Electronics Manufacturing Technical Articles

Nov 29, 2012

Craig T. Pynn

First published in the 2012 IPC APEX EXPO technical conference proceedings... Functional circuit test (FCT) of circuit boards and end products in a high volume (>1000 units per day) production environment presents challenging technical, logistic and cost obstacles that are usually more complex than those encountered at the inspection (automated optical inspection) and the manufacturing process test step (in-circuit test)....

Nov 21, 2012

Brian D'Amico

The continuing evolution toward advanced miniature packaging has led to ever increasing PCB density and complexity. As the manufacturing process becomes progressively more complicated, there is an ever increasing probability for defects to occur on finished PCB assemblies. For years the Automated Optical Inspection (AOI) industry has relied solely upon two-dimensional (2D) inspection principles to test the quality of workmanship on electronic assemblies. While advancements in conventional 2D optical inspection have made this technology suitable for detecting such defects as missing components, wrong components, proper component orientation, insufficient solder, and solder bridges; there is an inherent limitation in the ability to inspect for co-planarity of ultra-miniature chips, leaded device, BGA and LED packages....

Nov 15, 2012

Rajat Basu, Ryan Hulse, Kane Cook, Diana Mercier

First published in the 2012 IPC APEX EXPO technical conference proceedings. As we progress in the 21st century, electronics manufacturing will need more and more precision. Parts will get more complex since more components have to be assembled in smaller spaces. Circuit boards and other electronic assemblies will become more densely populated; spacings between components will be shorter. This will require precision manufacturing and efficient cleaning during and post manufacturing. In addition, with population and technology progressing, larger amount of greenhouse gases will be emitted resulting in higher global warming. Intense research effort is going on to develop new generation of chemicals to address both cleaning and global warming issues. Low global warming solutions in refrigeration and as insulating agents are already in the marketplace....

Nov 08, 2012

Bev Christian, Irina Romanova, Laura Turbini

first published in the 2012 IPC APEX EXPO technical conference proceedings. Twenty-nine different cells phones have been disassembled, ground up, dissolved and analyzed for elemental content, mainly for information about the metals present in the phones, but also for some metalloids and non-metals. The paper will discuss the method used and propose possible sources in the telephones for certain elements of interest and the reasons for the interest in some of the elements....

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Nov 01, 2012

Edward N. Peters, Scott M. Fisher, Hua Guo

First published in the 2012 IPC APEX EXPO technical conference proceedings. The continuous progression toward portable, high frequency microelectronic systems has placed high demands on material performance, notably low dielectric constants (Dk), low loss tangent (Df), low moisture uptake, and good thermal stability. Epoxy resins are the workhorses of the electronic industry. Significant performance enhancements have been obtained through the use of PPE telechelic macromonomers with epoxy resins. However, there is a ceiling on the performance obtainable from epoxy-based resins. Therefore, non-epoxy based dielectric materials are used to fulfill the need for higher performance....

Oct 25, 2012

William E. Coleman Ph.D.

First published in the 2012 IPC APEX EXPO technical conference proceedings. This paper will examine stencil technologies (including Laser and Electroform), Aperture Wall coatings (including Nickel-Teflon coatings and Nano-coatings), and how these parameters influence paste transfer for miniature devices with Area Ratios less than the standard recommended lower limit of .5. A matrix of print tests will be utilized to compare paste transfer and measure the effectiveness of the different stencil configurations. Area Ratios ranging from .32 to .68 will be investigated....

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Oct 23, 2012

Peter Biocca, Senior Development Engineer

Tin-Silver-Copper alloys are the primary choice for lead-free SMT assembly. Although there are other options available such as alloys containing bismuth or indium and other elements, tin-silver-copper solders, also known as SAC alloys are by far the most popular. They are used by approximately 65% of users, as last surveyed by Soldertec in 2003....

Oct 18, 2012

Julie Silk, Jianbiao Pan, Mike Powers

First published in the 2012 IPC APEX EXPO technical conference proceedings. In this paper, we report on a comprehensive study regarding the morphology evolution and voiding of SnAgCu solder joints on the central pad of two different packages – QFN and an Agilent package called TOPS – on PCBs with a Ni/Au surface finish....

Oct 11, 2012

Mustafa Özkök, Joe McGurran, Dieter Metzger, Hugh Roberts

First published in the 2012 IPC APEX EXPO technical conference proceedings. This paper shows the benefits by using a pure palladium Layer in the ENEPIG (Electroless Nickel, Electroless Palladium, Immersion Gold) and ENEP (Electroless Nickel, Electroless P...

Oct 04, 2012

M.H. Biglaria, A. Nazariana, R. Denteneera, M. Biglari, Jra, A.A. Kodentsov

First published in the 2012 IPC APEX EXPO technical conference proceedings... Due to the obsolescence of SnPb BGA components, electronics manufacturers that use SnPb solder paste either have to use lead-free BGAs and adjust the reflow process or re-ball t...

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