Technical Library | 2013-12-05 17:09:03.0
The functionality of electronic devices continues to increase at an extraordinary rate. Simultaneously consumers are expecting even more and in ever smaller packages. One enabler for shrinking electronics has been the flexible circuit board that allows the circuit board to fit a wide variety of shapes. Flexible printed circuits (FPC) have the capability to be very thin and can have unpackaged components directly attached using surface mount technology (SMT) and flip chip on flex technologies. Bare die can also be thinned and attached very close to the circuit board. However one caveat of high density flexible circuit boards with thin die is that they can be very fragile. The use of back side films and underfill can protect the die making circuits more robust. For underfill to work well it requires good adhesion to the circuit board which can mean that flux residues under the die normally must be removed prior to underfilling.
Technical Library | 2014-04-03 18:01:13.0
A system level modeling methodology is presented and validated on a simple case. It allows precise simulations of electrostatic discharge (ESD) stress propagation on a printed circuit board (PCB). The proposed model includes the integrated circuit (IC) ESD protection network, IC package, PCB lines, passives components, and externals elements. The impact of an external component on the ESD propagation paths into an IC is demonstrated. Resulting current and voltage waveforms are analyzed to highlight the interactions between all the elements of an operating PCB. A precise measurement technique was designed and used to compare with the simulation results. The model proposed in this paper is able to predict, with good accuracy, the propagation of currents and voltages into the whole system during ESD stress. It might be used to understand why failures occur and how to fix them with the most suitable solution.
Technical Library | 2014-06-23 14:50:52.0
It was unusual to see chip terminations change colors when tin lead solders were used but with the introduction of lead free reflow soldering and the corresponding increases in reflow temperatures terminations are now changing colors. Two conditions are present when reflow temperatures are increased for lead free solder alloys that leads to discoloration. Reflow temperatures are above the melting point of tin (Sn MP is 232oC). Air temperatures commonly used in forced convection reflow systems are high enough to both melt the tin plating on the termination allowing it to be pulled into the solder joint due to solder joint liquid solder surface tension leaving behind the exposed nickel barrier. Now those metal oxide colors will be visible due to high air temperatures during reflow.
Technical Library | 2015-01-26 15:30:00.0
In 2005 Raytheon Technical Services Company, now Raytheon Information, Intelligence and Services (Raytheon IIS), approached Ensil regarding the repair of their manufactured Radar Control Terminal (RCT) units. The RCT TRS P/N 13563090-2, a key component in the AN/MPQ-64 Sentinel System, consisted of outdated parts which caused minor to major unit failures. Ensil repaired the RCT's at every turn, correcting any component with the parts still in circulation (mother boards, displays, power supplies) to provide the client with the best available technology. These repairs were completed to military standards and kept the RCT effective, allowing for the Sentinel radar to remain operational. However, the supply of outdated parts was eventually no longer available. Ensil offered the best possible solution, utilizing the skills of their knowledgeable engineering staff, they would reverse engineer a new computer to replace the obsolete RCT while maintaining the same form, fit and function.
Technical Library | 2015-04-03 20:02:31.0
Understanding your process and how to minimize defects has always been important. Nowadays, its importance is increasing with the complexity of products and the customers demand for higher quality. Quality Management Solutions (QMS) that integrate real-time test and inspection results with engineering and production data, can allow the optimization of the entire manufacturing process. We will describe the cost and time benefits of a QMS system when integrated with engineering data and manufacturing processes. We will use real examples that can be derived from integrating this data. This paper also discusses the aspects of Quality Management Software that enables electronic manufacturers to efficiently deliver products while achieving higher quality, reduce manufacturing costs and cutting repair time. Key words: Quality Management Software, ICT, Repair workstations, First Pass Yield, Pareto analysis, Flying Probe, QMS.
Technical Library | 2016-01-12 11:07:56.0
With the increasing demand of device miniaturization, high speed, more memory, more function, low cost, and more flexibility in device design and manufacturing chain, YINCAE has published a white paper on a first individual solder joint encapsulant which can eliminate underfilling process with at least five times solder joint increase and provide more flexibility for fine pitch and high density application. In order to meet the demand of manufacturing of high speed and low cost, YINCAE has invented a room temperature stable and jettable solder joint encapsulant adhesive – SMT 266. The invention of SMT 266 has allowed our customers to have more flexibility in their high-speed production line such as worry free on the work life of adhesive and workable jetting process.
Technical Library | 2016-09-12 10:16:04.0
It is hard to open an Industry newsletter or visit an equipment manufacturer’s website without coming across a mention of the Internet of Things (IoT), Industry 4.0, SMART Manufacturing or ‘big data’. The accessibility to obtain data will only increase and this information and its real-time processing will become one of the most important resources for companies in the future. Production machinery will no longer simply processes the product, but the product will communicate with the machinery to tell it exactly what to do. Industry 4.0 has the vision to connects embedded system technologies and SMART production processes to drastically transform industry and production giving way to the SMART factory development. Future development in oven technology will allow machines to be controlled more intelligently and remotely resulting in the lowest cost model for manufacturing flow.
Technical Library | 2016-10-24 14:59:03.0
Temperature measurement is one of the most important physical parameters when determining quality, accuracy and reliability of processes not only in industrial use, but also in almost all human activities. Temperature sensors are produced with different technologies to fit specific application requirements. IST AG has concentrated one part of the development and manufacturing on high-end thin-film temperature sensors. This know-how is partially derived from the semiconductor industry and allows us to manufacture sensors with high accuracy, excellent long-term stability, high reliability and repeatability within a wide temperature range from -200 °C up to 1000 °C. Because of very small dimensions and low thermal mass, the thin-film temperature sensors exhibit a very short response time.
Technical Library | 2016-11-03 17:53:56.0
We present a novel method for fabricating a high-density carbon nanotube microelectrode array (MEA) chip. Vertically aligned carbon nanotubes (VACNTs) were synthesized by microwave plasma-enhanced chemical vapor deposition and thermal chemical vapor deposition. The device was characterized using electrochemical experiments such as cyclic voltammetry, impedance spectroscopy and potential transient measurements. Through-silicon vias (TSVs) were fabricated and partially filled with polycrystalline silicon to allow electrical connection from the high-density electrodes to a stimulator microchip.In response to the demand for higher resolution implants, we have developed a unique process to obtain a high-density electrode array by making the microelectrodes smaller in size and designing new ways of routing the electrodes to current sources.
Technical Library | 2018-12-12 22:20:22.0
Numerous 3D stack packaging technologies have been implemented by industry for use in microelectronics memory applications. This paper presents a reliability evaluation of a particular package-on-package (PoP) that offers a reduction in overall PCB board area requirements while allowing for increases in functionality. It utilizes standard, readily available device packaging methods in which high-density packaging is achieved by: (1) using standard "packaged" memory devices, (2) using standard 3-dimensional (3-D) interconnect assembly. The stacking approach provides a high level of functional integration in well-established and already functionally tested packages. The stack packages are built from TSOP packages with 48 leads, stacked either 2-high or 4-high, and integrated into a single dual-flat-no-lead (DFN) package.
