Technical Library | 2011-03-10 18:59:02.0
History shows that the electronics assembly industry is always up for a good challenge. This was proven with the successful move from through-hole to SMT assembly, the elimination of CFCs from the cleaning process and implementation of lead
Technical Library | 2012-01-19 19:14:49.0
The history of multilayered, three-dimensional monolithic microwave integrated circuit (3-D MMIC) technology is described here. Although significant researches were carried out in the second half of 1990’s, still there were many twists and turns before an
Technical Library | 1999-05-06 13:41:18.0
Invented in 1971, the microprocessor evolved from the inventions of the transistor (1947) and the integrated circuit (1958). Essentially a computer on a chip, it is the most advanced application of the transistor. The influence of the microprocessor today is well known, but in 1971 the effect the microprocessor would have on everyday life was a vision beyond even those who created it. This paper presents the history of the microprocessor in the context of the technology and applications that drove its continued advancements.
Technical Library | 2021-12-02 01:51:28.0
The catchphrase "Industry 4.0" is widely regarded as a methodology for succeeding in modern manufacturing. This paper provides an overview of the history, technologies and concepts of Industry 4.0. One of the biggest challenges to implementing the Industry 4.0 paradigms in manufacturing are the heterogeneity of system landscapes and integrating data from various sources, such as different suppliers and different data formats. These issues have been addressed in the semiconductor industry since the early 1980s and some solutions have become well-established standards. Hence
Technical Library | 2023-03-16 19:07:51.0
HISTORY: * In the late 1970s an abrupt unpredictable loss of insulation resistance was observed in PCBs, which were subject to hostile climatic conditions of high relative humidity and temperature while having an applied voltage. * The loss of resistance, even leading to a short circuit was observed to be due to the growth of a subsurface filament from the anode to the cathode. * The term "Conductive Anodic Filamentation" (CAF) was coined.
Technical Library | 2017-05-17 22:33:43.0
The selective soldering application requires a combination of performance attributes that traditional liquid fluxes designed for wave soldering applications cannot fulfill. First, the flux deposition on the board needs to be carefully controlled. Proper fine tuning of the flux physicochemical characteristics combined with a process optimization are mandatory to strike the right balance between solderability and reliability. However, localization of the flux residue through the drop jet process is not enough to guarantee the expected performance level. The flux needs to be designed to minimize the impact of unavoidable spreading and splashing events.From this perspective a fundamental understanding of the relationships between formulation and reliability is critical. In this application, thermal history of the flux residues (from room temperature to solder liquidus) is a key performance driver. Finally, it is necessary to conduct statistically designed experiments on industrial selective soldering machines in order to map the relationships between flux characteristics and selective process friendliness.
Technical Library | 2021-07-27 14:54:26.0
Fast forward to current time. Today, our society embraces cleanliness. We expect, demand, and evaluate cleanliness in almost every aspect of our lives. We wash our cars and pets. We maintain high cleanliness standards in our hotels and public spaces. We require cleanliness in our restaurants and hospitals. We sanitize our hands throughout the day to prevent illness. We live in a clean-centric culture. While we drive clean cars, stay in clean hotels and eat clean food, there is one part of our life where we actually abandoned cleanliness. Many of the circuit assemblies that affect almost every aspect of our daily lives are no longer required to be clean. Even though our life experience confirms the link between cleanliness and reliability, happiness, health, and safety, circuit assemblies no longer maintain that "cleanliness is next to Godliness" status. This was not always the case. There was a time when virtually all circuit assemblies were cleaned. The removal of flux and other process-related contamination was commonplace. Cleaning was as normal as soldering. As we bring history into current time, one may relate the fall of Rome and its adoption of personal hygiene and the subsequent decline in human health to the large-scale abandonment of cleanliness expectations of circuit assemblies and the subsequent reliability issues it has created. How did this happen? Has history repeated itself?
Technical Library | 2013-03-27 23:43:40.0
Vapor phase, once cast to the annals’ of history is making a comeback. Why? Reflow technology is well developed and has served the industry for many years, it is simple and it is consistent. All points are true – when dealing with the centre section of the bell curve. Today’s PCB manufacturers are faced with many designs which no longer fall into that polite category but rather test the process engineering groups with heavier and larger panels, large ground planes located in tricky places, component mass densities which are poorly distributed, ever changing Pb Free alloys and higher process temperatures. All the time the costs for the panels increase, availability of “process trial” boards diminishes and yields are expected to be extremely high with zero scrap rates. The final process in the assembly line has the capacity to secure all the value of the assembly or destroy it. If a panel is poorly soldered due to poor Oven setup or incorrect programming of the profile the recovery of the panel is at best expensive, at worst a loss. For these challenges people are turning to Vapor Phase.
Technical Library | 2016-07-28 17:00:20.0
Packaging trends enable disruptive technologies. The miniaturization of components reduces the distance between conductive paths. Cleanliness of electronic hardware based on the service exposure of electrical equipment and controls can improve the reliability and cost effectiveness of the entire system. Problems resulting from leakage currents and electrochemical migration lead to unintended power disruption and intermittent performance problems due to corrosion issues.Solvent cleaning has a long history of use for cleaning electronic hardware. Limitations with solvent based cleaning agents due to environmental effects and the ability to clean new flux designs commonly used to join miniaturized components has limited the use of solvent cleaning processes for cleaning electronic hardware. To address these limitations, new solvent cleaning agents and processes have been designed to clean highly dense electronic hardware.The research study will evaluate the cleaning and electrical performance using the IPC B-52 Test Vehicle. Lead Free noclean solder paste will be used to join the components to the test vehicle. Ion Chromatography and SIR values will be reported.
Technical Library | 2024-06-23 21:57:16.0
Two extremes of reflow time scale for copper pillar flip chip solder joints were explored in this study. Sn-2.5Ag solder capped pillars were joined to laminate substrates using either conventional forced convection reflow or the controlled impingement of a defocused infrared laser. The laser reflow joining process was accomplished with an order of magnitude reduction in time above liquidus and a similar increase in solidification cooling rate. The brief reflow time and rapid cooling of a laser impingement reflow necessarily affects all time and temperature dependent phenomena characteristic of reflowed molten solder. These include second phase precipitate dissolution, base metal (copper) dissolution, and the extent of surface wetting. This study examines the reflow dependent microstructural aspects of flip chip Sn-Ag joints on samples of two different size scales, the first with copper pillars of 70μm diameter on 120μm pitch and the second with 23μm diameter pillars on a 40μm pitch. The length scale of Pb-free solder joints is known to affect the Sn grain solidification structure; Sn grain morphology will be noted across both reflow time and joint length scales. Sn grain morphology was further found to be dependent on the extent of surface wetting when such wetting circumvented the copper diffusion barrier layer. Microstructural analysis also will include a comparison of intermetallic structures formed; including the size and number density of second phase Ag3Sn precipitates in the joint and the morphology and thickness of the interfacial intermetallics formed on the pillar and substrate surfaces.
