Description With the advent of CAD and CAM tools,the need arose for a more complete method of data transfer. As layer count increased,the number of files increased. As trace size and spacing began to decrease,the Gerber file size increased. The need ... read more

Description X ... read more

Description The migration to Lead Free raw materials in the Electronics Industry will happen faster than the date proposed in the original draft of the legislation. A true Pb-free solution for product such as high end and volume server and desktop requires printed ... read more

Description The Lead-free electronics manufacturing has become a reality. As of this writing,a few manufacturers have rightfully reported their total completion to Lead-free production across all facilities,and some have reached partial implementation. ... read more

Description This paper will demonstrate the effect high reflow temperatures in lead free processes will have on the reliability of printed circuit boards from a broad range of laminate materials for both traditional and lead-free processes. The focus will be on 24 ... read more

Description Motorola has been using embedded polymer thick film resistors on immersion silver-plated copper terminations in products for four years,and in the past year other firms have begun using this technology in their products. It is available to any ... read more

Description Novel configurations of decoupling capacitors were formed by anodizing Ta,resulting in Ta2O5 films 2000 Å thick and k = 23,giving about 110 nF/cm2. Since the dielectric is very thin,the parasitic inductance is almost unmeasurable,and is shown ... read more

Description We have previously published our work on developing thin substrates for use as embedded capacitor layers. Based on this work we have continued to characterize the performance and reliability of these materials. ... read more

Description The newly developed Ohmega-Ply “Resistor-Built-in-Trace” technology uses low-ohmic resistive materials for embedded resistors congruent to the circuitry in a multilayer PCB or HDI substrate. High frequencies and miniaturization has created ... read more

Description This paper will discuss the use of thin film buried resistors and thin core plane pairs in high layer count high reliability printed wiring boards used in single and double sided surface mount assemblies. Very high thermal stress durability is ... read more

Description Embedded passives technologies can provide benefits of size,performance,cost,and reliability to high density,highspeed designs. A number of embedded passive technology solutions are available to the designer. Based on our ... read more

Description Embedded passives,i.e.,resistors and capacitors built right into the printed circuit board substrate,is a rapidly emerging and pivotal technology for the PCB industry preceded only by the plated thru hole in the 50s and microvias in the 80s. ... read more

Description This paper discusses the work and testing performed to obtain extreme high reliability performance from high layer count, large panel format multilayer printed wiring boards that are used for backplanes in surface mount technology applications. ... read more

Description Driving factors for the use of via in pad technology include the growing trend towards more dense and complex printed circuit board designs as well as the need to minimize parasitic capacitance and inductance on high speed digital circuits. ... read more

Description This paper will describe the method used to automate drawing note creation at Lockheed Martin. It will discuss the reasons for the automation and some of the decisions that needed to be made before automation could take place. This paper will ... read more

Description The outlook for optical PCBs is unclear for mainly three reasons: 1) today's limits for copper boards can be stretched with design and manufacturing improvements,2) the market demand for next generation,higher bandwidth telecom systems (in ... read more

Description The lack of consistency and compatibility in process carrier designs was cited as an early barrier to automation in the nascent fiber-optics industry. Under the auspices of the National Electronics Manufacturing Initiative (NEMI),a working ... read more

Description Results from a National Electronics Manufacturing Initiative (NEMI) project,formed to improve aspects of fiber optic fusion splicing,are reported. The focus of this paper is ultra low loss splicing for telecommunications product assembly,with ... read more

Description When we think of optoelectronics in the USA,we automatically think of telecom applications. These fueled huge growth at the turn of the millennium,and even after the bubble burst in 2001-2,telecom represented a significant business and the ... read more

Description A cyclic board-bending technique has been developed to ensure a reproducible multiaxial stress state at the Chip Size Package (CSP) solder fillet. Mechanically stressing the package serves as a valuable tool to quickly determine ... read more

Description The miniaturization trend in electronics has proliferated the use of Chip Scale Packages (CSPs) in electronics assembly. CSPs used in portable devices are subjected to harsh mechanical and thermal conditions and underfill provides a dramatic ... read more

Description Chip scale packages (CSPs) are widely used in portable electronic products where there is also a growing trend to lead free assembly. Many CSP designs will meet the thermal cycle or thermal shock requirements for these applications. However, ... read more

Description The ever-increasing use of high frequency in high density interconnect (HDI) assemblies,combined with the worldwide move toward lead-free manufacturing,has initiated a closer scrutiny towards effective flux removal processes. Since ... read more

Description Lead-free alloys under consideration have physical properties,which may directly impact industry standard electronic assembly cleaning processes. The purpose of this study is to evaluate how the use of nitrogen versus non-nitrogen reflow atmospheres affect the ... read more

Description Conductive Anodic Filamentation is a subsurface failure mode for woven glass reinforced laminates (FR4) materials,where a copper salt filament allows bridging between via walls or other copper conductors. In this study FR4 laminates,in the form of ... read more

Description Various test methods are used to characterize the PCB plated-thru-hole reliability. One such method is the Interconnect Stress Test (IST). The results from this test are often used to qualify PCB materials and/or fabricators. This paper will discuss how ... read more

Description The selection and use of solder joint modification configurations for printed wiring assemblies has traditionally been a design specific activity. The implementation and use of a standardized set of solder joint modification configurations on an industrywide ... read more

Description A variety of mechanical and thermal stress related problems related to Flip Chip Ball Grid Array Packages (FCBGAs) are often solved by the Finite Element Method. Often,the question for the stress analyst is how to simplify the problem at hand ... read more

Description A new,green epoxy mold compound has been developed to encapsulate fine pitch PBGA and 3D-stacked die CSP packages. When evaluated on these packages,the compound provided very good wire sweep performance. It also has the ability for ... read more

Description As the need for higher performance,higher I/O count packaging solutions at lower costs continues to grow,opportunities exist to support these applications with higher performance wire bonded packages,as an alternative to some of the more expensive FlipChip solutions. ... read more

Description The world-wide movement to phase out lead from electronic products presents many challenges for companies throughout the electronics supply chain. The University of Massachusetts Lowell has brought together nine Massachusetts firms to ... read more

Description The continued functional densification and integration in networking products is driving the need to study large form factor printed circuit boards that use high I/O packages (either ceramics column grid arrays,CCGA,or plastic ball grid array, ... read more

Description Movements to lead-free assembly are being influenced by legislative and market requirements. Specifically Europe has passed legislation requiring the removal of lead from electronics assembly by 2006. Also,the perceived marketing advantage ... read more

Description For SnAgCu solders,the voiding rate at microvia was studied with the use of simulated microvia,and was the lowest with 95.5Sn3.8Ag0.7Cu and 95.5Sn3.5Ag1Cu. The voiding rate increased with decreasing Ag content from 3.5Ag,mainly due to ... read more

Description This paper presents a quantitative analysis of solder joint reliability data for lead-free Sn-Ag-Cu (SAC) and mixed assembly (SnPb + SAC) circuit boards based on an extensive,but non-exhaustive,collection of thermal cycling test results. The ... read more

Description As we inch towards the somewhat shifting deadlines towards lead (Pb) restriction in Japan and Europe,there is an increase seen in the amount of studies performed for electronics assemblies soldered with Pb-free alloys. This paper presents results of ... read more

Description The commercial use of lead-free solder has been making significant gains worldwide in recent years. To identify the effects of thermo-mechanical stress on Sn-Ag-Cu and Sn-Zn-Bi solder with different lead finishes (Sn-10Pb,Ni/Pd/Au plating),we ... read more

Description Developing lead free connector products involves at least two distinct steps: removing the lead from the product and ensuring the product has sufficient thermal stability. Lead is most commonly found in terminal finishes and has been removed from ... read more

Description An issue that has emerged from the increasing use by the electronics industry of lead-free solders in mass production wave soldering is the erosion of the copper of printed circuit board patterns and component terminations and the stainless steel of ... read more

Description Major industrial nations,around the world,are rapidly moving to eliminate lead from the electronic manufacturing processes. While some companies are taking advantage of the situation and are using “lead-free” as a major marketing initiative in the ... read more

Description The hypothesis that the “whisker growth phenomenon” in electrodeposited tin is a re-crystallization process driven by stress has gained popularity among leading research institutes and industrial laboratories. However,there exist varying opinions as ... read more

Description Tombstoning of SnAgCu is affected by the solder composition. At vapor phase soldering,both wetting force and wetting time at a temperature well above the melting point have no correlation with the tombstoning behavior. Since tombstoning is ... read more

Description Whilst the number of new ASIC designs has decreased over the last couple of years,there has been a dramatic increase in the number of FPGA designs implemented. Not only have the number of designs increased rapidly,the complexity and also the ... read more

Description As digital data rates reach 5Gb/s,10Gb/s and beyond,digital designers are finding it increasingly difficult to meet their design constraints using FR4. While there are a host of alternative materials available,cost constraints often prohibit the use ... read more

Description The electrical properties of PCB substrates are one of the primary factors used in designing high-frequency printed circuit boards. The loss tangent is the electrical property used by material suppliers to characterize the signal integrity of the PCB ... read more

Description The need for dynamic compact models for Integrated Circuits (ICs) is a well-recognized problem in electronics cooling simulations of electronic systems. Simplified thermal models have been reported in literature to simulate steady-state and ... read more

Description Microvias are the fastest growing new technology for printed circuits. Once you understand the basics,the advanced topics bring the real advantage to light. This talk will highlight the procedures and conditions that designers needs to consider ... read more

Description In most of today's high speed digital interconnects,the signal loss associated with the printed circuit board (PCB) is the dominate factor. Material selection,trace geometry,and choice of copper foil all play a role in establishing the signal loss ... read more

Description Traditional reduced black oxide processes for inner layer bonding have been superseded by a newer generation of peroxidesulfuric texturing processes. These lower cost processes,based on an organically controlled microetch,have proven to be ... read more

Description PTFE material is very hydrophobic and among the most difficult to deposit electroless copper or direct metallization. These materials have very low friction,which makes a surface non-wettable. Plasma technology has the ability to create wettable ... read more