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The purpose of this paper is to describe the effect of indium alloying on the thermal fatigue endurance of Sn3.8Ag0.7Cu solder in low‐temperature co‐fired ceramic (LTCC) modules with land grid array (LGA) joints and the feasibility of using a recalibrated Engelmaier model to predict the lifetime of LGA joints as determined with a test assembly.

Test assemblies were fabricated and exposed to a temperature cycling test over a temperature range of −40‐125°C. Organic printed wiring board (PWB) material with a low coefficient of thermal expansion was used to reduce the global thermal mismatch of the assembly. The characteristic lifetime, θ, of the test assemblies was determined using direct current resistance measurements. The metallurgy and failure mechanisms of the interconnections were verified using scanning acoustic microscopy, an optical microscope with polarized light, and scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) investigations. Lifetime predictions of the test assemblies were calculated using the recalibrated Engelmaier model.

This work showed that indium alloying increased the characteristic lifetime of LGA joints by 15 percent compared with Sn3.8Ag0.7Cu joints. SEM/EDS analysis showed that alloying changed the composition, size, and distribution of intermetallic compounds within the solder matrix. It was also observed that a solid‐state phase transformation (Cu,Ni)₆Sn₅(→ (Ni,Cu)₃Sn₄ occurred at the Ni/(Cu,Ni)₆Sn₅ interface. Moreover, the results pointed out that individual recalibration curves for ceramic package/PWB assemblies with high (≥ 10 ppm/°C) and low (≈ 3‐4 ppm/°C) global thermal mismatches and different package thicknesses should be determined before the lifetime of LGA‐type assemblies can be predicted accurately using the recalibrated Engelmaier model.

The results proved that indium alloying of LGA joints can be done using In‐containing solder on pre‐tinned pads of an LTCC module, despite the different liquidus temperatures of the In‐containing and Sn3.8Ag0.7Cu solders. The characteristic metallurgical features and enhanced thermal fatigue endurance of the In‐alloyed SnAgCu joints were also determined. Finally, this work demonstrated the problems that exist in predicting the lifetime of ceramic packages with LGA joints using analytical modeling, and proposals for developing the recalibrated Engelmaier model to achieve more accurate results with different ceramic packages/PWB assemblies are given.

The purpose of this paper is to describe the behavior of different lead-free solders (95.5Sn3.8Ag0.7Cu, i.e. SAC387 and Sn7In4.1Ag0.5Cu, i.e. SAC-In) in thermomechanically loaded non-collapsible ball grid array (BGA) joints of a low-temperature co-fired ceramic (LTCC) module. The validity of a modified Engelmaier’s model was tested to verify its capability to predict the characteristic lifetime of an LTCC module assembly implementable in field applications.

Five printed wiring board (PWB) assemblies, each carrying eight LTCC modules, were fabricated and exposed to a temperature cycling test over a −40 to 125°C temperature range to determine the characteristic lifetimes of interconnections in the LTCC module/PWB assemblies. The failure mechanisms of the test assemblies were verified using scanning acoustic microscopy, scanning electron microscopy (SEM) and field emission SEM investigation. A stress-dependent Engelmaier’s model, adjusted for plastic-core solder ball (PCSB) BGA structures, was used to predict the characteristic lifetimes of the assemblies.

Depending on the joint configuration, characteristic lifetimes of up to 1,920 cycles were achieved in the thermal cycling testing. The results showed that intergranular (creep) failures occurred primarily only in the joints containing Sn7In4.1Ag0.5Cu solder. Other primary failure mechanisms (mixed transgranular/intergranular, separation of the intermetallic compound/solder interface and cracking in the interface between the ceramic and metallization) were observed in the other joint configurations. The modified Engelmaier’s model was found to predict the lifetime of interconnections with good accuracy. The results confirmed the superiority of SAC-In solder over SAC in terms of reliability, and also proved that an air cavity structure of the module, which enhances its radio frequency (RF) performance, did not degrade the reliability of the second-level interconnections of the test assemblies.

This paper shows the superiority of SAC-In solder over SAC387 solder in terms of reliability and verifies the applicability of the modified Engelmaier’s model as an accurate lifetime prediction method for PCSB BGA structures for the presented LTCC packages for RF/microwave telecommunication applications.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Surface mount technology (SMT) is widely used and plays an important role in electronic equipment. The purpose of this paper is to reveal the effects of interface cracks on the fatigue life of SMT solder joint under service load and to provide some valuable reference information for improving service reliability of SMT packages.

A 3D geometric model of SMT package is established. The mechanical properties of SMT solder joint under thermal cycling load and random vibration load were solved by 3D finite element analysis. The fatigue life of SMT solder joint under different loads can be calculated by using the modified Coffin–Manson model and high-cycle fatigue model.

The results revealed that cracks at different locations and propagation directions have different effect on the fatigue life of the SMT solder joint. From the location of the cracks, Crack 1 has the most significant impact on the thermal fatigue life of the solder joint. Under the same thermal cycling conditions, its life has decreased by 46.98%, followed by Crack 2, Crack 4 and Crack 3. On the other hand, under the same random vibration load, Crack 4 has the most significant impact on the solder joint fatigue life, reducing its life by 81.39%, followed by Crack 1, Crack 3 and Crack 2. From the crack propagation direction, with the increase of crack depth, the thermal fatigue life of the SMT solder joint decreases sharply at first and then continues to decline almost linearly. The random vibration fatigue life of the solder joint decreases continuously with the increase of crack depth. From the crack depth of 0.01 mm to 0.05 mm, the random vibration fatigue life decreases by 86.75%. When the crack width increases, the thermal and random vibration fatigue life of the solder joint decreases almost linearly.

This paper investigates the effects of interface cracks on the fatigue life and provides useful information on the reliability of SMT packages.

The purpose of this paper is to describe key failure mechanisms observed during the development of the advanced packaging technology. Extensive accelerated stress tests are conducted to collect failure data and understand failure characteristics and failure trends. The results will be useful for design improvement and failure rate predictions.

High density chip scale packages (CSP) are developed to meet the needs for high performance and small form‐factor products, but with reduced process procedures and product cost. Test‐to‐failure approaches are applied to evaluate the failure rate and reliability models instead of compliance qualification testing approaches.

The study shows Cu‐trace cracking failure can be treated as random failures and analyzed using a constant failure rate approach. The acceleration factor for the Cu‐trace cracking failure mechanism exhibits a large power exponent comparing to the parameters used in reference models. In addition, the solder joint failure data collected through the study do not fit well with the well‐known solder fatigue life model. Moreover, the test results affirm the test‐to‐failure approach adopted in data collection is providing more accurate failure characteristics compared to the compliance qualification testing approach.

The paper shows that the reliability performance of package technology can be improved by enhancing the package design, improving manufacturing processes and materials optimization.

This is an original research paper and the test‐to‐failure approach in the reliability study helps provide realistic reliability predictions.

This paper aims to present a machine learning framework for using big data analytics to predict the reliability of solder joints. The purpose of this study is to accurately predict the reliability of solder joints by using big data analytics.

A machine learning framework for using big data analytics is proposed to predict the reliability of solder joints accurately.

A machine learning framework for predicting the life of solder joints accurately has been developed in this study. To validate its accuracy and efficiency, it is applied to predict the long-term reliability of lead-free Sn96.5Ag3.0Cu0.5 (SAC305) for three commonly used surface finishes such OSP, ENIG and IAg. The obtained results show that the predicted failure based on the machine learning method is much more accurate than the Weibull method. In addition, solder ball/bump joint failure modes are identified based on various solder joint failures reported in the literature.

The ability to predict thermal fatigue life accurately is extremely valuable to the industry because it saves time and cost for product development and optimization.

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

The transition from comprehensive school to either an academic or a vocational track and from academic track to tertiary education are the key educational transitions during adolescence and young adulthood in many European educational systems. The present chapter approaches engagement and disengagement during these key educational transitions in the context of the 4-C (channelling, choice, co-regulation, compensation) life-span model of motivation and phase-adequate engagement model. In accordance with the life-span model of motivation and the phase-adequate engagement model, school transitions are triggers that channel the engagement and disengagement processes. The former process reflects school-related engagement, whereas disengagement is a key element of the school-burnout process. Engagement in the school context is defined as a positive, fulfilling work-related state of mind characterized by vigor and energy, dedication, and absorption. School burnout comprises three dimensions in terms of exhaustion due to school demands: a cynical and detached attitude toward the school, feelings of inadequacy as a student, and disengagement. Cynicism is manifest in an indifferent or distal attitude toward school work in general, a loss of interest in it, and not seeing it as meaningful. Inadequacy refers to a diminished sense of competence, achievement, and accomplishment as a student.

The purpose of this paper is to verify how solder joint properties correlate with soldering profile set-up. These characteristics act against each other. All observed properties may significantly affect the quality and reliability of solder joints. The purpose is also to design recommendations for manufacturers of electronic assemblies.

The samples for experiment were reflowed by using a laboratory reflow oven. A LEXT laser confocal microscope was used for wetting angle and intermetallic compound (IMC) thickness measurement. The ionic contamination was measured by using a contaminometer.

The appropriate choice of soldering profile is very important for the reliability of electronic assemblies. The higher temperatures or longer preheating and soldering times improve the wetting angle. Likewise, there is also the activation of all the fluxes. The result is low contamination with printed circuit boards (PCBs). On the other hand, we must not forget that higher temperatures and longer soldering time also affect the thickness of the IMC. The outer limits recommended by the manufacturer were selected for the soldering profile set-up. Even within these limits, it is possible to achieve an improvement in the wetting angle, an improvement in levels of PCB contamination and an increase in the thickness of the IMC. This paper presents the results achieved for solders Sn42Bi57.6Ag0.4, Sn96.5Ag3Cu0.5 and Sn97Ag3.

The gained knowledge on the correlation between IMC thickness, solderability of PCB and PCB contamination caused by different soldering profile set-ups can help to prevent reliability problems because each of the named effects has a significant influence on reliability.