Electronics Manufacturing Technical Articles

Applied Statistics and Experimental Design

Jul 16, 2023 | Fritz Scholz

Statistics originally served to describe matters of the state (status of state) by capturing numerically various aspects of full populations. Today this is called a census, from Latin censere (to count or estimate). Recall the historical census of Emperor Augustus. Nowadays the field of statistics focusses mainly on samples, i.e., part of the total. The goal is to make statements or conclusions about the whole population. This process is referred to as induction, from Latin inducere (to lead to). Its validity depends crucially on the process of sampling. Sample   example from Latin exemplum.

Publisher: University of Washington

Design of Experiment Methods in High Speed Signal Via Transition in Printed Circuit Board

Jul 16, 2023 | Amir A. Asif,

With increase in data transfer speeds between integrated circuits, memories and connectors, the interconnects in printed circuit boards require careful design and optimization. A critical part of an interconnect is via transition. To meet the design goals and maintain signal integrity, every part of the interconnect needs to be carefully designed. Designing via involves variation of several parameters and it is extremely important to understand their contribution to find the usable parameters yielding best possible performance. Out of these numerous combinations of parameters, Design of Experiments (DOE) can offer much needed understanding, suggest possible values and speed up the design process. In this manuscript, two DOE methods (Box-Behnken Design and Central Composite Design) are used to understand the behavior of a pair of vias operating in differential mode.

Publisher: Clemson University

The Compensation Problem and Solution Using Design of Experiments for Dense Multilayer Printed Circuit Boards

Jul 16, 2023 | Wm. Gray McQuarrie

Imagine being able to accurately predict the correct artwork compensations prior to taking on a large quick turn order regardless of the board design, materials, or process. Such predictive power is possible and can be achieved without a lot of cost and complexity. This paper shows how small sets of designed experiments can be used to create a cImagine being able to accurately predict the correct artwork compensations prior to taking on a large quick turn order regardless of the board design, materials, or process. Such predictive power is possible and can be achieved without a lot of cost and complexity. This paper shows how small sets of designed experiments can be used to create a compensation model. Before a discussion of the design of experiments (DOEs), we will examine key processes and material variables that affect movement as demonstrated on real board design layout in a real production process. Only the few most relevant variables need to be included in the experimental design. A solution is presented that uses small experiments that provide the required information for constructing a general compensation model.mpensation model. Before a discussion of the design of experiments (DOEs), we will examine key processes and material variables that affect movement as demonstrated on real board design layout in a real production process. Only the few most relevant variables need to be included in the experimental design. A solution is presented that uses small experiments that provide the required information for constructing a general compensation model....

Publisher: Isola Group

Verifying the efficiency of soldering fume extraction and measuring nanoparticle exposure during soldering with an iron with the testo DiSCmini

Jul 10, 2023 | Testo

That manual soldering produces harmful substances in the form of aerosols is a known problem in the electric and electronic industry. The lead-free electronics solders used today have done little to change that. The soldering fumes still contain particles which are formed by the solder and the flux agent. These particles have a high potential of causing permanent damage to the workers’ health. Due to their small diameter between 10 and 150 nm, they can penetrate all the way into the alveoli. But numerous studies also show that nanoparticles can reach all areas of the body through the bloodstream [1].

Publisher: Testo SE & Co. KGaA

CLEANING BEFORE CONFORMAL COATING

Jul 04, 2023 | Naveen Ravindran

CONTENT * Introduction * Failure Mechanisms * Coating Failures * Cleaning Before Conformal Coating * Analytics & Test Methods...

Publisher: ZESTRON Americas

Conformal Coating Defects

Jul 04, 2023 | Diamond MT

Conformal Coatings are polymeric materials used to protect circuitry, parts, and related components. They are most commonly used to protect printed circuit boards (PCBs) and electronic devices. However, conformal coatings can be applied to a wide variety of materials, including metal, plastic, silicone, ceramics, glass, and even paper. We use the term "substrate" to refer to an object or material that's been coated with a conformal coating....

Publisher: Diamond MT

The Effects of Silver Content and Solidification Profile on the Anand Constitutive Model for SAC Lead Free Solders

Jun 14, 2023 | Munshi M. Basit, Mohammad Motalab, Jordan C. Roberts, Jeffrey C. Suhling, Pradeep Lall

In the electronic packaging industry, it is important to be able to make accurate predictions of board level solder joint reliability during thermal cycling exposures. The Anand viscoelastic constitutive model is often used to represent the material behavior of the solder in finite element simulations. This model is defined using nine material parameters, and the reliability prediction results are often highly sensitive to the Anand parameters. In this work, an investigation on the Anand constitutive model and its application to SAC solders of various Ag contents (i.e. SACN05, with N = 1, 2, 3, 4) has been performed. For each alloy, both water quenched (WQ) and reflowed (RF) solidification profiles were utilized to establish two unique specimen microstructures, and the same reflow profile was used for all four of the SAC alloys so that the results could be compared and the effects of Ag content could be studied systematically....

Publisher: Auburn University

Using Stencil: Design to Reduce SMT Defects

Jun 12, 2023 | Paul Lotosky, Michael Murphy, Robert Pearson, Michael Tesch

Solder paste printing is understood to be the leading contributor of defects in the electronics assembly process. Because yield accounts for such a large percentage of the margin, the greatest opportunity to improve profitability in the assembly of most electronics can be gained by reducing or eliminating solder defects. This article examines process adjustments made through stencil design that correct a misalignment situation between the PCB and stencil, leading to a 43% reduction in assembly defects. Examples of each are found in Table 1....

Publisher: AVI Precision Engineering Pte Ltd

Optimizing Stencil Design For Lead-Free Smt Processing

Jun 12, 2023 | Ranjit S Pandher, Chrys Shea

As any new technology emerges, increasing levels of refinement are required to facilitate the mainstream implementation and continual improvement processes. In the case of lead-free processing, the initial hurdles of alloy and chemistry selection are cleared on the first level, providing a base process. The understanding gained from early work on the base process leads to the next level of refinement in optimizing the primary factors that influence yield. These factors may include thermal profiles, PWB surface finishes, component metallization, solder mask selection or stencil design....

Publisher: Cookson Electronics Assembly Materials

The Effect of Higher Stencil Tension on Printing Performance

Jun 12, 2023 | Tom Meeus, Jan Van Lieshout, Hans Korsse, Sathiya Naryana

In this article we will examine if there is a measurable difference in the printing performance when using stencils which have a higher tension than is commonly accepted in the industry. Alpha's new tensoRED™ High Tension Frame System will be introduced during this wider examination. We will examine their effect in terms of controlling variation in critical deposit volumes and what, if any effect on positional accuracy can be seen....

Publisher: Alpha Assembly Solutions

Stencil Printing Process Tools for Miniaturisation and High Yield Processing

Jun 12, 2023 | Clive Ashmore & Mark Whitmore

The SMT print process is now very mature and well understood. However as consumers continually push for new electronic products, with increased functionality and smaller form factor, the boundaries of the whole assembly process are continually being challenged. Miniaturisation raises a number of issues for the stencil printing process. How small can we print? What are the tightest pitches? Can we print small deposits next too large for high mix technology assemblies? How closely can we place components for high density products? ...And then on top of this, how can we satisfy some of the cost pressures through the whole supply chain and improve yield in the production process! Today we are operating close to the limits of the stencil printing process. The area ratio rule (the relationship between stencil aperture opening and aperture surface area) fundamentally dictates what can and cannot be achieved in a print process. For next generation components and assembly processes these established rules need to be broken! New stencil printing techniques are becoming available which address some of these challenges. Active squeegees have been shown to push area ratio limits to new boundaries, permitting printing for next generation 0.3CSP technology. Results also indicate there are potential yield benefits for today's leading edge components as well. Stencil coatings are also showing promise. In tests performed to date it is becoming apparent that certain coatings can provide higher yield processing by extending the number of prints that can be performed in-between stencil cleans during a print process. Preliminary test results relating to the stencil coating technology and how they impact miniaturisation and high yield processing will be presented....

Publisher: ASM Assembly Systems (DEK)

Stencil Design For Mixed Technology Through-Hole / Smt Placement And Reflow

Jun 12, 2023 | William E. Coleman, Denis Jean, Julie Bradbury

This paper will review stencil design requirements for printing solder paste around and in through-hole pads / openings. There is much interest in this procedure since full implementation allows the placement of both through-hole components as well as SMD's and the subsequent reflow of both simultaneously. This in turn eliminates the need to wave solder or hand solder through-hole components....

Publisher: Photo Stencil LLC

Recurrent Neural Network-Based Stencil Cleaning Cycle Predictive Modeling

Jun 12, 2023 | Haifeng Wang, Tian He, and Sang Won Yoon

This paper presents a real-time predictive approach to improve solder paste stencil printing cycle decision making process in surface mount assembly lines. Stencil cleaning is a critical process that influences the quality and efficiency of printing circuit board. Stencil cleaning operation depends on various process variables, such as printing speed, printing pressure, and aperture shape. The objective of this research is to help efficiently decide stencil printing cleaning cycle by applying data-driven predictive methods. To predict the printed circuit board quality level, a recurrent neural network (RNN) is applied to obtain the printing performance for the different cleaning aging. In the prediction model, not only the previous printing performance statuses are included, but also the printing settings are used to enhance the RNN learning. The model is tested using data collected from an actual solder paste stencil printing line. Based on the predicted printing performance level, the model can help automatically identify the possible cleaning cycle in practice. The results indicate that the proposed model architecture can predictively provide accurate solder paste printing process information to decision makers and increase the quality of the stencil printing process....

Publisher: Binghamton University

The Solder Paste Printing Process: Critical Parameters, Defect Scenarios, Specifications, And Cost Reduction

Jun 12, 2023 | Chien-Yi Huang, Yueh-Hsun Lin, Kuo-Ching Ying, Chen-Liang Ku

The purpose of this paper is to comprehensively explore the effects of critical parameters on solder deposition and to establish a systematic approach for determining guidelines for solder paste inspection (SPI) workstations. Design/methodology/approach – This study explored the effects of process parameters, stencil and printed circuit board designs on solder deposition and identified the major post-reflow defect scenarios. Through the investigation of correlation between the results of SPI analysis and post-reflow defective scenarios, SPI specifications are suggested for minimizing the total cost of poor quality. Findings – The higher the printing pressure the lower the solder deposition. There was a significant difference in solder deposition between the front squeegee and the rear squeegee. Insufficient distance between the stencil aperture and the initial printing location resulted in irregular solder paste and variations in solder deposition. A stencil with a higher area ratio resulted in greater solder deposition and less variation. Stencil apertures parallel to the direction of printing were superior to a 458 vector print. Further, the nominal solder thickness should take into account the thicknesses of the solder mask and the legend ink. There was an offset in the results of SPI measurements between the solder mask defined (SMD) pads and non-SMD pads. The specifications for solder deposition with irregular stencil apertures need to be adjusted. Originality/value – To address the arbitrariness of existing industry practice, this study was a joint effort with a Taiwan-based electronics manufacturing service company. Real data were taken from a mass production environment and inferences were then made based on a statistical analysis

Publisher: National Taipei University

Conquering SMT Stencil Printing Challenges with Today's Miniature Components

Jun 12, 2023 | Robert F. Dervaes, Jeff Poulos, Scott Williams

The technological advancement of component and PCB technology from through-hole to surface mount (SMT) is a major factor in the miniaturization of today's electronics. Smaller and smaller component sizes and more densely packed PCBs lead to more powerful designs in much smaller product packages. With advancement, however, comes a new set of challenges in building these smaller, more complex assemblies. This is the challenge original equipment manufacturers (OEM) and contract manufacturers (CM) face today....

Publisher: Fine Line Stencil, Inc.

Additive Manufacturing Technologies

Jun 02, 2023 | K. Srinivasulu Reddy & Solomon Dufera

Additive manufacturing (AM) is a latest technology that could improve manufacturing process by building up thin layers of materials from digitized three-dimensional (3D) designs virtually constructed using advanced CAD software. This technique affords the creation of new types of object with unique material properties. But while AM is widely billed as ‘the next industrial revolution’, in reality there are still significant hurdles for successful commercialisation of the technologies. This paper aims to provide a comprehensive review of literature, technologies and manufacturing practices on modern Additive Manufacturing.

Publisher: Adama Science and Technology University

Combining 3D Printing And Printable Electronics

Jun 02, 2023 | John Sarik, James Scott, Alex Butler, Steve Hodges, Nicolas Villar

A platform that enables the integration of conductive traces and printed three dimensional mechanical structures has been developed. We discuss the development of the platform and address issues that arise when combining 3D printing and printable electronics. We demonstrate a rapid prototyped three dimensional conductive trace and propose future applications for the platform.

Publisher: Columbia University

3-D Printed Electronics Additively Manufactured Electronics (AME)

Jun 02, 2023 | Nano Dimension

This presentation of Nano Dimension Ltd. (the"Company") contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act and other securities laws. Words such as "expects," "anticipates, " "intends, " "plans, " "believes, " "seeks, " "estimates" and similar expressions or variations of such words are intended to identify forward-looking statements. For example, the Company is using forward-looking statements when it discuss the potential of its products, strategic growth plan, its business plan and investment plans, the size fits addressable market, market growth, and expected recurring revenue growth. Forward-looking statements are no historical facts, and are based upon management's current expectations, beliefs and projections, many of which, by their nature, are inherently uncertain. Such expectations, beliefs and projections are expressed in good faith. However, there can be assurance that management's expectations, beliefs and projections will be achieved, and actual results may differ materially from what is expressed in or indicated by the forward-looking statements. Forward-looking statements are subject to risks and uncertainties that could cause actual performance or results to differ materially from those expressed in the forward-looking statements. For a more detailed description of the risks and uncertainties affecting the Company, reference is made to the Company's reports filed from time to time with the Securities and Exchange Commission ("SEC"), including, but not limited to, the risks detailed in the Company's annual report for the year ended December 31st, 2020, filed with the SEC. Forward-looking statements speak only as of the date the statements are made. The Company assumes no obligation to update forward-looking statements to reflect actual results, subsequent events or circumstances, changes in assumptions or changes in other factors affecting forward-looking information except to the extent required by applicable securities laws. If the Company does update one or more forward-looking statements, no inference should be drawn that the Company will make additional updates with respect thereto or with respect to other forward-looking statements....

Publisher: Nano Dimension

Conformal Coating of Thin Polymer Electrolyte Layer on Nanostructured Electrode Materials for Three-Dimensional Battery Applications

Jun 02, 2023 | Sanketh R. Gowda, Arava Leela Mohana Reddy, Manikoth M. Shaijumon, Xiaobo Zhan, Lijie Ci, and Pulickel M. Ajayan

Various three-dimensional (3D) battery architectures have been proposed to address effective power delivery in micro/ nanoscale devices and for increasing the stored energy per electrode footprint area. One step toward obtaining 3D configurations in batteries is the formation of core-shell nanowires that combines electrode and electrolyte materials. One of the major challenges however in creating such architectures has been the coating of conformal thin nanolayers of polymer electrolytes around nanostructured electrodes. Here we show conformal coatings of 25-30 nm poly(methyl methacralate) electrolyte layers around individual Ni-Sn nanowires used as anodes for Li ion battery. This configuration shows high discharge capacity and excellent capacity retention even at high rates over extended cycling, allowing for scalable increase in areal capacity with electrode thickness. Our results demonstrate conformal nanoscale anode-electrolyte architectures for an efficient Li ion battery system.

Publisher: Rice University

3D Printed Electronics

Jun 02, 2023 | M. Bowa, M. E. Dean, and R.D. Horn

Additive manufacturing is revolutionizing the way we build and produce a plethora of products spanning many industries. It has shown strong potential in reduced energy use, sustainability and cost effectiveness. Exploring avenues that this technology can be utilized is key to improve productivity and efficiencies in various applications including electronic systems and devices manufacturing. Electronic systems and sub-systems are built using a variety of material and processes, which require a large carbon footprint, significant waste material and high production time. We propose the application of 3D printing technology to support an integrative process for combining circuit board fabrication, solder mask process, electronic component pick and place and enclosure manufacturing. The integration of these separate processes into a single high efficiency additive manufacturing process will yield significant savings in energy use, carbon footprint, waste product and production time and cost.

Publisher: University of Tennessee

A Manufacturing Process For An Energy Storage Device Using 3D Printing

Jun 02, 2023 | Anan Tanwilaisiri, Ruirong Zhang, Yanmeng Xu, David Harrison and John Fyson

3D printing has been widely applied in the development of prototypes. The main advantage of this process is that the objects or products can be viewed in three dimensions on a computer display and a 3D sample can be created before committing to a large production run. There are various 3D printing technologies that are capable of manufacturing metal, ceramic, plastic substrate and paste objects. Recently several research groups have focused on the fabrication freedom of 3D printing for different purposes including freeform manufacturing of electrochemical devices but this use is still limited. This paper describes a manufacturing process for electrochemical supercapacitors using the combination of the two techniques of 3D printing which are Fused Deposition Modelling (FDM) and a Paste Extrusion system. The method relies on creating a frame for the energy storage device, i.e. supercapacitor, by the FDM 3D printer and then depositing the conductive layers and electrodes of the supercapacitor using Paste Extrusion system. A 3D supercapacitor has been made and evaluated in this study.

Publisher: Brunel University London

Additive Manufacturing – A Sustainable Manufacturing Route

Jun 02, 2023 | Domnita Fratila and Horatiu Rotaru

Additive Manufacturing (AM) technologies allow developing and manufacturing very complex shaped parts and functional products with a high level of customization, being a great alternative to Traditional Manufacturing (TM) methods like injection molding, die-casting or machining. Due to the importance of cleaner production in the field of manufacturing processes, sustainability of AM processes needs to be assessed in order to make easier its acceptance and implementation in the industry. Furthermore, the manufacturers can improve their competitiveness and profitability by considering the ecological aspects during the manufacturing step of a product. This paper gives a survey on sustainability issues related to AM.

Publisher: Technical University of Cluj-Napoca

3D-Printing And Advanced Manufacturing For Electronics

Jun 02, 2023 | Alejandro H. Espera Jr., John Ryan C. Dizon, Qiyi Chen, Rigoberto C. Advincula

Printed electronics currently holds a significant share in the electronics fabrication market due to advantages in high-throughput production and customizability in terms of material support and system process. The printing of traces and interconnects, passive and active components such as resistors, capacitors, inductors, and application-specific electronic devices, have been a growing focus of research in the area of additive manufacturing. Adaptation of new 3D-printing technologies and manufacturing methods, specifically for printed electronics, are potentially transformative in flexible electronics, wireless communications, efficient batteries, solid-state display technologies, etc. Other than printing new and reactive functional electronic materials, the functionalization of the printing substrates with unusual geometries apart from the conventional planar circuit boards will be a challenge. Building the substrate, printing the conductive tracks, pick-and-placing or embedding the electronic components, and interconnecting them, are fundamental fabrication protocols new 3D-printing systems should adopt for a more integrated fabrication. Moreover, designers and manufacturers of such systems will play an important role in scaling 3D-printed electronics from prototyping to high-throughput mass production. This review gives a groundwork for such understanding, defining methods and protocols, reviewing various 3D-printing methods, and describing the state-of- the-art in 3D-printed electronics and their future growth.

Publisher: Case Western Reserve University

3D Printing Electronic Components And Circuits With Conductive Thermoplastic Filament

Jun 02, 2023 | Patrick F. Flowers, Christopher Reyes, Shengrong Ye, Myung Jun Kim, Benjamin J. Wiley

This work examines the use of dual-material fused filament fabrication for 3D printing electronic components
and circuits with conductive thermoplastic filaments. The resistivity of traces printed from
conductive thermoplastic filaments made with carbon-black, graphene, and copper as conductive fillers
was found to be 12, 0.78, and 0.014 ohm cm, respectively, enabling the creation of resistors with values
spanning 3 orders of magnitude. The carbon black and graphene filaments were brittle and fractured
easily, but the copper-based filament could be bent at least 500 times with little change in its resistance.
Impedance measurements made on the thermoplastic filaments demonstrate that the copper-based filament
had an impedance similar to a copper PCB trace at frequencies greater than 1 MHz. Dual material
3D printing was used to fabricate a variety of inductors and capacitors with properties that could be
predictably tuned by modifying either the geometry of the components, or the materials used to fabricate
the components. These resistors, capacitors, and inductors were combined to create a fully 3D
printed high-pass filter with properties comparable to its conventional counterparts. The relatively low
impedance of the copper-based filament enabled its use for 3D printing of a receiver coil for wireless
power transfer. We also demonstrate the ability to embed and connect surface mounted components in
3D printed objects with a low-cost ($1000 in parts), open source dual-material 3D printer. This work thus
demonstrates the potential for FFF 3D printing to create complex, three-dimensional circuits composed
of either embedded or fully-printed electronic components.

Publisher: Duke University

Preparation and Properties of Graphite/Epoxy Resin Conductive Composites

May 30, 2023 | Shan-Shan Yao, Di Jiang, Qi-Zhong Zhang, Xin-Xin Wang

Graphite / epoxy resin conductive composites were prepared by mixing and molding process, using graphite and epoxy resin as raw materials, filling carbon fiber cloth and mixing a small amount of metal powder. We investigated effects on the different ratio of graphite raw materials and the amount of carbon fiber cloth and different metal powder on the resistance and bending strength of graphite / epoxy resin conductive composites. The optimum ratio of raw materials was determined by the experiment. The results showed that the electrical and mechanical properties of the composites were good when the ratio of the two kinds of graphite was 1:1, filling two layers of carbon fiber cloth and the content of aluminum powder was 1%. The resistivity was up to 0.0800 ohm cm, and the bending strength was up to 47.32MPa.

Publisher: Jilin Institute of Chemical Technology

Improvement of the Electrical-Mechanical Performance of Epoxy/Graphite Composites Based on the Effects of Particle Size and Curing Conditions

May 30, 2023 | Hendra Suherman , Radwan Dweiri, Abu Bakar Sulong, Mohd Yusuf Zakaria and Yovial Mahyoedin

This study aims to improve the electrical-mechanical performance of traditional epoxy/graphite composites for engineering applications. The improvement in the properties of these composites depended on the incorporation of different sizes of graphite particles of the same type and controlling their curing process conditions. The thermal properties andmicrostructural changeswere also characterized. A maximum in-plane electrical conductivity value of approximately 23 S/cm was reported for composites containing 80 wt.% G with a particle size of 150 _m. The effect of combining large and small G particles increased this value to approximately 32 S/cm by replacing the large particle size with 10 wt.% smaller particles (75 _m). A further increase in the electrical conductivity to approximately 50 S/cmwas achieved due to the increase in curing temperature and time. Increasing the curing temperature or time also had a crucial role in improving the tensile strength of the composites and a tensile strength of ~19MPa was reported using a system of multiple filler particle sizes processed at the highest curing temperature and time compared to ~9 MPa for epoxy/G150 at 80 wt.%. TGA analysis showed that the composites are thermally stable, and stability was improved by the addition of filler to the resin. A slight difference in the degraded weights and the glass transition temperatures between composites of different multiple filler particle sizes was also observed from the TGA and DSC results.

Publisher: Universitas Bung Hatta

Improved Heat-Spreading Properties Of Fluorinated Graphite/ Epoxy Film

May 30, 2023 | Kyung Hoon Kim, Jeong-In Han, Da-Hee Kang, and Young-Seak Lee

The use of electronic devices has rapidly increased, and such devices are required to be smaller, thinner, lighter, and with higher energy densities than ever before. These requirements can result in the generation of additional heat during device operation, and this heat has detrimental effects on performance, stability, running rate, and lifespan. For instance, if the temperature of an electronic device increases by 2oC when the operating temperature is higher than the stable operating temperature, the stability of the device will be reduced by 10% [1-3]. Thus, the additional heat that such devices generate must be spread to the surrounding environment via heat sinks, coatings, or films with high thermal conductivity.

The use of coatings and films is an appropriate approach for improving the heat spread in electronic devices, particularly as these devices become lighter, smaller, and thinner. Such coatings and films are typically based on polymers such as epoxy, acryl, and polyurethane. Due to the low thermal conductivity of these polymers, it is difficult to use this approach to achieve effective heat spreading. To solve this problem, a great deal of research has addressed the addition of fillers with high thermal conductivity, such as aluminum nitride [4,5], silica (SiO2), alumina (Al2O3), boron nitride [1,6,7], graphite [8], expanded graphite (EG) [9-11], carbon nanotubes (CNTs) [11-13], graphene [9,14,15], and graphene oxide (GO) to polymer-based coatings. Recently, carbon-based materials such as graphite, EG, CNTs, graphene, and GO have been widely investigated because of their low density and high thermal conductivity. However, CNTs and graphene are not appropriate for large-scale applications due to their high production cost and complex processing. In addition, fillers with poor dispersive stability aggregate in coatings form voids, resulting in the degradation of thermal conductivity [16,17]. In this study, anionic fluorine functional groups are introduced into a graphite surface via direct fluorination to increase dispersive stability by generating electrostatic repulsion. We expect the enhanced dispersive stability of the modified graphite to lead to the formation of fewer voids, resulting in improved thermal conductivity of the prepared heat-spreading film.

Publisher: Chungnam National University

Electro-Conductive Resins Filled With Graphite For Casting Applications

May 30, 2023 | Igor Novak, Igor Krupa

Electro-conductive resins, convenient for casting and coating applications were investigated in this paper. Electrical conductivity of epoxy and polyurethane resins, filled with two different grades of synthetic graphite (different average size) was studied. It was found that all the investigated composites became electro-conductive when filled with 22-vol% of the filler. The impact strength of epoxy and polyurethane resins filled with graphite was also investigated. A decrease in impact strength with an increase in filler content was observed in all cases. The highest values of impact strength were found for polyurethane/graphite KS 6 composites. The strength of adhesion of the filled resins to aluminum was also determined. A decrease in the strength of adhesive joints to aluminum foils with an increase in filler content was observed in all cases. The strongest adhesive joints were found for the epoxy/graphite KS 6 composites.

Publisher: Slovak Academy of Sciences

Recent Progress On Thermal Conductivity Of Graphene Filled Epoxy Composites

May 30, 2023 | Ruicong Lv, Yanjuan Ren, Haichang Guo, Shulin Bai

With the rapid development of the electronic industry, the requirements for packaging materials with high thermal conductivity (TC) are getting higher and higher. Epoxy is widely used as package material for electronic package applications. But it's intrinsic TC can't meets the increasing demands. Adding high TC graphene into epoxy matrix is a proper way to reinforce epoxy composites. This review focuses on the filler modification, preparation process and thermal properties of graphene-filled epoxy resin composites. Different ways of covalent and non-covalent modification methods are discussed. The various kinds of graphene coating layer are also summarized. Then we analysis the hybrid filler system in epoxy composite. We hope this review will provide guidance for the development and application of graphene-filled epoxy resin composites.

Publisher: Peking University

在DPC陶瓷基板上如何做碳油厚膜电阻

May 23, 2023 | 斯利通

在DPC陶瓷基板上如何做碳油厚膜电阻...

Publisher: Folysky Technology(Wuhan)Co.,Ltd

QUANTIFYING THE IMPROVEMENTS IN THE SOLDER PASTE PRINTING PROCESS FROM STENCIL NANOCOATINGS AND ENGINEERED UNDER WIPE SOLVENTS

May 22, 2023 | Chrys Shea, Mike Bixenman, T.C. Loy, Debbie Carboni, Brook Sandy-Smith, Greg Wade, Ray Whittier, Joe Perault, Eric Hanson

Over the past several years, much research has been performed and published on the benefits of stencil nano-coatings and solvent under wipes. The process improvements are evident and well-documented in terms of higher print and end-of-line yields, in improved print volume repeatability, in extended under wipe intervals, and in photographs of the stencil's PCB-seating surface under both white and UV light. But quantifying the benefits using automated Solder Paste Inspection (SPI) methods has been elusive at best. SPI results using these process enhancements typically reveal slightly lower paste transfer efficiencies and less variation in print volumes to indicate crisper print definition. However, the improvements in volume data do not fully account for the overall improvements noted elsewhere in both research and in production....

Publisher: KYZEN Corporation

Nanocoating and SMT Stencils

May 22, 2023 | Tecan

With a thickness of no more than 1-100 nanometers, nanocoatings are ultra-thin layers or chemical structures that are applied to surfaces by a variety of methods and applied to a wide range of substrates and chemically bond with non-porous surfaces. To put this in perspective, consider the thickness of paint used in the automotive industry of which is typically 125 microns or 125,000 nanometers.
While they can be one molecule thick, multiple molecular layers can be built up to deliver a particular chemical or physical property to a surface such as water-resistance (hydrophobic) and oil-resistance (oleophobic).

Publisher: tecan

Nanocoatings Webinar & NanoClear® Stencil Treatment

May 22, 2023 | Edward Hughes, ChrysShea

Agenda Overview Independent Testing & Studies-Print studies -Understencil Wipe studies-Durability Testing-Ongoing Studies NanoClear Product Information NanocoatingsComparison Summary Questions...

Publisher: Aculon

NanoClear Coated Stencils

May 22, 2023 | DEK Engineered Products

Our customers' issues • Apertures are getting smaller • Paste does not release as well • Contaminates the bottom of the stencil • Increases defects / reduces yield  Insufficient solder  Bridging  Solder balls on surface of PCB  Flux residue • Requires more frequent cleaning • Reduced efficiency (wasted time) • Increased use of consumables (cost)  USC fabric (use "cheap" fabric to reduce cost)  Lint creates more defects  Cleaning chemistries (use IPA to reduce cost)  IPA breaks down flux and can create more defects...

Publisher: ASM Assembly Systems (DEK)

CHANGING THE RULES OF STENCIL DESIGN

May 22, 2023 | Tony Lentz

Nano-coatings are applied to solder paste stencils with the intent of improving the solder paste printing process. Do they really make a noticeable improvement? The effect of Nano-coatings on solder paste print performance was investigated. Transfer efficiencies were studied across aperture sizes ranging from 0.30 to 0.80 area ratio. Also investigated were the effects of Nano-coatings on transfer efficiencies of tin-lead, lead-free, water soluble, no-clean, and type 3, 4, and 5 solder pastes. Solder paste print performance for each Nano-coating was summarized with respect to all of these variables....

Publisher: FCT ASSEMBLY, INC.

Several ceramic materials are commonly used for the ceramic PCB

May 10, 2023 | 斯利通

Several ceramic materials are commonly used for the ceramic PCB...

Publisher: Folysky Technology(Wuhan)Co.,Ltd

Several ceramic materials are commonly used for the ceramic PCB

May 10, 2023 | 斯利通

Several ceramic materials are commonly used for the ceramic PCB...

Publisher: Folysky Technology(Wuhan)Co.,Ltd

Zirconia ceramic PCB, for applications in the field of microwave communication

May 10, 2023 | 斯利通

Zirconia ceramic PCB, for applications in the field of microwave communication...

Publisher: Folysky Technology(Wuhan)Co.,Ltd

The role that sapphire ceramic PCB play in MEMSdevices

May 10, 2023 | 斯利通

DPC (DirectPlatingCopper) thin film process is a method of prepare copper film using magnetron sputtering technology. This process is a process in which the copper target with the target material is placed in a true cavity chamber, and plasma is generated on the copper target surface by magnetron sputtering technology. The ions in the plasma are bombarded on the surface of the target, which is sputtered into fine particles and deposited on the substrate to form a copper film....

Publisher: Folysky Technology(Wuhan)Co.,Ltd

Electronic Assembly Misprint Cleaning Advancements

May 07, 2023 | Mike Bixenman, Dirk Ellis, Jody Saultz, Eric Becker, Greg Calvo & Jim Morris

Misprint Circuit Assemblies ■ Cleaning misprints is a production gap ■ Commonly cleaned in stencil cleaning equipment ■ Stencil Cleaning equipment allows for the collection and filtration of wet solder paste ■ Stencil Cleaning equipment short comings + Inability to clean B-Side misprints + Poor rinse quality...

Publisher: ITW EAE

First Post - Tell me about your company!

May 05, 2023 | RW

ETC is an OEM manufacturer out of the US.  Our SMT department is high mix, low volume.  We utilize Mycronic mahcines and have production five lines currently; some single machines, others in sequence.  Our maturity with this manufacturing process is about 20 years.  Our products are populated with my100's, 200's, and 300's.

• ~1 million PCAs
  • ~100 million components
    • 700+ unique materials
      • 2,500+ unique smt components

Publisher: ETC, INC.

IMPACT OF 0201 COMPONENTS ON CURRENT MANUFACTURING SYSTEMS

May 02, 2023 | Andrew Butterfield, Mark Guilford, Kevin Pieper

The use of 0201 components in consumer products offers a major competitive advantage over other products since they allow significant design miniaturization. This leads to either smaller products or allows more features integrated into the same package size. One of the critical aspects of having the capability of placing 0201 components in any product is the ability of the manufacturing equipment to handle such small components. Many process studies have been completed by manufacturers and equipment suppliers and have shown that tight process windows are required. The current process control for 0402 components is CpK > 1.5 with a 150μm specification window. For 0201 components, the minimum requirement is CpK > 2.0 with a 100μm specification window. The spec window may need to be reduced down to 75μm if the controls for high volume manufacturing are insufficient. Also directly impacting the placement quality is the ability to apply sufficient solder consistently to the board. The goal is to maintain current printing practices, but the effect of powder size will be examined. This paper will evaluate the impact of placement accuracy and solder powder size on 0201 manufacturing quality....

Publisher: Motorola Mobility LLC.

Board Design and Assembly Process Evaluation for 0201 Components on PCBs

May 02, 2023 | Mei Wang, Dr. Dongkai Shangguan, David Geiger, Kazu Nakajima, CC. Ho, and Sammy Yi

As 0402 has become a common package for printed circuit board (PCB) assembly, research and development on mounting 0201 components is emerging as an important topic in the field of surface mount technology for PWB miniaturization. In this study, a test vehicle for 0201 packages was designed to investigate board design and assembly issues. Design of Experiment (DOE) was utilized, using the test vehicle, to explore the influence of key parameters in pad design, printing, pick-andplace, and reflow on the assembly process. These key parameters include printing parameters, mounting height or placement pressure, reflow ramping rate, soak time and peak temperature. The pad designs consist of rectangular pad shape, round pad shape and home-based pad shape. For each pad design, several different aperture openings on the stencil were included. The performance parameters from this experiment include solder paste height, solder paste volume and the number of post-reflow defects. By analyzing the DOE results, optimized pad designs and assembly process parameters were determined....

Publisher: Flextronics International

PCB Design Optimization of 0201 Packages for Assembly Processes

May 02, 2023 | Mei Wang, Dr. Dongkai Shangguan, David Geiger, Fredrik Mattsson and Sammy Yi

The demand for 0201 components in consumer products will increase sharply over the next few years due to the need for miniaturization. It is predicted that over 20 billion 0201 components will be used in more than one billion cell phones worldwide by the year 2003. Therefore, research and development on 0201 assembly is becoming a very hot topic. The first step to achieve a successful assembly process is to obtain a good PCB design for 0201 packages. This paper presents the data and criteria of PCB design for 0201 packages, including the pad design for 0201 components, and the minimum pad spacing or component clearance between 0201 components or between 0201 and other components. A systematic study on pad design and pad spacing was undertaken, using two test vehicles and three Design of Experiments (DOEs). In the first DOE, 2 out of 18 types of 0201 pad designs were selected based on process yield. The second DOE was focused on pad spacing, including 10mil, 8mil, 6mil and 4mil. The third experiment was final optimization, using two types of optimized pad designs with 10mil, 8mil and 6mil pad spacing. Through the above experiments, the design guideline for PCB layout for 0201 packages and the assembly process capability are identified....

Publisher: Flextronics International

RULES FOR WORKING WITH 0201s AND OTHER SMALL PARTS

May 02, 2023 | Advanced Assembly, LLC

Surface-mount PCB components are smaller than their lead-based counterparts and provide a radically higher component density. They are available in a variety of shapes and sizes designated by a series of standardized codes curated by the electronics industry. Of these PCB components, the 0201-sized are the smallest, measuring 0.024 x 0.012 in. (0.6 x 0.3 mm) – that's 70% smaller than the previous 0402 level! The 0201 components are designed to improve reliability in space-constrained applications such as portable electronics like smartphones, tablets, robotics and digital cameras, but require delicate handling during the assembly process....

Publisher: Advanced Assembly, LLC.

RULES FOR WORKING WITH 0201s AND OTHER SMALL PARTS

May 02, 2023 | Advanced Assembly, LLC

Surface-mount PCB components are smaller than their lead-based counterparts and provide a radically higher component density. They are available in a variety of shapes and sizes designated by a series of standardized codes curated by the electronics industry. Of these PCB components, the 0201-sized are the smallest, measuring 0.024 x 0.012 in. (0.6 x 0.3 mm) – that's 70% smaller than the previous 0402 level! The 0201 components are designed to improve reliability in space-constrained applications such as portable electronics like smartphones, tablets, robotics and digital cameras, but require delicate handling during the assembly process. Given the miniaturized dimensions of an 0201 package, it is crucial that the mounting process abide by a series of guidelines regarding the design of the PCB mounting pads and solderable metallization, PCB circuit trace width, solder paste selection, package placement and overages, solder paste reflow, solder stencil screening, and final inspection. It's advisable that one review this information when procuring the services of a PCB assembler....

Publisher: Advanced Assembly, LLC.

Neo Station: Revolutionize PCB assembly

Apr 29, 2023 | Neotel Technology

The world of electronics is continuously evolving, and the need for faster, more efficient, and more precise assembly of printed circuit boards (PCBs) has become paramount. Neotel Technology's latest innovation, the Neo Station, offers a comprehensive solution for PCB assembly that combines state-of-the-art features with unparalleled ease of use. This document outlines the key features and benefits of the Neo Station, a groundbreaking tool that is set to revolutionize the electronics industry....

Publisher: Neotel Technology Co., Ltd

PWB Contamination & Reliability DOE

Apr 25, 2023 | Michael R. Weekes

This report hopes to achieve several goals: 1. Determine the link between bare PWB contamination, soldered assembly contamination and long-term product reliability. 2. Establish measurable limits for bare PWB cleanliness as well as process control limits for both an aqueous as well as a water-soluble soldering process. 3. Determine whether there is any correlation between common, industry-accepted rose/modified rose (omegameter/ionograph type) testing and long term product reliability. 4. Determine the effect PWB plating finish (HASL, Immersion Silver and Cu OSP) has on both bare PWB contamination as well as soldered assembly in a no clean and water soluble process. 5. Determine whether there is a link between percentage of saponifier used to wash soldered assemblies and long-term reliability. 6. Establish a more cost-effective test for manufacturers to use as a process-monitoring tool.

Publisher: John Deere Electronic Solutions

WHY test for Ionic Contamination?

Apr 17, 2023 | Specialty Coating Systems

Ionic contamination is a leading cause in the degradation and corrosion of electronic assemblies, leading to lifetime limitation and field failure (Fig. 1). Ionic residue comes from a variety of sources shown in Fig. 2 opposite: Examples of ionic contaminants: * Anions * Cations * Weak Organic Acid...

Publisher: Specialty Coating Systems

The Relationship Between Cleanliness and Reliability/Durability

Apr 17, 2023 | Debbie Carboni

Outline/Agenda * Introduction of Ionics and ROSE * Evolution in technology * Rev H in the IPC-J-STD-001 * Real World Case Study * Conclusions...

Publisher: KYZEN Corporation