TITLE

Waste Not, Want Not

AUTHOR(S)
Ferry, Jeff
PUB. DATE
April 2003
SOURCE
Circuits Assembly;Apr2003, Vol. 14 Issue 4, p48
SOURCE TYPE
Trade Publication
DOC. TYPE
Article
ABSTRACT
The article presents a procedure that will simplify ball grid array (BGA) rework. Leftover solder is commonly removed from the site after rework, but prepping the pads, depositing fresh solder paste, placing the new BGA and heating the board takes time. The irregular solder pattern may result in opens or shorts with the replacement BGA and could cause irregular balls. Even performing the same operation on the same site on the same circuit assembly type in succession may expose the assembly to unexpected thermal variation, since the rework machine can build up residual heat and experience voltage of airflow variation.
ACCESSION #
9527936

 

Related Articles

  • Factors Influencing Tombstoning. Singh, Parminder // Circuits Assembly;Apr2005, Vol. 16 Issue 4, p36 

    This article informs that as component size decreases from 0603 to 0402, 0201 and even 01005, solder paste surface tension has catastrophic effect. Surface tension forces acting on two sides of the pads, if not balanced by component weight, can lift components from the circuit board. The defect...

  • BGA Repair for Mixed Assemblies.  // Circuits Assembly;May2006, Vol. 17 Issue 5, p54 

    This article provides information on ball grid array (BGA) repair for mixed assemblies. BGA devices are especially sensitive to mixed solders in the rework process. Studies of BGA assembled with mixed solder technologies show successes and some areas of concern. The biggest problem arises when...

  • Solder charge - the alternative to BGA. Endres, Herbert // Electronics Weekly;10/22/2008, Issue 2357, p20 

    The article focuses on the use of solder charge instead of ball grid array (BGA) to meet the demands of high density mezzanine connector market. BGA had some drawbacks in it including solder wicking during reflow, missing connections and coplanarity. In the solder charge concept, a blanked...

  • Electrical resistance of Sn-Ag-Cu ball grid array packages with Sn-Zn-Bi addition jointed at 240 °C. Po-Cheng Shih; Kwang-Lung Lin // Journal of Materials Research;Jan2007, Vol. 22 Issue 1, p2 

    Sn-8Zn-3Bi solder paste and Sn-3.2Ag-0.5Cu solder balls were reflowed simultaneously at 240 °C on Cu/Ni/Au metallized ball grid array substrates. The joints without Sn-Zn-Bi addition (only Sn-Ag-Cu) were studied as a control system. Electrical resistance was measured after multiple reflows...

  • Lead-free Solder Paste.  // SMT: Surface Mount Technology;Apr2006, Vol. 20 Issue 4, p45 

    The article features Multicore LF328 from Henkel Corp. It is a halide-free, no-clean, lead-free solder paste designed for high-volume stencil printing applications with CSP lead pitches of 0.5 and 0.4 mm. The formula is reported to provide low voiding in Ball Grid Array joints over a range of...

  • A Fixture for Characterizing Underfill. Clifford, Tom // Circuits Assembly;May2006, Vol. 17 Issue 5, p52 

    This article focuses on underfill characterization in electronics manufacturing. Underfill can improve the reliability of ball grid array technology during exposure to thermal cycle or vibration. The development of the best material and processing is often hampered by visibility. Flow fronts,...

  • Methodology for Analyzing Slip Behavior in Ball Grid Array Lead-Free Solder Joints After Simple Shear. Bite Zhou; Bieler, Thomas R.; Tae-Kyu Lee; Kuo-Chuan Liu // Journal of Electronic Materials;Dec2009, Vol. 38 Issue 12, p2702 

    To examine how a lead-free solder joint deforms requires understanding of both the elastic and plastic stress and strain behavior. While elastic properties are extremely anisotropic, as discussed in a companion paper, plastic response is also anisotropic, and depends on crystal orientation and...

  • Evaluations of Whisker Growth and Fatigue Reliability of Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.05Ce Solder Ball Grid Array Packages. Tung-Han Chuang; Chih-Yuan Cheng; Tao-Chih Chang // Journal of Electronic Materials;Dec2009, Vol. 38 Issue 12, p2762 

    Sn-Ag-Cu solders doped with rare-earth elements were reported to exhibit beneficial mechanical properties; however, rapid whisker growth could be induced. In order to retain the advantageous effects of rare-earth doping without causing the formation of tin whiskers, a Sn-3Ag-0.5Cu-0.05Ce alloy...

  • When to Use Underfill with BGAs.  // Circuits Assembly;Feb2007, Vol. 18 Issue 2, p90 

    The article focuses on the use of underfill materials with ball grid arrays (BGA). A BGA or flip chip will expand or contract differently when exposed to thermal cycling. This creates a stress on the device solder connection and underfill is used as a stress reliever. Under the Electronics...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics