Electronics Manufacturing Technical Articles

Modeling And Optimizing Wire Harness Costs For Variation Complexity

Apr 25, 2018 | Sjon Moore

An automotive wire harness rarely has just a single part number that can be ordered and installed in a vehicle. Typically, there are many different versions of the same harness based on the orderable content in the vehicle. These versions (often called harness levels) will have unique part numbers. The quantity of these levels and their content is what is typically called complexity and it has a significant impact on the cost of the harness.

Quantifying these costs is often very difficult especially with manual methods of deriving and costing the complexity solution. Therefore, traditionally, harness costing has focused on the piece cost of each harness level. When these complexity related costs are considered it is typically with overly simplified cost modeling techniques.

This paper will focus on the quantification of these complexity related costs so that they can be modeled allowing automated algorithms to optimize for these costs. A number of real world examples will be provided as well. Since no two businesses are alike, it is the aim of this paper to provide the foundational knowledge and methodology so the reader can assess their own business to model how variation complexity costs affect their business....

Publisher: Mentor Graphics

Semi-Additive Process for Low Loss Build-Up Material in High Frequency Signal Transmission Substrates

Apr 18, 2018 | Fei Peng, Naomi Ando, Roger Bernards, Bill Decesare

Higher functionality, higher performance and higher reliability with smaller real estate are the mantras of any electronic device and the future guarantees more of the same. In order to achieve the requirements of these devices, designs must incorporate fine line and via pitch while maintain good circuitry adhesion at a smooth plating-resin interface to improve signal integrity. The Semi-Additive Process (SAP) is a production-proven method used on low dielectric loss tangent (Df) build-up materials that enables the manufacture of ultra-fine circuitry. (...)

This paper will discuss a new SAP process for low loss build-up materials with low desmear roughness (Ra= 40-100 nm) and excellent adhesion (610-680 gf/cm) at various processing conditions. Along with the process flow, the current work will also present results and a discussion regarding characterization on the morphology and composition of resin and/or metal plating surfaces using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), surface roughness analysis, plating-resin adhesion evaluation from 90o peel tests...

Publisher: MacDermid Inc.

Understanding Circuit Material Performance Concerns for PCBs at Millimeter-Wave Frequencies

Apr 11, 2018 | John Coonrod

Millimeter-wave (mmWave) frequency applications are becoming more common. There are applications utilizing PCB technology at 60 GHz, 77 GHz and many other mmWave frequencies. When designing a PCB for mmWave frequency, the properties of the circuit materials need to be considered since they can be critical to the success of the application. Understanding the properties of circuit materials at these frequencies is very important.

This paper will give an overview of which circuit material properties are important to mmWave frequency applications using PCBs. There will be data supplied which demonstrates why these properties are essential to the circuit material selection for mmWave applications. Some properties discussed will be dielectric constant (Dk) control, dissipation factor, moisture absorption, thickness control and TCDk (Temperature Coefficient of Dk). Measured comparisons will be shown for insertion loss and Dk versus frequency for different types of circuit materials up to 110 GHz. As part of the test data, the impact on circuit performance due to TCDk and moisture absorption will be shown at mmWave frequencies....

Publisher: Rogers Corporation

High Reliability and High Throughput Ball Bumping Process Solution – Solder Joint Encapsulant Adhesives

Apr 05, 2018 | Dr. Mary Liu and Dr. Wusheng Yin

The miniaturization of microchips is always driving force for revolution and innovation in the electronic industry. When the pitch of bumps is getting smaller and smaller the ball size has to be gradually reduced. However, the reliability of smaller ball size is getting weaker and weaker, so some traditional methods such as capillary underfilling, corner bonding and edge bonding process have been being implemented in board level assembly process to enhance drop and thermal cycling performance. These traditional processes have been increasingly considered to be bottleneck for further miniaturization because the completion of these processes demands more space. So the interest of eliminating these processes has been increased. To meet this demand, YINCAE has developed solder joint encapsulant adhesives for ball bumping applications 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. In this paper we will discuss the ball bumping process, the reliability such as strength of solder joints, drop test performance and thermal cycling performance. ...

Publisher: YINCAE Advanced Materials, LLC.

Screen Making for Printed Electronics- Specification and Tolerancing

Mar 28, 2018 | Jesse Greenwood

Six decades of legacy experience makes the specification and production of screens and masks to produce repeatable precision results mostly an exercise in matching engineering needs with known ink and substrate performance to specify screen and stencil characteristics. New types of functional and electronic devices, flex circuits and medical sensors, industrial printing, ever finer circuit pitch, downstream additive manufacturing processes coupled with new substrates and inks that are not optimized for the rheological, mechanical and chemical characteristics for the screen printing process are becoming a customer driven norm. Many of these materials do not work within legacy screen making, curing or press set-up parameters. Many new materials and end uses require new screen specifications.

This case study presents a DOE based method to pre-test new materials to categorize ink and substrate rheology, compatibility and printed feature requirement to allow more accurate screen recipes and on-press setting expectations before the project enters the production environment where time and materials are most costly and on-press adjustment methods may be constrained by locked, documented or regulatory processes, equipment limitations and employee experience....

Publisher: Hazardous Print Consulting Inc

Using Lean Six Sigma to Optimize Critical Inputs on Solder Paste Printing

Mar 21, 2018 | Tom Watson

Solder paste printing is the first step in the surface mount manufacturing process for PCBA assembly. When the solder paste printing process is uncontrolled, defects can be produced, which may not become apparent until the PCBA is downstream. (...)

This paper will discuss how Lean Six Sigma techniques were used to optimize the solder paste printing process. It will highlight how a cross-functional team used the structured Define, Measure, Analyze, Improve and Control (DMAIC) methodology to identify and control the critical inputs. The advantage of the Lean Six Sigma methodology is that it guides the team through the rigorous structured process so that all possible inputs are considered and the critical ones can be identified....

Publisher: Kimball Electronics, Inc.

SMT Stencil, Surface Performance Returning to Basics in the SMT Screen Printing Process to Significantly Improve the Paste Deposition

Mar 15, 2018 | JimVillalvazo

The SMT assembly process is continuously challenged by the factors which enhance circuit board performance and limit productivity. The pick and place and reflow systems reflect these driven issues by adding more and more controls to their systems, but the fact is one of the age old processes continues to operate within the same rules since the dawn of the SMT assembly world: The SMT screen printing. (...)

This paper showcases a new stencil process that was discovered by reverting to the basics:understanding the reason for each stencil material process, focusing on detailed finishes and a disciplined aperture design process, maintaining original designs, and making the correctly designed apertures to control the paste deposition. The test results drove us to focus the efforts on the aperture walls In this paper we will demonstrate with lab tests SMT process results howthe improved paste release results in improved SMT print process performance and its positive impact on SPI yields and EOL performance....

Publisher: InterLatin

PCB Assembly With Obsolete Parts and Hard-To-Find Components

Mar 13, 2018 | Tuan Tran

Many companies take their supply chain for granted until they need an obsolete part or a hard-to-find component. Then the importance of having resourceful contract manufacturing partners becomes an incredibly valuable asset....

Publisher: Power Design Services

Optimization of Stencil Apertures to Compensate for Scooping During Printing

Mar 07, 2018 | Gabriel Briceno, Ph. D., Miguel Sepulveda

This study investigates the scooping effect during solder paste printing as a function of aperture width, aperture length and squeegee pressure. The percent of the theoretical volume deposited depends on the PWB topography. A typical bimodal percent volume distribution is attributed to poor release apertures and large apertures, where scooping takes place, yielding percent volumes <100%, while SMD apertures and apertures near PWB features that raise the stencil yield percent volumes >100%. This printing experiment is done with a concomitant validation of the printing process using standard 3D Solder Paste Inspection (SPI) equipment....

Publisher: Qual-Pro Corporation

Design and Process Development for the Assembly of 01005 Passive Components

Mar 05, 2018 | J. Li, S. Poranki, K. Srihari - Watson Institute for Systems Excellence, R. Gallardo, M. Abtew, R. Kinyanjui - Sanmina-SCI Corporation

Growing demands for smaller electronic assemblies has resulted in reduced sizes of passive components, requiring the introduction of newer components, such as the 01005 devices. Component miniaturization presents significant challenges to the traditional surface mount assembly process. A successful assembly solution for these 01005 devices should be repeatable and reproducible, and should include guidelines for (i) the selection of solder paste and (ii) appropriate stencil and substrate pad design, and should ensure strict process control standards....

Publisher: Sanmina-SCI

Stencil Design for Lead-Free SMT Assembly

Mar 05, 2018 | Chrys Shea

In order to comply with RoHS and WEEE directives, many circuit assemblers are transitioning some or all of their soldering processes from tin-lead to lead-free within the upcoming year. There are no drop-in replacement alloys for tin-lead solder, which is driving a fundamental technology change. This change is forcing manufacturers to take a closer look at everything associated with the assembly process: board and component materials, logistics and materials management, solder alloys and processing chemistries, and even soldering methods.

Do not expect a dramatic change in soldering behavior when moving to lead-free solders. The melting points of the alloys are higher, but at molten temperatures the different alloys show similar behaviors in a number of respects. Expect subtler changes, especially near the edges of a process window that is assumed based on tin-lead experience rather than defined through lead-free experimentation. These small changes, many of them yet to be identified and understood, will manifest themselves with lower assembly yields. The key to keeping yields up during the transition to lead-free is quickly learning what and where the subtle distinctions are, and tuning the process to accommodate them....

Publisher: Cookson Electronics

Troubleshooting SMT Solder Paste Problems

Mar 05, 2018 | Heraeus

Troubleshooting SMT Solder Paste Problems...

Publisher: Heraeus

Deposition of Solder Paste into High Density Cavity Assemblies

Feb 28, 2018 | Fernando Coma, Jeffrey Kennedy, Thilo Sack

Circuit functional density requirements continue to drive innovative approaches to high performance packaging. Some new approaches include; aggressive space reduction, embedded solutions, and those that offer some form of risk reduction and rework potential are now options that are being explored by customers. Requirements for assembly of these types of packages necessitate the deposition of solder paste and assembly of components into cavities of the substrates to gain z-axis density as well as area functional density. Advances in the fabrication of PWB’s with cavities using newly developed laser micro-fabrication processes along with increased circuit pitch density of 50 micron lines and spaces permit new applications for high performance electronic substrates.

First published at SMTA Pan Pacific Symposium...

Publisher: Celestica Corporation

Hand Soldering with Lead Free Alloys

Feb 22, 2018 | Metcal

As companies start to implement lead free soldering processes, hand soldering and associated techniques have been identified as key functions in the manufacturing process requiring additional research and development. Hand soldering tends to occur at the end of the process line where the circuit board has a high intrinsic value and so correct process control will have a significant affect on manufacturing costs and productivity.

This paper discusses the fundamental aspects of the hand soldering process and discusses process adaptation requirements for successful lead free implementation....

Publisher: Metcal

Making a Rigid Industry More Flexible

Feb 21, 2018 | Tuan Tran

Flex Circuits and Rigid-Flex Boards Are Taking Off...

Publisher: Power Design Services

What Makes Flex Circuit Assembly Different?

Feb 18, 2018 | Tuan Tran

Flex circuits allow manufacturers to be more creative than ever....

Publisher: Power Design Services

Design Rules For Selective Soldering Assemblies

Feb 14, 2018 | Vitronics Soltec Oosterhout

This document describes general guidelines and attention points for PCB design regarding selective soldering. The guidelines can be applied for Select Wave and/or Multi Wave soldering process in both leaded and leadfree alloy. When a PCB is designed according to these guidelines, a stable and solid solder-process can be guaranteed....

Publisher: Vitronics Soltec

Mixed Voltages And Aluminum Conductors: Assesing New Electrcal Technology

Feb 07, 2018 | Olivier Neuman

The architecture of vehicle electrical systems is changing rapidly. Electric and hybrid vehicles are driving mixed voltage systems, and cost pressures are making conductor materials like aluminum an increasingly viable competitor to copper.

This paper presents tradeoff studies at the vehicle level, and how to automatically generate an electrical Failure Mode Effects and Analysis (FMEA) report, as well as how to optimize wire sizes for both copper and aluminum at the platform level....

Publisher: Mentor Graphics

Electronic Does Not Equal Smart: Service Documentation and Brand Quality

Feb 01, 2018 | Muhammad Askar

This paper briefly summarizes the technologies underpinning the evolution in electrical system diagnosis and repair, which include schematic layout automation using prototypes and rule-based styling, instant language translation, 2D/3D view links with schematics, interactive diagnostic procedures, and dynamically-generated signal-tracing diagrams. These technologies empower after-sales service teams with state-of-the-art capabilities, which not only reduce costs but also improve brand quality in the eyes of its customers. ...

Publisher: Mentor Graphics

Fine Pitch Cu Pillar with Bond on Lead (BOL) Assembly Challenges for High Performance Flip Chip Package

Jan 17, 2018 | Nokibul Islam, Vinayak Pandey, KyungOe Kim

Fine pitch copper (Cu) Pillar bump has been growing adoption in high performance and low-cost flip chip packages. Higher input/output (I/O) density and very fine pitch requirements are driving very small feature sizes such as small bump on a narrow pad or bond-on-lead (BOL) interconnection, while higher performance requirements are driving increased current densities, thus assembling such packages using a standard mass reflow (MR) process and maintaining its performance is a real and serious challenge. (...)

In this study a comprehensive finding on the assembly challenges, package design, and reliability data will be published.

Originally published in the SMTA International 2016...

Publisher: STATS ChipPAC Inc

High-Performance Ink-Jet Printed Graphene Resistors Formed With Environmentally-Friendly Surfactant-Free Inks For Extreme Thermal Environments

Jan 11, 2018 | Monica Michel, Chandan Biswas, Anupama B. Kaul

Ink-jet printing is poised to impact the manufacturing of devices that are particularly attractive for flexible electronics, as more suitable and printable fluids become available. The addition of surfacants in the preparation of the inks usually results in additional process steps, potentially increasing cost, as well as material waste, where the surfactants also often have a negative impact on specific properties of the printed features, such as comprising electrical conductivity of metallic structures. (...)

In this work, we have successfully formulated a suitable ink derived from a mixture of terpineolin cyclohexanone as a more environmentally friendly option for the exfoliation of bulk graphite, which we elaborate upon in more detail here....

Publisher: University of Texas

IPC-1782 Standard for Traceability Supporting Counterfeit Components

Jan 04, 2018 | Michael Ford

Traceability has grown from being a specialized need for certain safety critical segments of the industry, to now being a recognized value-add tool for the industry as a whole. The perception of traceability data collection however persists as being a burden that may provide value only when the most rare and disastrous of events take place. Disparate standards have evolved in the industry, mainly dictated by large OEM companies in the market create confusion, as a multitude of requirements and definitions proliferate.

The intent of the IPC-1782 project is to bring the whole principle and perception of traceability up to date. Traceability, as defined in this standard will represent the most effective quality tool available, becoming an intrinsic part of best practice operations, with the encouragement of automated data collection from existing manufacturing systems, integrating quality, reliability, predictive (routine, preventative, and corrective) maintenance, throughput, manufacturing, engineering and supply-chain data, reducing cost of ownership as well as ensuring timeliness and accuracy all the way from a finished product back through to the initial materials and granular attributes about the processes along the way. ...

Publisher: Mentor Graphics

Top Reasons to Outsource IC Reworks on PCB

Dec 30, 2017 | Tuan Tran

Reworking printed circuit boards may require certain skills and tools to ensure quality results. When is it appropriate to outsource this work? ...

Publisher: Power Design Services

SMT Line or Manual PCB Assembly? When Hand Assembly Makes Sense

Dec 29, 2017 | Tuan Tran

Although PCB assembly is a highly automated process, there are times when manual PCB assembly makes sense for prototyping innovative tech products. ...

Publisher: Power Design Services

Article Design and Experiment of a Solder Paste Jetting System Driven by a Piezoelectric Stack

Dec 27, 2017 | Shoudong Gu, Xiaoyang Jiao, Jianfang Liu *, Zhigang Yang, Hai Jiang and Qingqing Lv

To compensate for the insufficiency and instability of solder paste dispensing and printing that are used in the SMT production process, a noncontact solder paste jetting system driven by a piezoelectric stack based on the principle of the nozzle-needle-system is introduced in this paper, in which a miniscule gap exists between the nozzle and needle during the jetting process....

Publisher: Jilin University

Printing and Curing of Conductive Ink Track on Curvature Substrate using Fluid Dispensing System and Oven

Dec 21, 2017 | Rd K . Khirotdin, Nurhafizzah Hassan, Hi H. Siang, Muhamad H. Zawahid

The present work concerns on the use of sensors to monitor the structural health of wind turbine . Conventionally the inspection was made using non-contact sensing during the turbine’s inoperable period hence loss occurred. A real -time monitoring system via embedded wireless sensor is preferred but the sensor could only be implanted using non-contact printing method due to most turbine blade s’ curved surface. Conductive ink associate d with non-contact printing method via fluid dispensing system are proposed since conductive inks are proven stretchable and fluid dispensing system enables printing on various substrates and works well with any materials......

Publisher: University of Tun Hussein Onn

PCB Sourcing Using PCQR 2

Dec 13, 2017 | Al Block, Naji Norder, Chris Joran

In a global market, it is often difficult to determine the best PCB suppliers for your technology needs, while also a chieving the lowest costs for your products. Considering each PCB supplier has their own niche in t erms of equipment, process, and performance, uniform test data from the IPC -9151D Process Capability, Quality, and Relative Reliability (PCQR 2 ) Benchmark Test Standard can help find the right source for the board based on its specific technology requirements. By using a data-based approach to vendor selection, this can remove the subjective nature of sourcing, reduce the need for PCB process experts to map suppliers into technologies, and eliminate irrational sourcing decisions....

Publisher: National Instruments

Cost effective solution in SMT production: AI and Big Data

Dec 12, 2017 | Alexei Shkolnik (Proventus Technologies)

In recent years, more and more companies with SMT production floor are trying to become more efficient and cut production costs. In most cases, the treatment was carried out problematic processes that visible and easy to find. Now these companies came to look problematic processes that are invisible and hard to find....

Publisher: Proventus Technologies

Contamination Profile of Printed Circuit Board Assemblies in Relation to Soldering Types and Conformal Coating

Dec 11, 2017 | Hélène Conseil, Morten S. Jellesen, Rajan Ambat

Typical printed circuit board assemblies (PCBAs) processed by reflow, wave, or selective wave soldering were analysed for typical levels of process related residues, resulting from a specific or combination of soldering process. Typical solder flux residue distribution pattern, composition, and concentration are profiled and reported. Presence of localized flux residues were visualized using a commercial Residue RAT gel test and chemical structure was identified by FT-IR, while the concentration was measured using ion chromatography, and the electrical properties of the extracts were determined by measuring the leak current using a twin platinum electrode setup. Localized extraction of residue was carried out using a commercial C3 extraction system. Results clearly show that the amount and distribution of flux residues are a function of the soldering process, and the level can be reduced by an appropriate cleaning. Selective soldering process generates significantly higher levels of residues compared to the wave and reflow process. For conformal coated PCBAs, the contamination levels generated from the tested wave and selective soldering process are found to be enough to generate blisters under exposure to high humidity levels....

Publisher: Technical University of Denmark

Utility of Dual Applicators for Non-Atomized Conformal Coating to Improve High-Volume Manufacturing Optimization

Dec 07, 2017 | Camille Sybert, Michael Szuch

Electronics manufacturers protect their circuit boards with conformal coatings. Conformal coatings serve as a barrier from environmental hazards and internal shorts, tin whiskers, and corrosion at the board level. Within conformal coatings different material chemistries specialize in shielding from an array of hazards and can be applied by multiple methods. The most common method is atomized spray which disperses the material into a fine mist. Alternatively, non-atomized coating controls the materials' dispense shape while maintaining the original liquid form. While some applications demand atomized spray and other scenarios overlap between atomized and non-atomized coating, this paper focuses on the circumstances where materials are ideally suited for non-atomized, selective coating....

Publisher: ASYMTEK Products | Nordson Electronics Solutions

Guide to Light-Cure Conformal Coating

Nov 30, 2017 | Dymax Corporation

Each year the electronics industry is faced with new product designs that call for smaller printed circuit boards (PCBs) to function in more aggressive and rigorous service environments. As demands change, conformal coating is becoming increasingly adopted to ensure PCB reliability in environments where moisture, condensation, dust, dirt, salts, chemicals, abrasion, thermal shock, mechanical shock, and other factors can all affect circuit performance. This guide reviews the benefits of using light-cure conformal coatings as well as cost justification, typical processing guidelines and best practices, product selection criteria, data, and industry specifications. ...

Publisher: Dymax Corporation

Factors Affecting the Adhesion of Thin Film Copper on Polyimide

Nov 22, 2017 | David Ciufo, Hsin-Yi Tsai and Michael J. Carmody

The use of copper foils laminated to polyimide (PI) as flexible printed circuit board precursor is a standard practice in the PCB industry. We have previously described[1] an approach to very thin copper laminates of coating uniform layers of nano copper inks and converting them into conductive foils via photonic sintering with a multibulb conveyor system, which is consistent with roll-to-roll manufacturing. The copper thickness of these foils can be augmented by electroplating. Very thin copper layers enable etching fine lines in the flexible circuit. These films must adhere tenaciously to the polyimide substrate.

In this paper, we investigate the factors which improve and inhibit adhesion. It was found that the ink composition, photonic sintering conditions, substrate pretreatment, and the inclusion of layers (metal and organic) intermediate between the copper and the polyimide are important....

Publisher: Intrinsiq Materials Inc.

Controlling Voiding Mechanisms in the Reflow Soldering Process

Nov 15, 2017 | Keith Sweatman, Takatoshi Nishimura, Kenichiro Sugimoto, Akira Kita

While a significant level of voiding can be tolerated in solder joints where electrical conductivity is the main requirement, voiding at any level severely compromises thermal conductivity. For example, in LED lighting modules effective conduction of heat through the 1st level die attach to the substrate and then through the 2nd level attach to the heat sink is critical to performance so that voiding in the solder joints at both levels must be minimized. (...) In this paper, the authors will review the factors that influence the incidence of voids in small and large area solder joints that simulate, respectively, the 1st and 2nd level joints in LED modules and discuss mitigation strategies appropriate to each level. They will also report the results of a study on the effect on the incidence of voids of flux medium formulation and the optimization of the thermal profile to ensure that most of the volatiles are released early in the reflow process....

Publisher: Nihon Superior Co., Ltd.

Why Design PCB Assemblies with Testing in Mind?

Nov 14, 2017 | Tuan Tran

Can you put a product that hasn't been fully tested on the market? When it comes to Printed Circuit Board (PCB) assembly and manufacturing, most firms’ answer is neither a strict yes or no. ...

Publisher: Power Design Services

Soldering fume in electronics manufacturing - damaging effects and solutions for removal

Nov 10, 2017 | ULT AG

Modern electronics manufacturing is made up by a multiplicity of different separation and joining processes, with the later surely taking the vast majority of production technology. Alongside gluing, welding and laser processes, soldering still holds a primary position in electronic assemblies. However, soldering does not always equal soldering, because there are quite a lot of different soldering technologies. Accordingly, you have to distinguish between automated and manual soldering procedures. No matter which soldering process you analyse, all of them have one aspect in common: they produce airborne pollutants, which may have a negative impact on employees, plants and products as well....

Publisher: ULT Canada Sales Incorporated

Void Reduction in Reflow Soldering Processes by Sweep Stimulation of PCB Substrate

Nov 08, 2017 | Viktoria Rawinski

Due to the ongoing trend towards miniaturization of power components, the need for increased thermal conductivity of solder joints in SMT processes gains more and more importance. Therefore, the role of void free solder joints in power electronics becomes more central. Voids developed during soldering reduce the actual thermal transfer and can cause thermal damage of the power components up to their failure. For this reason, the company has developed a new technique to minimize the formation of these voids during the soldering process....

Publisher: kurtz ersa Corporation

Solder Paste Printing – the Most Critical Part of Building a Quality PCB Explained

Nov 03, 2017 | Tuan Tran

If someone were to ask what the most important part of their favorite electronic device is, they are likely to point to the printed circuit board (PCB) responsible for making the device work before moving on to other components. From large motherboards to tiny chips, most of the technology that retail consumers take for granted comes down to a properly installed and calibrated PCB. ...

Publisher: Power Design Services

Just‐In‐Time Material Management for the PCB Industry

Nov 03, 2017 | Tuan Tran

As with any production industry, businesses in the PCB industry need to maintain a healthy balance between the components they keep in stock and those they use for meet client orders. Ordering too many components comes with serious disadvantages, as does not ordering enough, and PCB manufacturers need to stay as close as possible to a happy medium between the two....

Publisher: Power Design Services

21st Century PCB FAB Factory Design Which Eliminates Regional Cost Advantages

Nov 01, 2017 | Alexander Stepinski

Over fifteen years has passed since North America and Europe ceased being the center of worldwide PCB fabrication, and were supplanted by a Far East market with low cost labor, more relaxed environmental requirements, and strong government support. In just a few short years, the superior cost advantages of this new dynamic put volume PCB production in the West out of business, aside for the military and specialty technology applications contained in the few shops that continue to exist today.

Recently, however, the conditions which created the current equilibrium appear to be shifting again. In this new dynamic, automation, innovative green wastewater technologies, and next generation process equipment innovations have combined to make new factories capable of achieving rapid ROI for PCB fabrication almost anywhere. This paper means to illustrate this new dynamic, and provide case study examples from the new greenfield installation at the company captive facility in New Hampshire....

Publisher: Whelen Engineering

Can Nano-Coatings Really Improve Stencil Performance?

Oct 26, 2017 | Tony Lentz

Nano-coatings have been introduced by various manufacturers, with the promise of addressing some of the challenges relative to solder paste printing. Stated benefits include: Reduced underside cleaning, reduced bridging, improved solder paste release and improvements in yield. With several nano technologies already on the market and more likely to be introduced, how can the performance be quantified? How robust are these coatings? How can an assembler approach the ROI of these coatings? What hidden benefits or negative impacts should be considered?

This paper will present a rigorous method for evaluating the performance and economic benefits of solder paste stencil nano-coatings....

Publisher: FCT ASSEMBLY, INC.

To Quantify a Wetting Balance Curve

Oct 19, 2017 | Frank Xu Ph.D., Robert Farrell, Rita Mohanty Ph.D.

Wetting balance testing has been an industry standard for evaluating the solderability of surface finishes on printed circuit boards (PCB) for many years. A Wetting Balance Curve showing Force as a function of Time, along with the individual data outputs "Time to Zero" T(0), "Time to Two-Thirds Maximum Force" T(2/3), and "Maximum Force" F(max) are usually used to evaluate the solderability performance of various surface finishes. While a visual interpretation of the full curve is a quick way to compare various test results, this method is subjective and does not lend itself readily to a rigorous statistical evaluation. Therefore, very often, when a statistical evaluation is desired for comparing the solderability between different surface finishes or different test conditions, one of the individual parameters is chosen for convenience. However, focusing on a single output usually doesn't provide a complete picture of the solderability of the surface finish being evaluated.

In this paper, various models here-in labeled as "point" and "area" models are generated using the three most commonly evaluated individual outputs T(0), T(2/3), and F(max). These models have been studied to quantify how well each describes the full wetting balance curve. The solderability score (S-Score) with ranking from 0 to 10 were given to quantify the wetting balance curve as the result of the model study, which corresponds well with experimental results....

Publisher: Enthone

High Reliability and High Temperature Application Solution - Solder Joint Encapsulant Paste

Oct 16, 2017 | Dr. Mary Liu and Dr. Wusheng Yin

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 300C, 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. ...

Publisher: YINCAE Advanced Materials, LLC.

Mitigation of Pure Tin Risk by Tin-Lead SMT Reflow- Results of an Industry Round-Robin

Oct 12, 2017 | David Pinsky - Raytheon Integrated Defense Systems, Tom Hester - Raytheon Space and Airborne Systems, Dr. Anduin Touw - The Boeing Company, Dave Hillman - Rockwell Collins

The risk associated with whisker growth from pure tin solderable terminations is fully mitigated when all of the pure tin is dissolved into tin-lead solder during SMT reflow. In order to take full advantage of this phenomenon, it is necessary to understand the conditions under which such coverage can be assured. A round robin study has been performed by IPC Task group 8-81f, during which identical sets of test vehicles were assembled at multiple locations, in accordance with IPC J-STD-001, Class 3. All of the test vehicles were analyzed to determine the extent of complete tin dissolution on a variety of component types. Results of this study are presented together with relevant conclusions and recommendations to guide high reliability end-users on the applicability and limitations of this mitigation strategy....

Publisher: Raytheon

Intermetallic Compounds In Solar Cell Interconnections Including Lead-Free, Low Melting Point Solders

Oct 05, 2017 | Torsten Geipel, Achim Kraft, Ulrich Eitner - ISE, Monja Moeller - Kiel University

Intermetallic compounds (IMC) in solder bonds are commonly considered critical for the reliability of interconnections. The microstructure and thermal aging characteristics of solder bonds of crystalline silicon solar cells are investigated, whereby two solders, Sn60Pb40 and a lead-free, low melting point alternative Sn41Bi57Ag2 are considered....

Publisher: Fraunhofer Insitute for Solar Energy Systems ISE

An Investigation into the Use of Nano-Coated Stencils to Improve Solder Paste Printing with Small Stencil Aperture Area Ratios

Sep 28, 2017 | Jasbir Bath, Tony Lentz, Greg Smith

These nano-coatings also refine the solder paste brick shape giving improved print definition. These two benefits combine to help the solder paste printing process produce an adequate amount of solder paste in the correct position on the circuit board pads. Today, stencil aperture area ratios from 0.66 down to 0.40 are commonly used and make paste printing a challenge.

This paper presents data on small area ratio printing for component designs including 01005 Imperial (0402 metric) and smaller 03015 metric and 0201 metric chip components and 0.3 mm and 0.4 mm pitch micro BGAs....

Publisher: FCT ASSEMBLY, INC.

Flex Circuit Manufacturing for Innovative Product Design

Sep 27, 2017 | Tuan Tran

Flex and rigid flex circuits have become increasingly popular in the high-density electronics industry for their cost-saving three-dimensional configurations. The ability to build circuitry to fit the device instead of the other way around, offers significant advantages for complex aerospace, military, and medical device applications....

Publisher: Power Design Services

Laser Wire Stripping for Medical Device Manufacturing Applications

Sep 25, 2017 | Pete Doyon, VP, Product Management, Schleuniger, Inc.

Laser wire stripping was developed by NASA in the 1970s as part of the Space Shuttle program. The technology made it possible to use smaller sized wires with thinner insulations, without risk of the damage that can be caused by traditional mechanical wire stripping methods. Laser wire stripping technology was commercialized in the 1990s and was initially used for aerospace and defense applications. Laser wire stripping then grew significantly when the consumer electronics market exploded as lasers became the only stripping solution for the tiny data cables found in laptops, mobile phones and other consumer electronics products. Another large industry that has adopted laser wire stripping methods, and for good reason, is high-end medical device manufacturing. ...

Publisher: Schleuniger, Inc.

2.5D and 3D Semiconductor Package Technology: Evolution and Innovation

Sep 14, 2017 | Vern Solberg

The electronics industry is experiencing a renaissance in semiconductor package technology. A growing number of innovative 3D package assembly methodologies have evolved to enable the electronics industry to maximize their products functionality. By integrating multiple die elements within a single package outline, product boards can be made significantly smaller than their forerunners and the shorter interconnect resulting from this effort has contributed to improving both electrical performance and functional capability. (...)

This paper outlines both positive and negative aspects of current 3D package innovations and addresses the challenges facing adopters of silicon and glass based interposer fabrication. The material presented will also reference 3D packaging standards and recognize innovative technologies from a number of industry sources, roadmaps and market forecasts....

Publisher: Vern Solberg - Solberg Technical Consulting

The Relationship Between Energy-Resource Depletion, Climate Change, Health Resources and the Environmental Kuznets Curve: Evidence From the Panel of Selected Developed Countries

Sep 13, 2017 | Syed Abdu lRehman Khan, Khalid Zaman, YuZhang

The objective of the study is to examine the relationship between energy-resource depletion, climate change, health resources and the Environmental Kuznets Curve(EKC) under the financial constraint environment in the panel of selected developed countries, over the period of 2000–2013....

Publisher: Changan University

Challenges on ENEPIG Finished PCBs: Gold Ball Bonding and Pad Metal Lift

Sep 07, 2017 | Young K. Song and Vanja Bukva

As a surface finish for PCBs, Electroless Nickel/Electroless Palladium/Immersion Gold (ENEPIG) was selected over Electroless Nickel/Immersion Gold (ENIG) for CMOS image sensor applications with both surface mount technology (SMT) and gold ball bonding processes in mind based on the research available on-line. Challenges in the wire bonding process on ENEPIG with regards to bondability and other plating related issues are summarized....

Publisher: Teledyne DALSA