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1 – 10 of over 3000
Article
Publication date: 5 June 2007

Tero Peltola and Pauliina Mansikkamäki

The paper aims to deal with the benefits and challenges of 3D integration of electronics and mechanics as well as the special requirements in designing a system.

Abstract

Purpose

The paper aims to deal with the benefits and challenges of 3D integration of electronics and mechanics as well as the special requirements in designing a system.

Design/methodology/approach

Three‐dimensional integration technology has been enabled by innovations in thermoplastic printed circuit board (PCB) materials and novel system integration. Furthermore, the integration of electronics and mechanics helps manage product creation, as design phases must be integrated and teamwork well organized. A multidisciplinary approach is another must in marketing technology, because any decision to incorporate an integrative technology in a product must be based on an understanding of the many forms of expertise involved in creating a product.

Findings

With a unique copper pattern for each 3D shape, inconvenient distortions can be controlled, as dedicated copper patterns enable designers to make efficient use of formable multilayer structures and advance an extra step in freedom of design. Findings are based on a working demonstrator.

Research limitations/implications

Even if 3D multilayer design now lacks dedicated tools, software is likely to evolve to include all necessary functions.

Practical implications

Forming a multilayer PCB enables designers to free their imagination and to take advantage of numerous possibilities, including even futuristic shapes.

Originality/value

Three‐dimensional integration offers great potential for product design, although by definition and in terms of production technology 3D integration is an incremental change.

Details

Journal of Engineering, Design and Technology, vol. 5 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 January 1994

M. Alexander, K. Srihari and C.R. Emerson

A product's design influences its manufacturing process and the associated costs. Consequently, design engineers need to review their designs from a manufacturing…

Abstract

A product's design influences its manufacturing process and the associated costs. Consequently, design engineers need to review their designs from a manufacturing perspective. While ‘Design For Manufacturing’ (DFM) tools often identify the manufacturing problems associated with a design, they would be more effective if these problems could be represented to the designer in terms of a cost value. This research developed a cost estimation tool for the designer in the surface mount printed circuit board (PCB) domain by integrating computer aided design, computer aided process planning (CAPP) and cost estimation techniques using a knowledge based framework. The cost estimation can be done in two design stages. First, an initial approximation of the manufacturing cost can be obtained using information such as the component mix, type of substrate and the size of board. After the detailed design of the PCB has been developed, a more accurate PCB assembly cost can be obtained using computer aided design (CAD) data. Both cost determination strategies would require the generation of a macro‐process plan. The cost advisor considers tangible and intangible factors. This cost advisor and the DFM environment have been developed using C ++ and object oriented programming constructs under the MS Windows operating system.

Details

Circuit World, vol. 20 no. 2
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 2 February 2015

M.S. Abdul Aziz, M.Z. Abdullah and C.Y. Khor

This paper aims to investigate the thermal fluid–structure interactions (FSIs) of printed circuit boards (PCBs) at different component configurations during the wave…

Abstract

Purpose

This paper aims to investigate the thermal fluid–structure interactions (FSIs) of printed circuit boards (PCBs) at different component configurations during the wave soldering process and experimental validation.

Design/methodology/approach

The thermally induced displacement and stress on the PCB and its components are the foci of this study. Finite volume solver FLUENT and finite element solver ABAQUS, coupled with a mesh-based parallel code coupling interface, were utilized to perform the analysis. A sound card PCB (138 × 85 × 1.5 mm3), consisting of a transistor, diode, capacitor, connector and integrated circuit package, was built and meshed by using computational fluid dynamics pre-processing software. The volume of fluid technique with the second-order upwind scheme was applied to track the molten solder. C language was utilized to write the user-defined functions of the thermal profile. The structural solver analyzed the temperature distribution, displacement and stress of the PCB and its components. The predicted temperature was validated by the experimental results.

Findings

Different PCB component configurations resulted in different temperature distributions, thermally induced stresses and displacements to the PCB and its components. Results show that PCB component configurations significantly influence the PCB and yield unfavorable deformation and stress.

Practical implications

This study provides PCB designers with a profound understanding of the thermal FSI phenomenon of the process control during wave soldering in the microelectronics industry.

Originality/value

This study provides useful guidelines and references by extending the understanding on the thermal FSI behavior of molten solder for PCBs. This study also explores the behaviors and influences of PCB components at different configurations during the wave soldering process.

Details

Soldering & Surface Mount Technology, vol. 27 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 6 January 2022

Lijuan Huang, Zhenghu Zhu, Hiarui Wu and Xu Long

As the solution to improve fatigue life and mechanical reliability of packaging structure, the material selection in PCB stack-up and partitioning design on PCB to…

Abstract

Purpose

As the solution to improve fatigue life and mechanical reliability of packaging structure, the material selection in PCB stack-up and partitioning design on PCB to eliminate the electromagnetic interference by keeping all circuit functions separate are suggested to be optimized from the mechanical stress point of view.

Design/methodology/approach

The present paper investigated the effect of RO4350B and RT5880 printed circuit board (PCB) laminates on fatigue life of the QFN (quad flat no-lead) packaging structure for high-frequency applications. During accelerated thermal cycling between −50 °C and 100 °C, the mismatched coefficients of thermal expansion (CTE) between packaging and PCB materials, initial PCB warping deformation and locally concentrated stress states significantly affected the fatigue life of the packaging structure. The intermetallics layer and mechanical strength of solder joints were examined to ensure the satisfactorily soldering quality prior to the thermal cycling process. The failure mechanism was investigated by the metallographic observations using a scanning electron microscope.

Findings

Typical fatigue behavior was revealed by grain coarsening due to cyclic stress, while at critical locations of packaging structures, the crack propagations were confirmed to be accompanied with coarsened grains by dye penetration tests. It is confirmed that the cyclic stress induced fatigue deformation is dominant in the deformation history of both PCB laminates. Due to the greater CTE differences in the RT5880 PCB laminate with those of the packaging materials, the thermally induced strains among different layered materials were more mismatched and led to the initiation and propagation of fatigue cracks in solder joints subjected to more severe stress states.

Originality/value

In addition to the electrical insulation and thermal dissipation, electronic packaging structures play a key role in mechanical connections between IC chips and PCB.

Details

Multidiscipline Modeling in Materials and Structures, vol. 18 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 7 September 2015

Soonwan Chung and Jae B. Kwak

This paper aims to develop an estimation tool for warpage behavior of slim printed circuit board (PCB) array while soldering with electronic components by using finite…

Abstract

Purpose

This paper aims to develop an estimation tool for warpage behavior of slim printed circuit board (PCB) array while soldering with electronic components by using finite element method. One of the essential requirements for handheld devices, such as smart phone, digital camera, and Note-PC, is the slim design to satisfy the customers’ desires. Accordingly, the printed circuit board (PCB) should be also thinner for a slim appearance, which would result in decreasing the PCB’s bending stiffness. This means that PCB deforms severely during the reflow (soldering) process where the peak temperature goes up to 250°C. Therefore, it is important to estimate PCB deformation at a high temperature for thermo-mechanical quality/reliability after reflow process.

Design/methodology/approach

A numerical simulation technique was devised and customized to accurately estimate the behavior of a thin printed board assembly (PBA) during reflow by considering all components, including PCB, microelectronic packages and solder interconnects.

Findings

By applying appropriate constraints and boundary conditions, it was found that PBA’s warpage can be accurately predicted during the reflow process. The results were also validated by warpage measurement, which showed a fairly good agreement with one and another.

Research limitations/implications

For research limitations, there are many assumptions regarding numerical modeling. That is, the viscoplastic material property of solder ball is ignored, the reflow profile is simplified and the accurate heat capacity is not considered. Furthermore, the residual stress within the PCB, generated at PCB manufacturing process, is not included in this paper.

Practical implications

This paper shows how to calculate PBA warpage during the reflow process as accurately as possible. This methodology helps a PCB designer and surface-mount technology (SMT) process manager to predict a PBA warpage issue and modify PCB design before PCB real fabrication. Practically, this modeling and simulation process can be easily performed by using a graphical user interface (GUI) module, so that the engineer can handle an issue by inputting some numbers and clicking some buttons.

Social implications

In a common sense manner, a numerical simulation method can decrease time and cost in manufacturing real samples. This PCB warpage method can also decrease product development duration and produce a new product earlier. Furthermore, PCB is a common component in all the electronic devices. So, this PCB warpage method can have various applications.

Originality/value

Because of an economic advantage, the development of a numerical simulation tool for estimating the thin PBA warpage behaviour during reflow process was attempted. The developed tool contains the features of detailed modeling for electronic components and contact boundary conditions of the supporting rails in the reflow oven.

Details

Soldering & Surface Mount Technology, vol. 27 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 1 January 2014

Andrea M. Maric, Goran J. Radosavljevic, Walter Smetana and Ljiljana D. Zivanov

This paper presents performance comparison of RF inductors with the same lateral geometry applying different substrate configurations. The purpose of presented research is…

Abstract

Purpose

This paper presents performance comparison of RF inductors with the same lateral geometry applying different substrate configurations. The purpose of presented research is to demonstrate and verify some advantages of low temperature co-fired ceramic (LTCC) technology in comparison to printed circuit board (PCB) technology based on the performance analysis of presented inductors in lower RF range.

Design/methodology/approach

The presented inductors are meander structures fabricated in LTCC and PCB technology, with same line width and outer dimensions. Performance analysis of all configurations is based on measurement results and numerical simulations. Advantage of LTCC technology is demonstrated by application of substrate pattering in order to maintain and/or improve expected inductor performances.

Findings

As expected, obtained results for the inductor with an air-gap show increase of the quality factor over 30 percent and widening of the operating frequency range by 50 percent when compared with the same LTCC structure without a gap. But what is more important the inductor with air-gap embedded inside LTCC stack maintains efficiency when compared to PCB inductor. This fact offers possibility of integration good quality components inside LTCC stack and reduction of used chip space.

Originality/value

Advantages of LTCC with respect to PCB design are demonstrated by efficiency increase of the proposed inductor configurations by means of design optimization relying on substrate pattering and incensement of the packaging density by embedding inductors. The presented findings are verified through consistency of measurement results and simulated data.

Details

Microelectronics International, vol. 31 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 5 April 2013

Chien‐Yi Huang and Yueh‐Hsun Lin

The purpose of this paper is to employ data mining as a new diagnosing scheme for investigating void formation to the thermal pad in quad flat non‐lead (QFN) assembly…

Abstract

Purpose

The purpose of this paper is to employ data mining as a new diagnosing scheme for investigating void formation to the thermal pad in quad flat non‐lead (QFN) assembly. Occurrences of voiding in various scenarios of component design, materials selection and manufacturing process are analyzed.

Design/methodology/approach

This research investigates the process yield of a PCB assembly for a handheld device in the electronics manufacturing industry using the chi‐square automatic interaction detection (CHAID) algorithm and chi‐square test. Practical data generated by an X‐ray apparatus from the shop floor are collected. The critical attributes to the void formation (in the solder joint) of the QFN component are identified.

Findings

Stocking the PCB material beyond ten days may increase the level of voiding by 1%. Using PCB provided by vendor U helps decrease the level of voiding by 1.6%. Stocking the component material above 43 days may increase the level of voiding by 1.9%. In addition, reflow soldering profile with time above liquid (TAL) less than or equal to 62 sec and with peak temperature higher than or equal to 241°C generate less voids. Finally, the via‐in‐pad design causes a concave geometry on the surface of thermal pad which contributes to the voiding formation. The amount of voiding can be further diminished by plugging the via with plated copper.

Originality/value

This research implements CHAID that extracts useful knowledge from a huge amount of manufacturing data in order to realize the complex interaction effects through automated analysis. The extent of voiding in the samples using the optimal process suggested through CHAID algorithm can be reduced from 16% to 10.2%.

Details

Soldering & Surface Mount Technology, vol. 25 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 7 September 2015

Alberto Berzoy, A. A. S. Mohamed and Osama Mohammed

The purpose of this paper is to develop a novel technique for the pre-design of a printed circuit board (PCB) of a DC-DC power converters where the placement of electric…

Abstract

Purpose

The purpose of this paper is to develop a novel technique for the pre-design of a printed circuit board (PCB) of a DC-DC power converters where the placement of electric components can cancel the electromagnetic emissions through subtractive coupling and in this sense to minimize the stray magnetic and electric fields at a specific location. For this work the location of interest is a current transducer used for control purposes positioned in the center of a DC-DC Cuk converter board as a constrain.

Design/methodology/approach

The methodology of design is based on the development of an interface software platform through MatLab script coding which interconnects the solution of a numerical analysis software and an optimization technique. The numerical analysis software is based on finite element calculations where quasi-static field analysis are performed to calculate the radiated electric and magnetic fields. The optimization technique is conducted by genetic algorithms (GAs).

Findings

The results for the proposed procedure for PCB design show a significant reduction in radiated electromagnetic (EM) field at the susceptible device in the PCB. Even when the optimization procedure is applied only for the sensor center, the field reduction is extended for a wide region around the sensor. The proposed technique not only reduces the fundamental field component but also all the harmonic contents for the electromagnetic field. It is demonstrated that it is possible to cancel the emissions by means of varying the location and orientation of the passive elements avoiding the utilization of electromagnetic interference filters and complex modulations.

Originality/value

The novelty of the design procedure falls in the fitness function programming where an interface software platform is built through MatLab scripting to connect a 3D-FE analysis and the GA. The finite element analysis address the radiated EM calculation while the GA focus in the minimization of it. This computational platform has the flexibility to be easily adapted for the PCB design of any power electronic converter where the radiated EM compliance is required as well as extended to perform emissions minimization outside or/and inside the PCB.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 27 May 2014

Weisheng Xia, Ming Xiao, Yihao Chen, Fengshun Wu, Zhe Liu and Hongzhi Fu

– The purpose of this paper is to study the thermal warpage of a plastic ball grid array (PBGA) mounted on a printed circuit board (PCB) during the reflow process.

Abstract

Purpose

The purpose of this paper is to study the thermal warpage of a plastic ball grid array (PBGA) mounted on a printed circuit board (PCB) during the reflow process.

Design/methodology/approach

A thermal-mechanical coupling method that used finite-element method software (ANSYS 13.1) was performed. Meanwhile, a shadow moiré apparatus (TherMoiré PS200) combined with a heating platform was used for the experimental measurement of the warpage of PBGA according to the JEDEC Standard.

Findings

The authors found that the temperature profiles taken from the simulated results and experimental measurement are consistent with each other, only with a little and acceptable difference in the maximum temperatures. Furthermore, the maximum warpage measurements during the reflow process are 0.157 mm and 0.149 mm for simulation and experimental measurements, respectively, with a small 5.37 per cent difference. The experimental measurement and simulated results are well correlated. Based on the validated finite element model, two factors, namely, the thickness and dimension of PCB, are explored about their effect on the thermal warpage of PBGA mounted on PCB during the reflow process.

Practical implications

The paper provides a thorough parametrical study of the thermal warpage of PBGA mounted on PCB during the reflow process.

Originality/value

The findings in this paper illustrate methods of warpage study by combination of thermal-mechanical finite element simulation and experimental measurement, which can provide good guidelines of the PCB design in the perspective of thermal warpage during the reflow process.

Details

Soldering & Surface Mount Technology, vol. 26 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 1 January 2006

Sanka Ganesan and Michael Pecht

To present and discuss open trace defects uncovered in an FR4 assembly during electrical testing.

3565

Abstract

Purpose

To present and discuss open trace defects uncovered in an FR4 assembly during electrical testing.

Design/methodology/approach

This paper presents open trace defects observed in FR4 assemblies and analyses the distribution of defects. The paper also discusses possible root causes for their occurrence.

Findings

The open trace defects that occurred during printed circuit board (PCB) fabrication should have been observed by the board manufacturer. It appears that the PCB manufacturer did not perform automatic optical inspection (AOI) and electrical testing during the manufacturing of the boards. The cost due to the rejected PCBAs was approximately 3x times that of the PCB cost.

Originality/value

The paper highlights the costly impact of uncovering a PCB defect after assembly. Based on the results of this study, the implementation of electrical testing and AOI for PCBs is recommended.

Details

Circuit World, vol. 32 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

1 – 10 of over 3000