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| 2. |
- Akbari, Saaed, et al.
(författare)
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Effect of PCB cracks on thermal cycling reliability of passive microelectronic components with single-grained solder joints
- 2019
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Ingår i: Microelectronics and reliability. - : Elsevier BV. - 0026-2714 .- 1872-941X. ; 93, s. 61-71
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Tidskriftsartikel (refereegranskat)abstract
- Lead-free tin-based solder joints often have a single-grained structure with random orientation and highly anisotropic properties. These alloys are typically stiffer than lead-based solders, hence transfer more stress to printed circuit boards (PCBs) during thermal cycling. This may lead to cracking of the PCB laminate close to the solder joints, which could increase the PCB flexibility, alleviate strain on the solder joints, and thereby enhance the solder fatigue life. If this happens during accelerated thermal cycling it may result in overestimating the lifetime of solder joints in field conditions. In this study, the grain structure of SAC305 solder joints connecting ceramic resistors to PCBs was studied using polarized light microscopy and was found to be mostly single-grained. After thermal cycling, cracks were observed in the PCB under the solder joints. These cracks were likely formed at the early stages of thermal cycling prior to damage initiation in the solder. A finite element model incorporating temperature-dependant anisotropic thermal and mechanical properties of single-grained solder joints is developed to study these observations in detail. The model is able to predict the location of damage initiation in the PCB and the solder joints of ceramic resistors with reasonable accuracy. It also shows that the PCB cracks of even very small lengths may significantly reduce accumulated creep strain and creep work in the solder joints. The proposed model is also able to evaluate the influence of solder anisotropy on damage evolution in the neighbouring (opposite) solder joints of a ceramic resistor.
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| 3. |
- Andersson, Dag, et al.
(författare)
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COSIVU - Compact, smart and reliable drive unit for fully electric vehicles
- 2016
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Ingår i: 2016 Pan Pacific Microelectronics Symposium (Pan Pacific). - : Institute of Electrical and Electronics Engineers Inc.. - 9780988887398
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Konferensbidrag (refereegranskat)abstract
- COSIVU is a three year collaborative research project that ended in September 2015 and which has been funded within the European Green Car Initiative (now the European Green Vehicle Initiative). COSIVU addresses one of the most critical technical parts in fully electrical vehicles (FEV) besides the energy storage system: the mechatronic drive-train unit. The COSIVU project has delivered a new system architecture for multiple wheel drive-trains by a smart, compact and durable single-wheel drive unit with integrated electric motor, full silicon carbide (SiC) power electronics (switches and diodes), a novel control and health monitoring module with wireless communication, and an advanced ultra-compact cooling solution. DfR utilizing FEM simulations ensures first time right solutions. This paper presents the main results including the architecture of the drive train solution as well as the modular design of the inverter based on Inverter Building Blocks, one per phase. Performance tests are presented here for the first time for both the heavy duty commercial vehicle solution performed in a test rig by Volvo, and the tests of the COSIVU solution adapted to a passenger car done by Elaphe.
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| 6. |
- Andersson, Dag, et al.
(författare)
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Smart access to small lot manufacturing for systems integration
- 2018
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Ingår i: 2018 Pan Pacific Microelectronics Symposium, Pan Pacific 2018. - 9781944543044 ; , s. 1-9
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Konferensbidrag (refereegranskat)abstract
- The three year EU project SMARTER-SI that ends in January 2018 has tested a new concept for small lot manufacturing for SMEs which we call the Cooperative Foundry Model (CFM). During previous research, all RTOs have completed building blocks, i.e. components or parts of systems which are readily available and characterized by their high Technology Readiness Level (TRL). These building blocks are combined and integrated in so-called Application Experiments (AEs), thereby creating innovative Smart Systems that serve the SMEs' needs. Four pre defined AEs have been presented before [1] and in this paper, six additional AEs will be presented: i) a smart sensor for pneumatic combined clutch and brakes, ii) smart well plates for tissue engineering integrating continuous, non-invasive TEER iii) microclimate sensor for moisture applications, iv) LTCC-Si-Pressure Sensor, v) miniaturized capillary electrophoresis system for bio analysis, and vi) a MEMS sensor module for respiratory applications. Finally, a brief description of ongoing standardization efforts is presented.
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| 7. |
- Andersson, Dag, et al.
(författare)
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SMARTER-SI - Smart access to manufacturing for Systems Integration
- 2017
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Konferensbidrag (refereegranskat)abstract
- The three year EU project SMARTER-SI that started in February 2015 has developed and tested a new production platform for smart systems that offer SMEs and “mid-cap” companies help to manufacture small and medium volumes. The ultimate goal of this project is to test a new concept for small lot production, which we call the Cooperative Foundry Model (CFM). The CFM is tested by combining components or parts of systems (building blocks) already developed by the RTOs involved in the project in so-called Application Experiments (AEs), thereby creating innovative Smart Systems which serve SMEs' product needs. During the first two years, four predefined AEs have been developed that consist of i) a multi-parametric point of care testing (POCT) device, ii) a dew-point measurement system, iii) a CO2 measurement system, and iv) a portable device that can be used to screen water quality.
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| 9. |
- Andersson, Eric, 1992, et al.
(författare)
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Nondestructive cleaning of the LaAlO3/SrTiO3 surface with ultraviolet light and ozone
- 2016
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Ingår i: Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics. - : American Vacuum Society. - 2166-2746 .- 2166-2754. ; 34:4
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Tidskriftsartikel (refereegranskat)abstract
- The effect of ultraviolet light produced ozone and irradiation (UV/ozone) cleaning on the surface properties and interface electrical properties of 4 unit cell (uc) LaAlO3/SrTiO3 samples is examined. A standard photolithography process is used to contaminate the samples which are then cleaned in UV/ozone. Atomic force microscopy measurements show that the photoresist contaminated samples can be cleaned efficiently using this method. The surface roughness of the cleaned samples is comparable to that of the as-grown samples. Furthermore, electrical transport measurements show that the mobility decreases and the sheet carrier density increases for the contaminated samples, which also display indications of an onset to the Kondo effect. By removing the contaminants with UV/ozone cleaning, the mobility and sheet carrier density can be partially restored toward the as-grown values. The mobility is increased by about two times from approximate to 1000 cm(2) V-1 s(-1) for the contaminated samples to approximate to 2000 cm(2) V-1 s(-1) for the ozone cleaned ones. (C) 2016 American Vacuum Society.
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| 10. |
- Andersson, Susanne, et al.
(författare)
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Moving with(in) normative firewalls : a dynamic approach to study gendered careers and innovation processes in the truck industry
- 2018
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Konferensbidrag (refereegranskat)abstract
- In this paper we explore how existing work place culture and gendered norms impact on the possibilities to work with so called ”norm-critical” innovation processes in an organisation. Norm-critical reflexivity in the context of innovation processes implies to pay attention to invisible and implicit norms that may result in that certain privileged perspectives is being prevailed (over others) (Balkmar & Lykke 2015). The empirical findings emanates from a two year interactive research project, in which gender researchers in collaboration with participants at Volvo Group, Sweden, have explored the ways that the company can increase its capacity to work with norm-critical perspectives in the innovation process. Volvo is a highly gender segregated organisation. At the same time the trucking industry in itself is highly masculinized in terms of different professions; ranging from truck drivers to sales personnel to technical engineers involved in the design and manufacturing of trucks. In later years the shortage of truck drivers, in combination with more women drivers entering trucking academies and haulage contractors, has led to a questioning of male norms in the transport business. This includes reports of difficult working conditions for female truckers, including how the design of the truck itself takes the male body as the implicit norm, to the assumption that it is a man that is the presumed driver of trucks.This paper focus on the part of the project that seeks to better understand how existing work-place culture and norms structure who is considered the ideal employee (Acker 1992) and its implications for innovation. This includes studying its impacts on both the possibility for different categories of employees to take part in the innovation work on equal terms, and the ability to reflect upon the impact of implicit norms in the innovation process itself. In total, 17 semi-structured interviews were conducted with co-workers and managers (13 women and 5 men). The main questions concerned whether there existed ideals that formed implicit ”codes” (Bendl and Schmidt 2010) in the organization and its impact on ideas of preferred professional qualifications, behaviors, personal qualities and its links to career possibilities and innovation. The underlying theoretical assumption is that gender is a fundamental element of organisational structure and work life; “present in [its] processes, practices, images and ideologies, and distribution of power” (Acker 1992, p. 567). The way that gender plays out in the daily life in a workplace is understood as not being a static barrier prohibiting women in general, rather, it is considered fluid, relational and may vary depending on the context (Meyerson & Fletcher 2001, Bendl and Schmidt 2010). It is argued that the concept ”fire wall” (Bendl and Schmidt 2010 ), offers a fruitful way to highlight the elasticity and permeability that we believe characterize the forms of discrimination, inclusion and exclusion that takes place in these processes.ReferencesAcker, J. 1992. Gendering Organisational Theory. In Mills, A. and Tancered, P. (eds.). Gendering Organisational Analysis. London: SAGE.Acker, J. 2006. Inequality Regimes: Gender, Class, and Race in Organisations. Gender and Society 20(4):441-464.Balkmar, D. & Lykke, N. 2015. Developing disruptive norm-critical innovation at Volvo: FINAL REPORT. Linköping: Tema Genus Report Series No. 23: 2015.Bendl, R. & Schmidt. 2012. From 'Glass Ceilings' to 'Firewalls' - Different Metaphors for Describing Discrimination. Gender, Work and Organization. Vol. 17. No 5:612-635.Meyerson, D. & Fletcher J.K. 2001. A Modest Manifesto for Shattering the Glass Ceiling. Boston: Harvard Business Review.
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