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The purpose of this study was to investigate amount of food waste and the number of food packages used in Finnish households with university students. The aim of the paper is to answer the following research questions: How much avoidable food waste is generated in the participating various sized households? How much unavoidable food waste is generated in the participating various sized households? How many food packages are classified as deposit, municipal waste or recycled in the participating various sized households?

The data was collected among the students in Seinäjoki University of Applied Sciences. A total of results from 432 households with 890 persons are presented. The participating households weighed their unavoidable and avoidable food waste and calculated the food packages during one week. The results were analysed in Excel and the statistical significance assessed using a t-test.

The average avoidable and unavoidable food wastages were 498 g/week/person, i.e. 25.9 kg/year/person and 543 g/week/person, i.e. 28.3 kg/year/person, respectively. Single-person households generate more avoidable and unavoidable food waste as well as packages per person than other sized households. The results show that there is no correlation between the amount of avoidable food waste/person, unavoidable food waste/person or packages/person.

This kind of research has sparsely been reported. The food and package wastage definitions vary, and thus it is difficult to compare these results with other reported results.

The purpose of this study is to offer the advanced leadless leadframe package which achieve small form factor and high thermal and electrical performance, according to the continuous market requirement. Because of demand and trends, new package structures that can accommodate many pins (I/Os) while maintaining the excellent thermal and electrical properties of the leadframe package was studied. Different from conventional leadframe and laminate packages, it must have the large-exposed pad for thermal dissipation and design flexibility to deploy signal, ground and power selectively.

In this study, the routable molded leadframe (rtMLF®) package applying the pre-resin MLF substrate was introduced. The structural advantages, in terms of design flexibility, were checked by adopting the specific electrical feature. Also, the excellence of thermal and electrical performance was confirmed by simulation. The sample was manufactured, and its package robustness was validated by reliability test.

rtMLF package that enables one layer substrate but routable pattern on top layer differently from existing leadframe package was developed and studied if it overcome the limitations of leadframe and laminate products. Asymmetric land layout was designed and special features to keep electrical interference was applied to prove design flexibility. The thermal and electrical simulation has been executed to check the advantages. And key differentiations were identified. Finally, actual sample was manufactured, and structural robustness was validated by package level and board level reliability.

The differentiation of new semiconductor package was introduced and its excellence was verified by electrical and thermal simulation as well as reliability test. It is expected to be adopted for alternative solutions not covered by the existing products.

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.

Packages for multichip modules in military airborne applications must hava some fundamental characteristics: high thermal conductivity, low density, good mechanical properties and a coefficient of thermal expansion nearly equal to that of the microelectronic substrate installed in the package. In many cases, the substrate is alumina with a CTE of 6.5 ppm/°C. Materials such as aluminium, titanium or Kovar fulfil only part of the above requirements. This is critical when large packages are used, such as in electronic warfare systems where modules include wideband RF circuits with large alumina substrates next to dense digital circuits. The solution is then aluminium/ silicon carbide (Al/SiC). The aim of the paper is to present the development and qualification of large packages combining both RF and digital circuitry. The size taken into account in the study is 220 × 220 mm: it covers most of the electronic needs in terms of surface. Various aspects have been analysed from the perspective of the package manufacturer and the end‐user. The interest of Al/SiC is shown by a thermal analysis of a conduction cooled module with different core materials: the reduction in temperature gradient, which for some components reaches 20° C, has a strong effect on the module reliability. The different technological choices, for a first type of packages, are described: an Al/SiC baseplate with an iron‐nickel alloy for the ring and the lid, brazed feedthroughs (within the Al/SiC baseplate) and connectors, surface treatment, ring brazing material, lid welding technique. A second type of packages is also presented: the main difference lies in the interconnections. RF ceramic (HTCC) inserts are introduced in the ring frame. Various RF measurements show the interest of the different package technologies, especially the ceramic inserts with very good results up to 20 GHz.

The purpose of this paper is to describe a pilot study characterizing the domestic usage of food packaging (amount and type) at the household level.

Collection and detailed characterization is carried out, from a sample of Portuguese consumers, of packages used at home during a seven‐day period.

The daily intake of domestically consumed, packaged food ranged from 5 to 50 g/kgbw. The average intake value for children below 12 years old was 26 g/kgbw. Considering all packaging materials, package usage ranged from 0.1dm2/day.kgbw to 0.6dm2/day.kgbw. Packaging usage factors and food‐type distribution factors for each packaging material were estimated.

The period of packaging collection and the size of the sample limit the degree of generalized conclusions that can be drawn.

The data collected are the base for the development of a framework and could make an important contribution to the assessment of consumer exposure to substances migrating from packages into food, in this case of the Portuguese consumer.

The results achieved are analysed in relation to the current assumptions made for the safety assessment of materials in the relevant European legislation. Furthermore, the results achieved can be used in a probabilistic approach to these assessments as the distributions of values, and not only the per capita values, are known.

Plastic ball grid array (PBGA) packages are non‐hermetic surface mount packages, designed in response to market demands for cost‐effective, high I/O count, small footprint, and low profile components. Because of the materials and construction, PBGA packages can be vulnerable to failure mechanisms associated with exposure to temperature and humidity. In some applications, conformal coating has been used as a potential means to mitigate these problems by enhancing moisture ingress resistance. This study focused on the ability of two popular kinds of conformal coatings to protect PBGA packages from moisture‐induced failures. As part of the study, PBGA packages with and without conformal coatings were subjected to moisture ingress, moisture desorption and unbiased high temperature high humidity tests. The principal failure mechanisms observed were delamination and cracking in the packages. Although it was observed that parylene coating did slow down the moisture ingress, the high temperature high humidity tests did not demonstrate that two tested conformal coatings had significant protection against moisture‐induced failures for PBGA packages.

The 1990s will be the decade of environmental awareness. Governments have introduced (or are about to introduce) eco‐labelling schemes for products and packages. However, assessing the environmental friendliness of packaging can be meaningful only if cognisance is taken of the six functions of packaging and the three environments where packaging has to perform. Categorising packaging as either good or bad based on whether or not it is recyclable or reusable is too simplistic an approach and could result in greater rather than fewer environmental problems.

Aims to present a finite element analysis based methodology for estimating the characteristic fatigue life of a solder joint interconnect under accelerated temperature cycling to predict the reliability performance of a flip chip package.

The method uses the ANSYSTM finite element analysis tool along with Anand's viscoplastic constitutive law. Darveaux's crack growth rate model was applied to calculate solder joint characteristic life using simulated viscoplastic strain energy density results at the package substrate and printed circuit board solder joints. Two package configurations are evaluated with the above methodology, with the first being a simplified flip chip model and the second being a detailed flip chip model. Each of these configurations is subjected to two accelerated temperature cycling tests.

Generally, the results indicate that the solder joint at the corner end of the package tends to fail first. The characteristic lives of solder joint at the package ball/board interface are 24‐46 percent higher than the characteristic lives of solder joint at the package ball/substrate interface. This means that the interface between the solder ball and substrate will fail first before the interface between the solder ball and the board.

Demonstrates that genetic algorithms can be used as tools to predict possible package dimensional values for given constraints on solder joint life.

Text retrieval software packages are designed to support the creation of textual rather than numerical, tabular or graphical databases. General trends concerning the nature of text retrieval software packages that run on microcomputers are analysed. A profile is drawn of the various features that can be expected of a text retrieval package, in order to build a picture of a typical package and to facilitate comparisons between packages. Factors that are considered are: price ranges, the length of time that packages have been available in the marketplace, contract and support, use and access, programming languages, outputs, retrieval facilities, interfaces and integrated modules. The market is shown still to be developing and changing.

Presents a new wire bondable land grid array (LGA) chip scale package called NuCSP. NuCSP is a minimized body size wire bondable package with rigid substrate interposer. The design concept is to utilize the plating bars on the edges of the package substrate as the wire bond fingers. Bond fingers are redistributed inward to an array of plated through hole vias underneath the chip, then are connected to copper pads on the bottom of the package. NuCSP package size is about equal to die size + 3 mm. Using conventional PCB substrate manufacturing with 4/4 mils routing width/space and wire bonding process, NuCSP offers a very low cost package suitable for memory chips and low pin count application specific IC (ASIC) applications. The other advantages are that the use of wirebonding allow NuCSP be applicable for die size, pad count and pitch variations. Because it is wire bondable, NuCSP may be as generic as plastic quad flat pack (PQFP), yet providing smaller body size, lower cost and smaller package electrical parasitic parameters.