Jul 09, 2009 | Steve Stach.
Sometimes you just cannot clean with water. Good examples of this are: circuits with batteries attached, cleaning prior to encapsulation, ionic cleanliness testing, and non-sealed or other water sensitive parts. High impedance or high voltage circuits need to be cleaned of flux residues and other soils to maximize performance and reliability and, in these types of circuits; water can be just as detrimental as fluxes. When solvent cleaning is called for, Hansen solubility parameters can help target the best solvent or solvent blend to remove the residue of interest, and prevent degradation of the assembly being manufactured. In short, using this approach can time, manufacturing cost and reduce product liability....
Publisher: Austin American Technology
Jul 01, 2009 | Steve Stach, Austin American Technology Harald Wack, Ph.D., Umut Tosun, Naveen Ravindran, ZESTRON America, John M. Radman, Daniel D. Phillips, Trace Laboratories East
During the last 5 years, the processes to remove flux residues especially for lead-free and challenging geometries have demonstrated new cleaning obstacles which have to be overcome.i A new methodology has been recently developed to further increase the propensity for successful cleaning.ii At the core of this method is the thermal identification of the residue matrix. Thermal energy changes the physical state, i.e. transitions between liquid, solid and gas phases. By taking advantage of such specific information during phase transitions, the cleaning process can be tailored to such settings, which in turn increases the cleaning success significantly....
Publisher: ZESTRON Corporation
Jun 25, 2009 | George Babka, Scott Zerkle; Assembléon Americas, Frank Andres, Rahul Raut, Westin Bent; Cookson Electronics Assembly Materials, Dave Connell; Research in Motion.
Although blade contact angle is a critical stencil printing parameter, screen printers have so far been unable to vary it "on-the-fly", in software. The recently released Assembléon/Yamaha YGP printer has changed this, and has made new application research possible to study a crucial 01005 process variable for feature printing that previous researchers have ignored.
We have designed the first robust solder paste printing process for 01005 components that uses only a single printer and stencil. We have studied transfer efficiencies across all the major parameters, with important results for reliable high-density equipment assembly. Our findings show that a variable blade contact angle can print fine features with wider process window, and reduce overall process variation between boards produced from a line....
Jun 17, 2009 | Karl Seelig, Michael Burgess.
The increased interest in halogen-free assemblies is a result of Non-Government Organizations (NGOs) exerting pressure on electronic equipment manufacturers to eliminate halogens. The NGOs primary focus is on resolving global environmental issues and concerns. As a result of an increase in the enormous "e-waste" dump sites that have begun showing up around the world, NGOs are pushing consumer electronic manufacturers to ban halogen-containing material in order to produce "green" products. Not only are these sites enormous, but the recycling methods are archaic and sometimes even illegal.
This stockpiling and dumping has created growing political and environmental issues. In order to deal with this issue, the question of why halogens are a focal point must be addressed....
Publisher: AIM Solder
Jun 11, 2009 | Ranjit S Pandher, Brian G Lewis, Raghasudha Vangaveti, Bawa Singh
The shock reliability of solder joints has become a major issue for the electronic industry partly because of the ever increasing popularity of portable electronics and partly due the transition to lead free solders....
Publisher: Cookson Electronics
Jun 11, 2009 | Cree, Inc.
XLamp LEDs lead the solid-state lighting industry in brightness while providing a reflow-solderable design that is optimized for ease of use and thermal management. Lighting applications featuring XLamp LEDs maximize light output and increase design flexibility, while minimizing environmental impact. This application note serves as a guide to understanding thermal management of XLamp LEDs and minimizing the effects of elevated junction temperatures....
Publisher: Cree, Inc.
Jun 02, 2009 | Matti Niskala, Product Manager; Evox Rifa Group Oyj, a KEMET Company.
Today the lead free soldering process is a must in commercial electronics and it is also coming more and more important in automative and industrial electronics sectors in the near future. The most common choices for lead free solders are different Tin-Solder-Copper (SAC) alloys. Processes using SAC solders cause extra stress, because of increased process temperatures, especially to the plastic materials....
Publisher: KEMET Electronics Corporation
May 28, 2009 | Stuart Erickson, President; Ultrasonic Systems, Inc.
Considerable effort is ongoing to improve the efficiency and to move towards high-volume manufacturing of photovoltaic cells. Much attention has been focused on developing in-line processes to replace the current batch processes. A critical process to improve the performance of solar wafers is the application of Dopants. The basic requirement for this process is an automated method for applying a very thin, uniform film of Dopant to the silicon wafer as part of an in-line manufacturing process....
Publisher: Ultrasonic Systems, Inc.
May 21, 2009 | John Prymak, Corey Antoniades, Peter Blais, Allen Hill, Ken Lai, Mark Laps, Kevin Lynn, Reggie Phillips, Corey Riedl, Axel Schmidt, Bill Sloka, Paul Staubli; KEMET Corporation.
Failure due to board flex cracks persists as the dominant failure mode in multi-layer ceramic capacitors (MLCC). (...) This paper is intended to show the impact of temperature cycling, high-temperature life tests, and multiple bend exposures to the MLCC with this flexible termination....
Publisher: KEMET Electronics Corporation
May 14, 2009 | MYDATA automation
Is screen printing technology able to keep pace with rising quality demands and increasingly complex board layouts? Or, is new jet printing technology ready to fill the gap? A comparison study between the two methods reveals some interesting differences. Screen printers offer some possibilities for optimizing solder paste deposits, but optimization is far easier and quicker with the jet printer. At the same time, the ability to print individualized deposits on every single pcb pad may be the ultimate answer to the growing quality challenge....
Publisher: Mycronic Technologies AB