Search results

High performance aluminium nitride water cooled heat sinks were fabricated and characterized. A variety of fabrication processes were employed to meet different cooling requirements. They include laser cut microchannel coolers for chip and multichip heat sinks as well as dry pressed pin fin heat sinks for power electronics. Thermal simulation was used to optimize the heat sink design.

Multichip module packaging enables a significant increase of interconnect densities and performance of electronic systems. Multichip module technology based on laminate materials (MCM‐L) is attractive due to low cost and use of the standard equipment used by PCB manufacturers. The most limiting factor for higher wiring densities in PCB technology is the mechanical drilling of plated‐through holes. Using 0.3 mm drill diameters, 0.5 mm land diameters are required, which limit the area for routing of tracks. Therefore, alternative dielectric materials, which can be structured photolithograpically, by plasma etching or laser drilling, are very attractive for MCM‐L technology. In this paper an epoxy resin layer, commercially available as a solder mask, is investigated as an interdielectric layer. Via hole drilling is investigated using an excimer laser. To show process feasibility, a two‐layer wiring system is fabricated using the excimer laser structured epoxy resin as an interdielectric layer on conventional epoxy board (FR‐4).

The members of the chapter at the annual meeting held on 27 November 1992 in Brno decided not to split after the separation of Czechoslovakia. It was suggested to organise a larger chapter from the Central European States to provide greater co‐operation and better functioning of the smaller chapters. A new name for the chapter was proposed — Central European Chapter (CEC) — to express neutrality and to point out that the chapter is open to other neighbouring chapters and to new members from the states where no national chapter yet exists.

This study aims to provide a flexible and cost-effective solution of 3D heterogeneous integration for applications such as micro-electro-mechanical system (MEMS) applications and smart sensor systems.

A novel 3D system-in-package (SiP) based on stacked silicon submount technology was successfully developed and well-demonstrated by the fabrication and assembly process of a selected smart lighting module.

The stacked module consists of multiple layers of silicon submounts which can be designed and fabricated in parallel. The bonding and interconnecting process is quite simple and does not require complicated equipment. The 3D stacking design offers higher silicon efficiency and miniaturized package form factor. The submount wafer can be assembled and tested at the wafer level, thus reducing the cost and improving the yield.

The embedding design presented in this paper is applicable for modules with limited number of passives. When it comes to cases with more passive devices, new process needs to be developed to achieve fast, inexpensive and reliable assembly.

The presented 3D SiP design is novel for applications such as smart lighting, Internet of Things, MEMS systems, etc.

In this paper, a computational analysis is presented for the comparison of wafer level chip scale package‐on‐build‐up PCB assemblies with various solders and microvia configurations. The printed circuit board of the assembly has one build‐up layer on one side. For comparison, the board with two build‐up layers on the same side is studied as well. Furthermore, two solder joint materials, namely, 62Sn–2Ag–36Pb and 96.5Sn–3.5Ag are studied for comparison. The assembly is simulated by a finite element model and the model is analyzed under thermal cyclic loading. A comprehensive stress analysis is performed and comparisons are made for assembly deformation, stress/strain ranges, and creep responses.

Diameter and depth of craters and removing efficiency of the material of RCC^R (resin coated copper) used in PCB by a single pulse energy of 355nm YAG laser with a variety of pulse energy, pulse width and defocus have been studied in the paper. It is shown that the ablation rates per pulse are much higher when compared with those at 248nm. The crater diameter increases monotonically with the pulse energy. However, when the pulse energy is very high and the power density is higher than 4.0 × 10⁹W/cm², the crater depth and removing efficiency decrease with the increase of pulse energy. The pulse width has an important influence on the crater diameter and volume when the pulse width changes from 24ns to 38ns, whereas the influence on the crater depth is little. The influences of defocus on ablation results depend on the power density of laser beam. A certain defocus can make both crater diameter and removing efficiency increase for a relatively high power density. Meanwhile, the thermal effect in the process of 355nm laser ablation of RCC^R cannot be neglected.

The solder‐joint reliability of solder‐bumped wafer level chip scale package (WLCSP) on microvia build‐up printed circuit board (PCB) subjected to thermal cycling conditions is investigated in this study. The 62Sn36Pb2Ag solder joints are assumed to be: an elastic material; an elastic‐plastic material; and a creep material which obey the Garofalo‐Arrhenius steady‐state creep constitutive law. The stress and strain in the corner solder joint of the WLCSP assembly are presented and compared for these three material models. Also, the results presented herein will be compared with that from creep analysis of the WLCSP on PCB without microvia build‐up layer.

This paper aims to look at how participant photography can be used in human resource development (HRD) as a research method that is innovative and inclusive. In published work on traditional photo elicitation methods, the participant is shown previously prepared visual images to create knowledge. This can provoke an inaccurate depiction due to the images being previously prepared. Participant photography differs greatly from the traditional photo-elicitation method. In participant photography, the participant is provided with the opportunity to capture their own visual images of the surrounding environment, allowing for data to be captured through their own eyes. More notably, participants voice their own experiences after taking the photographs as a means for providing rich data for researchers.

Participant photography is an innovative qualitative research method where the research participant is encouraged to document their lived experiences through images taken by the participant. Additionally, the participants take part in individual interviews and group individual sessions to further explain the images.

The research findings can lead to deeper insight into the research topic and even accommodate potential issues related to literacy and language barriers. By introducing a new qualitative research method to HRD, the lived experiences can be documented and examined in a new, different and arguably more accurate way.

Literature discussing participant photography in HRD is limited. Although this limitation puts constraints on this study, it creates an opportunity to further define how participant photography can be used in HRD. This method offers a means for HRD researchers and practitioners to focus on the voices of participants to improve organizations.

This study addresses how participant photography can be used in the field of HRD by describing the process of participant recruitment, implementation of the method, participant interviews, group discussion and analysis. Specifically, this study focused on the practical application, including the method’s strengths, potential weaknesses and ethical challenges.

The method of participant photography has been commonly used in community-based studies, public health projects and medical research projects, yet in ever-changing HRD needs, there are many advantages for the field of HRD to implement this method.

Although the concept of participant photography is still in its infancy in HRD, this study explains how participant photography can be used for both researchers and practitioners to gain a deeper understanding and knowledge of topics related to HRD.

The purpose of this paper is to demonstrate a novel 3D system-in-package (SiP) approach. This new packaging approach is based on stacked silicon submount technology. As demonstrators, a smart lighting module and a sensor systems were successfully developed by using the fabrication and assembly process described in this paper.

The stacked module consists of multiple layers of silicon submounts which can be designed and fabricated in parallel. The 3D stacking design offers higher silicon efficiency and miniaturized package form factor. This platform consists of silicon submount design and fabrication, module packaging, system assembling and testing and analyzing.

In this paper, a smart light emitting diode system and sensor system will be described based on stacked silicon submount and 3D SiP technology. The integrated smart lighting module meets the optical requirements of general lighting applications. The developed SiP design is also implemented into the miniaturization of particular matter sensors and gas sensor detection system.

SiP has great potential of integrating multiple components into a single compact package, which has potential implementation in intelligent applications.

This paper investigates consumer engagement, evaluation and beliefs of domestic products and the influence of such associated attributes communicated via domestic COO labelling within the United Kingdom.

A visual ethnographic approach utilising the methods of autophotography and photo elicitation interviews was conducted to explore consumers' interaction with the domestic COO label and provenance advertising.

The results of photo elicitation interviews revealed both positive and negative cognitive, affective and normative implications of domestic provenance labelling of influence emerging within consumers.

The findings are applied to the context of the United Kingdom, with contextual limitations acknowledged of doing so. Convenience sampling limitations are also acknowledged.

The findings provide UK-based FMCG manufacturers and retailers insight into the associated attributes of domestic brand and products interpreted by consumers, communicated via a COO label, to assist in their purchasing strategies.

This paper seeks to contribute towards the understanding of provenance labelling influence on consumers for products within the FMCGs sector, whilst specifically commenting upon attributes of reliance and influence that may assist navigation of changing priorities and national sentiments.