Jan 24, 2008 | Gerjan Diepstraten, Senior Process Engineer, Vitronics Soltec BV
The wave solder process is characterized by a large number of process parameters. To understand them all and their interactions is challenging, particularly when it comes to lead-free soldering. Wave soldering has a number of sub-processes, which include fluxing, preheating, soldering and cooling....
Publisher: Vitronics Soltec
Jan 16, 2008 | Dr. Daryl Santos, SUNY Binghamton; Dr. Rita Mohanty, Speedline Technologies
The consumer's interest for smaller, lighter and higher performance electronics products has increased the use of ultra fine pitch packages, such as Flip Chips and Chip Scale Packages, in printed circuit board (PCB) assembly. The assembly processes for these ultra fine pitch packages are extremely complex and each step in the assembly process influences the assembly yield and reliability....
Publisher: Speedline Technologies, Inc.
Speedline Technologies serves the electronics assembly and semiconductor packaging industries with class-leading equipment, responsive support and unparalleled process knowledge.
Franklin, Massachusetts, United States
Jan 10, 2008 | Denis Barbini, Vitronics Soltec; Paul Wang, Microsoft; Peter Biocca, ITW Kester; Quyen Chu, Jabil
This research takes an in-depth look at the challenges encountered in developing a lead free wave soldering process based on the specific products as well as on specific materials. It attempts to provide the reader with the information necessary to make educated decisions in selecting materials and controlling various process parameters in order to execute a rational implementation strategy for a reliable and robust lead free wave soldering process....
Publisher: Vitronics Soltec
Jan 03, 2008 | Peter Biocca, Senior Development Engineer, Kester.
Lead-free SMT can be achieved reliably if several process requirements are implemented carefully. Some of the variables to account for are listed below. The most common alloys used in lead-free SMT are tin-silver-copper alloys; these alloys all have a meting range between 217- 220°C. These alloys all melt at higher temperatures than traditional leaded solders such as the 63/37which has a melting point of 183 °C....
Dec 27, 2007 | DEK
The latest screen printing platforms unlock more of the potential from dual-lane processing. Simultaneous demands to enhance flexibility while increasing utilisation and overall throughput apply to manufacturers operating at virtually any point in the mix-volume continuum: capacity must work hard to deliver the required return. As these lean manufacturing principles hold sway from the US and Europe to the Far East, no modern assembler has a second to spare....
Publisher: DEK International
Dec 20, 2007 | David Suraski
Despite much research and discussion on the subject of reflow profiling, many questions and a good deal of confusion still exist. What is clear is that the pains often associated with profiling can be reduced if there is a strong understanding of the variables that can be encountered during the reflow process, as well as the metallurgical dynamics of the soldering process. This paper shall provide a brief outline of the reflow profile in general, with specific emphasis placed upon the suggested time spent above the melting temperature of the solder. The guidelines for soldering to various surfaces and with alternative solder alloys also are discussed....
Publisher: AIM Solder
Dec 13, 2007 | Steve Watkin, Semicon Packaging Technologies Division, and Tom Falcon, Future Technologies Group, DEK
Printer-hosted processes for solder ball placement are now widely used for package technologies ranging from BGAs using ball diameters above 750μm to the latest WL-CSPs demanding 250μm diameter. This broadening spectrum of applications brings more choices in terms of stencil design rules and production methodologies....
Publisher: DEK International
Dec 06, 2007 | Fred Dimock, Kristen Mattson.
Over the past 30 years we have learned that lead has negative affects on the health of humans and seen strong legislation remove it from gasoline and paints. More recently, governments in Europe and Asia have set deadlines to remove lead from consumer electronic devices that use printed circuit boards. Currently, the ban is not being applied to high reliability applications such as military or medical devices, but we all know that will come someday soon. Likewise many believe that lead free solder is coming to wafer bump reflow and are beginning to make the transition....
Publisher: BTU International
Nov 29, 2007 | Pericles Kondos, Peter Borgesen, Dan Blass, and Antonio Prats.
Programs have been developed to predict the expected yield of flip chip assemblies, based on substrate design and the statistics of actual manufactured boards, as well as placement machine accuracy, variations in bump sizes, and possible substrate warpage. These predictions and the trends they reveal can be used to direct changes in design so that defect levels will fall below the acceptable limits. Shapes of joints are calculated analytically, or when this is not possible, numerically by means of a public domain program called Surface Evolver. The method is illustrated with an example involving the substrate for a flip chip BGA....
Publisher: Universal Instruments Corporation
Provider of circuit, semiconductor, back-end assembly technologies and equipment, as well as integrated system solutions to manufacturers in various sectors of the electronics industry.
Conklin, New York, United States
Nov 21, 2007 | Rabindra N. Das, Frank D. Egitto, John M. Lauffer and Voya R. Markovich.
This paper discusses laser micromachining of barium titanate (BaTiO3)-polymer nanocomposites and sol-gel thin films. In particular, recent developments on high capacitance, large area, and thin flexible embedded capacitors are highlighted....
Publisher: i3 Electronics
A world leader in high-performance PCB fabrication & assembly, semiconductor packaging, systems integration & test, advanced laboratory services and contract R&D.
Endicott, New York, United States