Technical Library | 2009-07-22 18:33:41.0
This paper deals with the thermal effects of joule heating in a high interconnect density, thin core, buildup, organic flip chip substrate. The 440 μm thick substrate consists of a 135 μm thick core with via density of about 200 μm. The typical feature sizes in the substrate are 50 micron diameter vias is the core/buildup layers and 12 micron thick metal planes. An experimental test vehicle is powered with current and the temperature rise was measured. A numerical model was used to simulate the temperature rise in the TV.
Technical Library | 2010-09-10 09:47:06.0
An optimal reflow profile is one of the most critical factors in achieving quality solder joints on a printed circuit board (PCB) assembly with surface mount components. A profile is a function of temperatures applied to the assembly over time. When graphed on a Cartesian plane, a curve is formed that represents the temperature at a specific point on the PCB, at any given time, throughout the reflow process.
Technical Library | 2014-03-20 12:37:39.0
In the beginning of SMT, Vapor Phase Soldering was the preferred reflow soldering technology because of its excellent heat transfer capabilities. There were also some disadvantages like fast temperature rise, nearly no influence on the temperature profiles and high costs. So the use of Vapor Phase Soldering was reduced to special applications with high mass or complex boards in low numbers (e.g. for military or aerospace use).
Technical Library | 2020-09-30 19:26:45.0
Introduction •Market trend: Smaller, more efficient, more powerful, run faster •ICs and other sophisticated electronic components typically operate efficiently only under a certain range of temperatures •Operational temperatures must be kept within a suitable range • Excessive heat can damage performance and can even cause system failure
Technical Library | 2017-10-16 15:03:32.0
The miniaturization and advancement of electronic devices have been the driving force of design, research and development, and manufacturing in the electronic industry. However, there are some issues occurred associated with the miniaturization, for examples, warpage and reliability issues. In order to resolve these issues, a lot of research and development have been conducted in the industry and university with the target of moderate melting temperature solder alloys such as m.p. 280°C. These moderate temperature alloys have not resolve these issues yet due to the various limitations. YINCAE has been working on research and development of the materials with lower temperature soldering for higher temperature application. To meet this demand, YINCAE has developed solder joint encapsulant paste to enhance solder joint strength resulting in improving drop and thermal cycling performance to eliminate underfilling, edge bonding or corner bonding process in the board level assembly process. This solder joint encapsulant paste can be used in typical lead-free profile and after reflow the application temperature can be up to over 300C, therefore it also eliminates red glue for double side reflow process. In this paper, we will discuss the reliability such as strength of solder joints, drop test performance and thermal cycling performance using this solder joint encapsulant paste in detail.
Technical Library | 2021-11-03 16:49:59.0
Ultrathin bare die chips were soldered using a novel soldering technology. Using homogeneous flash light generated by high-power xenon flash lamp the dummy components and the bare die NFC chips were successfully soldered to copper tracks on polyimide (PI) and polyethylene terephthalate (PET) flex foils by using industry standard Sn-Ag-Cu lead free alloys. Due to the selectivity of light absorption, a limited temperature increase was observed in the PET substrates while the chip and copper tracks were rapidly heated to a temperatures above the solder melting temperature. This allowed to successfully soldered components onto the delicate polyethylene foil substrates using lead-free alloys with liquidus temperatures above 200 °C. It was shown that by preheating components above the decomposition temperature of solder paste flux with a set of short low intensity pulses the processing window could be significantly extended compared to the process with direct illumination of chips with high intensity flash pulse. Furthermore, it was demonstrated that with localized tuning of pulse intensity components having different heat capacity could be simultaneously soldered using a single flash pulse.
Technical Library | 2011-12-22 16:45:49.0
This paper reports the feasibility of using surface mount adhesives to produce low temperature microchannel arrays in a wide variety of metals. Sheet metal embossing and chemical etching processes have been used to produce sealing bosses that eliminate ch
OSU School of Mechanical, Industrial, and Manufacturing Engineering (MIME)
Technical Library | 2012-12-20 14:36:09.0
The increased function of personal electronic devices, such as mobile phones and personal music devices, has driven the need for smaller and smaller active and passive components. This trend toward miniaturization, occurring at the same time as the conversion to RoHS-compliant lead-free assembly, has been a considerable challenge to the electronics assembly industry. The main reason for this is the higher reflow process temperatures required for Pb-free assembly. These higher temperatures can thermally damage the PCB and the components. In addition, the higher reflow temperatures can negatively affect the solder joint quality, especially when coupled with the smaller paste deposits required for these smaller components. If additional thermal processing is required, the risk increases even more. First Published at SMTA's International Conference on Soldering and Reliability in Toronto, May 2011
Technical Library | 2016-01-12 11:05:28.0
The electronic industry is currently very interested in low temperature soldering processes such as using Sn/Bi alloy to improve process yield, eliminate the head-in-pillow effect, and enhance rework yield. However, Sn/Bi alloy is not strong enough to replace lead-free (SAC) and eutectic Sn/Pb alloys in most applications. In order to improve the strength of Sn/Bi solder joints, enhance mechanical performance, and improve reliability properties such as thermal cycling performance of soldered electronic devices, YINCAE has developed a low temperature solder joint encapsulant for Sn/Bi soldering applications. This low temperature solder joint encapsulant can be dipped, dispensed, or printed. After reflow with Sn/Bi solder paste or alloy, solder joint encapsulant encapsulates the solder joint. As a result, the strength of solder joints is enhanced by several times, and thermal cycling performance is significantly improved. All details will be discussed in this paper.
Technical Library | 2016-05-13 11:44:16.0
The process of manufacturing and qualifying IC's consists of many steps while Temperature forcing systems play a crucial role in the final testing process. These environmental tests assure quality and reliability by stressing the device on one hand as well as helping to characterize and validate it on the other hand (making sure manufacturing outcome meets the design requirements). At later stages the temperature testing can support failure analysis effort and root cause analysis. AS common practice we are dealing with few different kinds of temperature forcing systems: Chambers, Thermal Stream systems and Direct Thermal Head systems. In this article I would like to focus on the practical aspects of utilizing Thermal Stream systems and Direct Thermal Head systems.
