advisor - Interflux USA, Inc.

The main goal of this paper is to highlight the importance of interrelating the physics and the chemistry in wave soldering and soft soldering in general. Often we find the disciplines of chemistry and physics being analyzed distinct and separate. However in the quest for alternative ways for leading edge competitive and especially environmental friendly manufacturing, separating or ignoring this interrelationship is detrimental to the success of No-Residue soldering....

Publisher: Interflux USA, Inc.

Cost Analysis of Printed Circuit Boards

May 23, 2004 | By Gold Phoenix's North America Service and Tech Center

This is an article written by our company's experts to help our customers to make informed decision on PC boards purchasing. It introduces the materials that are used in the PCB manufacturing and the cost analysis of different materials....

Publisher: Gold Phoenix PCB Co, Ltd

0201 Placement - Only With The Right Team and Tools!

Sep 17, 2003 | P.Gerits / A.Mandos

It appears very logical that the successor of the 0402 size SMD would be the 0201. Curves showing the life-cycle of a body size, from introduction to most used to only for special cases, are very similar for the 1206, 0805, 0603 and 0402. So there is reason to expect that the same will happen with the 0201. Until now there is only little evidence for this, but most technologies come later than expected but faster than expected!...

Publisher: Assembléon