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The purpose of this paper is to compare the single-sided packaging structure and double-sided packaging structure of high-power module and study the overall heat dissipation performance and reliability of the module.

In this paper, the single-sided packaging structure and double-sided packaging structure of power module are designed based on Wolfspeed products. This paper is analyzed by finite element method. First, the heat dissipation performance of single-sided packaging structure and double-sided packaging structure is analyzed; second, the deformation and stress of single-sided packaging structure and double-sided packaging structure are compared and analyzed; and finally, the cumulative plastic deformation of single-sided packaging and double-sided packaging structures are compared and analyzed, and the fatigue life of the structure is calculated based on the plastic deformation.

In the heat transfer simulation, under the same power input, the heat dissipation performance of single-sided packaging structure is not as good as that of double-sided packaging structure. Under the reliability simulation of the same temperature cycle standard, the maximum equivalent stress of single-sided packaging structure is lower than that of double-sided packaging structure, but the fatigue life prediction based on plastic strain shows that the fatigue life of double-sided packaging structure is not different from that of single-sided packaging structure.

This paper creatively simulates the thermal characteristics and reliability of single-sided packaging structure and double-sided packaging structure and proves the advantages of double-sided packaging structure compared with single-sided packaging structure from the aspects of heat transfer performance and reliability.

A large-scale detection system with more data in short time bins, small dead space and small signal identification is the ideology the scientists pursuing. These proposed demands are able to be solved by 2.5 D integration. The substance of a 2.5 D integration is called silicon interposer, which consists of the through silicon via (TSV) and redistribution layer. However, the state-of-the-art silicon interposer is not able to sustain its own mechanical strength with the detector/readout array often sitting as standalone in large science facilities and fails to reduce the expansions on the installation of the components due to its insufficient thickness and size. This study aims to propose a moderation of current interposer with large-sized, standalone properties.

This paper proposes an interposer based on double-sided silicon vias (DSSVs) interconnection. Unlike conventional interposer that is interconnected by TSVs, DSSVs interposer is interconnected by top vias (T-vias) and bottom vias (B-vias).

The fabrication process of DSSVs interposer is introduced, and the superiority of the double-sided interconnection process with two etch-stop layers is described in detail. The impact of different T-vias depth on DSSVs interconnections in the same wafer is discussed and two times PI opening processes are proposed to eliminate air bubbles in the B-via. The relationship between the interposer thickness and warpage is studied by finite element analysis simulation and experiment. The prototype of the DSSVs interposer with a size of 100  × 100 mm and a thickness of 318.2 µm is fabricated, and electrical tests including short tests and continuity tests are carried out.

This paper proposes a large-sized and stand-alone interposer based on DSSVs interconnection.

Electronic packaging technologies, such as pin grid arrays, increasingly small pitch surface mount, and double‐sided assemblies are all aimed towards the highest possible product density, with improved performance. The gap between inspection effectiveness and advances made in packaging technologies is becoming larger. As efforts proceed, to learn more about critical factors influencing reliability of solder joints, it is prudent to ensure that printed wiring assembly (PWA) design rules evolve to permit the broadest range of anticipated automated inspection requirements. The range of automated inspection technologies can all be made more effective through careful design of electronics for inspection. Significant opportunities lie in both PWA layout and design, as well as electronic component design, tolerancing, and standardisation. Many inspection issues are shared, but with increased recognition of digital radiography's unique capabilities; this discussion will emphasise X‐ray inspection issues.

The Center for Industrial Research (SI), the University of Oslo (UiO) and a group of Norwegian companies have collaborated between 1990 and 1992 in the research programme ‘Industrial Microelectronics’ with a total cost of 30 MNOK. The programme was sponsored by the Norwegian Scientific and Industrial Research Council (NTNF) as one of the twin programmes constituting a national research initiative in microelectronics. The motivation for the programme is the recognition of microelectronics as a key technology commanding the performance and market success of many of the electronics systems from the Norwegian electronics industry towards the year 2000. The main objective is to stimulate industrial innovation by developing, transferring and exploiting knowledge and methods based upon advanced microelectronics. Focused activities are silicon sensor technology, combined analogue/digital design of application‐specific integrated circuits, large scale instrumentation, sensor packaging and thermal management of electronic systems. SI is focusing on applied research, UiO on education, and collaborating Norwegian companies are using the results in their own R&D projects. It is anticipated that the research results will be fully industrialised within 3–5 years. The programme is co‐ordinated with other Norwegian government‐sponsored research activities as well as European research programmes based on microelectronics. The programme is organised in projects and monitored with a set of milestones strongly indicating the achievement of successful industrial innovation, research results of international standing and high‐quality education of key personnel for the industry. Several successful examples of the research results are highlighted: Design and process methodology for double‐sided microstrip silicon radiation sensors for detection of high energy elementary particles, silicon‐to‐silicon and silicon‐to‐thin film anodic bonding processes for sensor fabrication, combined analogue/digital application‐specific integrated circuits for front‐end instrumentation applications, packaging of radiation sensors and thermal management of electronic systems by evaporation cooling. It is concluded that the programme has successfully achieved results in harmony with the objective.

The purpose of this paper is to present a double‐sided tubular linear machine layout direct‐drive applications, with particular focus on wave‐energy conversion. The paper documents both the computational and mathematical analysis of this novel machine layout.

The selection and finite‐element optimisation of the permanent‐magnet array is presented. The machine is then modelled using magnetic circuit theory. By simultaneously solving the system of equations, a demonstrative design is developed and simulated so as to validate the mathematical model and compare the performance of the new layout with a traditional layout.

A surface‐mounted magnetic array, with unshaped‐poles, is most suitable for the proposed layout. The mathematical model exhibits a suitable level of accuracy for design and analysis purposes. The calculated resultant force differs from the FEA calculation by 1.85 per cent. A higher force‐density is exhibited by the proposed layout, when compared with flat layouts, with a reduction of 36.5 per cent in the spatial footprint and magnetic material of the machine.

Although the research is focused on the application of wave‐energy conversion, the techniques are application‐independent. However, certain design decisions should be reviewed for other applications.

The practical implementation of such a machine poses many mechanical obstacles. These have been solved in theory, and are being implemented at the time of writing.

The combination of a double‐sided and a tubular layout has not previously been researched. This research fills that void and provides designers with the technical background and a mathematical model for development of such devices.

The purpose of this paper is to analyze and figure out the temperature field and thermal stress field with the calculation model of thermal insulation material and composite material.

The paper adopted the three-dimensional finite element algorithm.

The simulated results showed great shearing strength between the chipset and the printed circuit board. The position of chip exerts great influence on the distribution of temperature field and thermal stress field of circuit board. The reasonable distribution of chip will effectively reduce the temperature extremum and stress extremum of circuit board.

The paper analyzes and presents a discussion of the problems relating to the density of electronic packaging. The analysis process and the method of the paper provide essential help in resolving electronic device heat problems.

While promising significant improvements in the cost and performance of electronic systems, the advent of new area array packaging concepts such as the BGA and newer area array CSPs has placed significant new demands on the substrates used in their interconnection. New methods such as build‐up multilayers and micro vias and co‐lamination of inner layers have been described and implemented by a number of different firms in an attempt to address this important issue. One such method employs simple double‐sided plated through hole flex circuits and the use of conductive pastes and bondplies to provide reliable electrical and mechanical connection between layers during a simple lamination cycle. The process, briefly described herein as a co‐laminated multilayer flex, is detailed in terms of both process steps and manufacturing flow. The structure of the interconnection substrate is also modeled and examined to determine its electrical performance potential according to electrical modeling software. Finally, detailed are the performance of the structure in reliability testing and an analysis of the expected design and performance advantages that might be obtained by such type constructions in combination with BGAs and area array CSPs.

This study aims to investigate the use of convertible securities and control rights covenants for a sample of 53 Portuguese, Spanish and German venture capital (VC) firms.

A relatively new methodology in business sciences – a fuzzy set qualitative comparative analysis – that considers both quantitative and qualitative factors is used for obtaining a solution that best fits the empirical data.

The results show that the use of convertible securities is affected by agency predictions, namely, the anticipated severity of double-sided moral hazard problems. On the other hand, a mixed support is provided to the agency predictions regarding the use of control right covenants. The results seem to suggest that control right covenants tend to play a different role from convertible securities in the optimization of contract design for VC-backed investments.

Existing literature on VC contract design is extended by providing a cross-border analysis to VC financing decision.

The purpose of this paper is to present the stages for manufacturing a low‐cost miniaturized prototype device, which observes the restrictions of implantable medical devices. The device measures the electrocardiography. The power for the implant is received passively as the same magnetic field as data is transferred to the reader device.

In this manufacturing technique, only easily attachable commercial available components are used, etching is used to simply produce a low‐cost double‐sided flexible printed circuit board which is converted to 3D by folding.

The circuit board was folded into the final shape after component attachment and the final result was a compact 3D package within the specifications determined by the electronics designer. The miniaturized prototype device was successfully tested both in vitro and in vivo.

The manufacturing technique of the sensing device can be readily adapted to other devices that need to be miniaturized. The coatings used for electrical insulation and chemical protection and the type of adhesives used for folded packages are easily utilized in similar miniaturization prototypes. By using bare chips, the final product would have been even smaller but for prototyping it is cheaper and faster to use easily acquired and attached components. In the case of mass production, the whole new design, where bare chips with flip chip attachments, integrated passives and/or stacked 3D packages with design considerations such as electrical, thermal and mechanical engineering is justified.

Earl Moon of Viking Interconnect Systems addressed those present at the 21 May meeting on the subject of ‘Characterisation of Military SMT/MLB Requirements as a Function of the Total Package Concept’.