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Investigations were aimed at evaluation of assembly properties of conductive layers cofired with LTCC substrates. The usefulness of these layers for low‐temperature soldering, joining with adhesives or for wire bonding was tested. The samples were manufactured from inks and glass‐ceramic sheets from three known LTCC producers. Different material combinations and various temperature‐time profiles of firing were used. The investigations were on: wettability measurements of conductive layers, evaluation of the layer resistance to dissolution, the deep analyses of particular wire bonding processes and the joint quality assessment at the time of welding, and the joint strength measurements. In the case of adhesive connections the resistance measurements of joints were applied. Scanning electron microscopy analyses were applied and metallographic examinations of sample cross‐sections were undertaken. The results of the investigations allowed us to choose films with appropriate bonding properties, and to explain the mechanism of joint failure.

The paper aims to present the original and easy for application methods of mechanical strength and electrical properties examination of conductive adhesives and adhesive joints at room as well as at liquid nitrogen temperatures.

The Epoxy Technology EPO‐TEK E4110 and EPO‐TEK H20E adhesives were investigated both in the form of the loose rod and as the printed layers on alumina substrates. Additionally, the mechanical and electrical properties of adhesive joints in low temperatures were investigated, where their characteristics depended on the physical properties of joined elements.

The results indicate the substantial influence of the substrate material on the adhesive resistivity. The joints samples were exposed to multiple thermal shocks in the range from room down to liquid nitrogen temperatures and it was observed that the joints strength and resistance stability could be reached in determined curing conditions of the adhesive.

It is generally stated that tested adhesives can be fully suitable for work in low temperatures. However, it should be underlined that these adhesives' properties change after cooling them down to the liquid nitrogen temperature – the strength growths and the resistance diminishes (about few times).

The paper examines mechanical strength and electrical properties of conductive adhesives and adhesive joints at various temperatures.

Investigations were aimed at the evaluation of degradation mechanisms in ultrasonically welded joints of AlSi1 per cent wire (25 μm in diameter) and Au substrate (100 μm thick), relatively thick elements, exposed to high temperature of 300°C up to 100 h. Thermally activated Al diffusion into Au generates the formation of intermetallic compounds in the area of the bond interface. With the longer thermal exposure the expansion and transformation of intermetallic compounds is observed. The characteristic “intermetallic compounds core” is formed, which from one side penetrates into the wire material and from another spreads deeply into the Au substrate up to enhancing band of Kirkendall voids.

ISHM, acting as a professional body for a very large sector of microelectronics manufacturing and design, naturally takes a strong and active interest in the education and training of people working in its industry. An annual Education Prize is awarded by the Society at either undergraduate or post‐graduate level and sometimes both. The aim of the awards is to encourage the writing up of work completed by students as part of the education route. It may be from an internal project such as a B.Eng. report or a Masters Dissertation. It may also be work done by the student in an industrial placement. These three authors or their institutions have been associated with entries which have been awarded a prize. The winning paper is normally published in Hybrid Circuits.

This conceptual paper aims to stimulate discussion on the growing influence of digital technologies on the success of learners in tertiary institutions.

The paper is grounded in a synthesis of the professional literature showing how learners entering tertiary institutions have been influenced by their pervasive use of digital technologies. This evidence suggests that a more integrated use of libraries is needed, and more collaboration among librarians, educators and learners will be fundamental to responding to the changing learning landscape.

The findings indicate that today's “new learners” expect more control of their learning situations, prefer active learning and they engage in networked communities for their social and professional lives. Research also shows that, while these learners are committed users of a wide range of digital technologies, they require support in developing their information and critical literacies. The paper also identified the tendency for educators to limit their uses of digital technologies for course management and the addition of online resources to their teaching, while resisting any fundamental change in the structure and delivery of courses. Academic libraries are responding to these challenges by creating more social learning spaces, integrating services for instructors and students and becoming more active partners in the educational community.

The limitations identified here include the widening gap between those living and learning with digital technologies and the majority of the world youth still struggling to gain full access.

The research is one of the few position papers to begin its argument with a description of today's digital learners and then to connect their learning needs with the many changes in libraries at the tertiary level. The paper attempts to conceptualize how libraries can take a leadership role in bridging the gap between the learning styles and needs of today's students and the challenges of building new learning landscapes in tertiary institutions.

Colorfastness properties of dyed degummed and dyed stannic chloride weighted silk fiber were studied as a function of exposure to sunlight in air, washing with soap solution and spotting with alkalis.

Improved multi-voltine variety of degummed silk fibers was weighted with the treatment of stannic chloride at the varying pH level. Maximum weighting of silk fiber was achieved at the optimum SnCl₄ concentration, pH of the solution, time and temperature. The degummed (un-weighted) and weighted silk fibers were then dyed with Direct Blue 1 and Direct Red 28 dyes at the optimized dying conditions.

The role of base (Na₂CO₃) on dyeing of weighted silk fiber with Direct Red 28 was found very influential. The loss in tenacity of degummed silk fiber was higher than that of SnCl₄ weighted silk fiber when they were exposed to sunlight in air.

The colorfastness of weighted dyed silk was comparatively higher than that of un-weighted dyed silk.

The purpose of this paper is to investigate the effect of electroless NiAu (ENIG) deposition on the failure mechanisms and characteristic lifetimes of three different non‐collapsible lead‐free 2nd level interconnections in low‐temperature co‐fired ceramic (LTCC)/printed wiring board (PWB) assemblies.

Five LTCC module/PWB assemblies were fabricated and exposed to a temperature cycling test over a −40 to 125°C temperature range. The characteristic lifetimes of these assemblies were determined using direct current resistance measurements. The failure mechanisms of the test assemblies were verified using X‐ray and scanning acoustic microscopy, optical microscopy with polarized light, scanning electron microscope (SEM)/energy dispersive spectroscopy and field emission‐SEM investigation.

A stable intermetallic compound (IMC) layer is formed between the Ni deposit and solder matrix during reflow soldering. The layer thickness does not grow excessively and the interface between the layer and solder is practically free from Kirkendall voids after the thermal cycling test (TCT) over a temperature range of −40 to 125°C. The adhesion between the IMC layer and solder matrix is sufficient to prevent separation of this interface, resulting in intergranular (creep) or mixed transgranular/intergranular (fatigue/creep) failure within the solder matrix. However, the thermal fatigue endurance of the lead‐free solder has a major effect on the characteristic lifetime, not the deposit material of the solder land. Depending on the thickness of the LTCC substrate and the composition of the lead‐free solder alloy, characteristic lifetimes of over 2,000 cycles are achieved in the TCT.

The paper investigates in detail the advantages and disadvantages of ENIG deposition in LTCC/PWB assemblies with a large global thermal mismatch (ΔCTE≥10 ppm/°C), considering the design and manufacturing stages of the solder joint configuration and its performance under harsh accelerated test conditions.

The purpose of this paper is to investigate the feasibility of using land grid array (LGA) solder joints as a second-level interconnection option in low-temperature co-fired ceramic (LTCC)/printed wiring board (PWB) assemblies for telecommunication applications. The characteristic behaviour of two commercial lead-free solder materials (Sn4Ag0.5Cu and Sn3Ag0.5Cu0.5In0.05Ni) in reflow processes and thermal cycling tests are also evaluated.

The effect of the reflow temperature profile on voiding in two lead-free solders in LTCC/PWB assemblies was investigated using X-ray and scanning electron microscopy (SEM) investigations. The test assemblies were fabricated and exposed to a temperature cycling test (TCT) in a 0-100°C or −40 to 125°C temperature range. Organic PWB material with a low coefficient of thermal expansion (CTE) was primarily used. In addition, to compare LGA assemblies with low and high global thermal mismatches, an LTCC module/FR-4 assembly was also fabricated and exposed to a TCT in a 0-100°C temperature range. The characteristic lifetime of the test assemblies was determined using DC resistance measurements. The failure mechanisms of the interconnections were verified using scanning acoustic microscopy, SEM and finite element (FE)-SEM investigations.

This work showed that the solderability of AgPt-metallized LTCC modules was poor, resulting in excessive voiding. This problem was avoided by using pre-tinned modules. In the test assemblies, the Sn4Ag0.5Cu joints had a lower void content and a higher characteristic lifetime compared with the Sn3Ag0.5Cu0.5In0.05Ni joints. Furthermore, it was observed that the Sn3Ag0.5Cu0.5In0.05Ni joints were more prone to fail along the interface between the Ag₃Sn layer and the solder matrix than were the Sn4Ag0.5Cu joints. It was assumed that the observed difference in the primary failure mechanisms resulted in the decreased lifetime duration of the SnAgCu-InNi/Arlon in both temperature cycling conditions.

The results proved that the solderability of both solders in AgPt-metallized modules in a typical surface mount technology process was poor; however, the solderability of the test modules can be notably enhanced with pre-tinned pads. This work also demonstrated the effect of the metallization/solder pair on the failure mechanisms and failure rate in LTCC/PWB assemblies with LGA joints; the work also proved in the TCT, over a temperature range of 0-100°C, that using the present LGA joints in LTCC/PWB assemblies with a high global thermal mismatch did not increase the lifetime duration of the joints to the preferred level (3,000 cycles), whereas the performance of these joints was adequate in assemblies with a low global thermal mismatch. Moreover, the results indicated that using the LGA joint configuration enhanced the reliability of the LTCC/PWB assemblies compared with similar assemblies with collapsible ball grid array solder spheres.