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1 – 6 of 6L. De Schepper, W. De Ceuninck, H. Stulens, L.M. Stals, R. Vanden Berghe and S. Demolder
A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method…
Abstract
A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method, referred to hereafter as the in‐situ method, allows measurement of the electrical resistance of a thick film resistor to a resolution of a few ppm during accelerated ageing. With the in‐situ technique, the electrical resistance measurements are performed at the elevated ageing temperature during the ageing treatment, whereas with the conventional ageing method the resistance measurements are carried out at room temperature, between subsequent annealing steps. The measuring resolution obtainable with the in‐situ method is orders of magnitude better than with the conventional method. The ageing kinetics can therefore be studied on a shorter time scale and in greater detail than with the conventional method. In this paper, the authors use the in‐situ method to study the accelerated ageing of the Du Pont HS‐80 thick film resistor system, encapsulated with a proper glaze. It will be shown that kinetics of the resistance drift observed in this system cannot be described by an Arrhenius‐type equation. The ageing data can only be interpreted in terms of a kinetic model incorporating a spectrum of activation energies for the ageing process. Such a model is given, and is shown to provide a good explanation of the observed ageing behaviour. The physical process that causes the observed ageing is most probably diffusion of silver from the contacting terminals into the amorphous matrix of the thick film resistor.
J.V. Manca, L. De Schepper, W. De Ceuninck, M. D'Olieslager, L.M. Stals, M.F. Barker, C.R. Pickering, W.A. Craig, E. Beyne and J. Roggen
In this paper, it is shown that the so‐called in‐situ electrical measurement technique is a valuable tool for understanding failure mechanisms in thick film dielectrics. The…
Abstract
In this paper, it is shown that the so‐called in‐situ electrical measurement technique is a valuable tool for understanding failure mechanisms in thick film dielectrics. The technique makes it possible to measure important electrical characteristics of thick film dielectric systems in the temperature range from room temperature up to 900°C. This information is essential to understand failure mechanisms and to optimise the system with respect to quality and reliability. Mainly two electrical properties have been investigated: (i) the electrical resistance of the dielectric as a function of temperature and (ii) the spontaneous electromotive force occurring at higher temperatures between two metal layers with the dielectric in between. A significant result of the work is the observation of a close correlation between the leakage current measured through the dielectric at elevated temperatures, and the ability of the dielectric to resist shorting and blistering effects during the preparation of circuits. Secondly, from in‐situ voltage measurements, it was confirmed that the mixed metallurgy system Au(bottom)‐dielectric‐Ag(top) acts at 850°C as a spontaneous battery, and the battery voltage (i.e., the spontaneous electromotive force) was measured. Depending on the type of dielectric, a battery voltage up to 200 mV between the two metal layers was observed. As a result of this spontaneous electromotive force, blistering occurs. The battery voltage was shown to be much smaller in unmixed metallurgy systems with Ag(bottom)‐dielectric‐Ag(top) or Au(bottom)‐dielectric‐Au(top). However, if an external voltage of 300 mV is applied to such a system during a temperature profile up to 850°C, blisters can also be induced. This shows unambiguously that blistering is a voltage driven effect.
Xingxing Li, Shixi You, Zengchang Fan, Guangjun Li and Li Fu
This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health…
Abstract
Purpose
This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health care. The purpose of this paper is to summarize the current state of the field, identify challenges and limitations and discuss future prospects for the development of saliva-based electrochemical sensors.
Design/methodology/approach
The paper reviews relevant literature and research articles to examine the latest developments in electrochemical sensing technologies for saliva analysis. It explores the use of various electrode materials, including carbon nanomaterial, metal nanoparticles and conducting polymers, as well as the integration of microfluidics, lab-on-a-chip (LOC) devices and wearable/implantable technologies. The design and fabrication methodologies used in these sensors are discussed, along with sample preparation techniques and biorecognition elements for enhancing sensor performance.
Findings
Electrochemical sensors for salivary analyte detection have demonstrated excellent potential for noninvasive, rapid and cost-effective diagnostics. Recent advancements have resulted in improved sensor selectivity, stability, sensitivity and compatibility with complex saliva samples. Integration with microfluidics and LOC technologies has shown promise in enhancing sensor efficiency and accuracy. In addition, wearable and implantable sensors enable continuous, real-time monitoring of salivary analytes, opening new avenues for personalized health care and disease management.
Originality/value
This review presents an up-to-date overview of electrochemical sensors for analyte detection in saliva, offering insights into their design, fabrication and performance. It highlights the originality and value of integrating electrochemical sensing with microfluidics, wearable/implantable technologies and point-of-care testing platforms. The review also identifies challenges and limitations, such as interference from other saliva components and the need for improved stability and reproducibility. Future prospects include the development of novel microfluidic devices, advanced materials and user-friendly diagnostic devices to unlock the full potential of saliva-based electrochemical sensing in clinical practice.
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The purpose of this paper is to investigate to what extent the initiatives of local governments to launch modernisation processes are facilitated by local autonomy, which is…
Abstract
Purpose
The purpose of this paper is to investigate to what extent the initiatives of local governments to launch modernisation processes are facilitated by local autonomy, which is increasingly important in both the theory and practice of public policy and management.
Design/methodology/approach
Local government reforms are distinguished according to the institutional structure at which they are directed and local autonomy is assessed as a multidimensional concept. Drawing on a multilevel analysis of the Swiss case, this paper combines data stemming from a survey conducted at the local tier with secondary data from the regional tier.
Findings
The main empirical findings are threefold. First, when local governments undertake managerial or political reform initiatives, their autonomy with respect to higher levels of government matters. Second, it is not local autonomy but rather the perception of structural problems that is the force driving territorial reforms. Third, it is not the autonomy enjoyed by local governments vis-à-vis local factors, but rather the pressures stemming from that context that may lead to reforms.
Originality/value
By adopting a comparative approach to local autonomy, this paper shows that local governments which have sufficient latitude for local policy making are likely to take initiatives to improve service delivery in accordance with local preferences.
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Susana Jorge, Maria Antónia Jorge de Jesus and Sónia P. Nogueira
The purpose of this paper is to research the use of accounting information by politicians. Based on the Portuguese Parliament setting, it seeks to understand how useful…
Abstract
Purpose
The purpose of this paper is to research the use of accounting information by politicians. Based on the Portuguese Parliament setting, it seeks to understand how useful politicians consider this information to be, what type of budgetary and financial information they use, and for what purposes. Finally, the research also seeks to find out whether politicians resort to expert intermediaries or advisors help them in the use of this information.
Design/methodology/approach
Following a qualitative and interpretative methodology, the study draws upon interviews with Members of Parliament in Portugal (and their technical advisors (TAs)) from all political parties, in particular the members of the Budget, Finance and Administrative Modernization Committee (COFMA) of the Parliament.
Findings
Research shows that, due to the general lack of knowledge and the complexity of the accounting information, politicians in the Parliament do not use it frequently, only occasionally. To be better or worse informed for the debates and other activities depends on each Member of Parliament’s personal willingness to prepare oneself, notwithstanding some aggregated and previously analyzed information made available by official technical support units. Parliamentarians may also resort to TAs, who prepare the information at their request. Both intermediaries and TAs are deemed important to support parliamentarians’ understanding of more technical budgetary and financial issues.
Practical implications
This paper shows that politicians acknowledge there is room for improving the role of information intermediaries and advisors, who would support them to better understand and use accounting information. Parliamentary groups incharge of hiring advisors, as well as accounting professionals, in Portugal and in other countries, must be aware of the very useful role accountants play in this process.
Social implications
While allowing to understand whether and how politicians use accounting information, this research contributes to the process of public sector accounting reforms in Portugal, and at an international level, inasmuch as public sector accounting and reporting standards should better address these users’ information needs. Assuming that these reforms would foster more accurate, transparent and useful information for accountability and decision making, it is essential that politicians acknowledge and become real users of accounting information, in order to accomplish those objectives.
Originality/value
This study contributes to the general knowledge of how politicians use accounting information. Academic studies so far have not gathered enough evidence about the type of accounting information that is actually important for politicians. This paper highlights that use of such information by politicians depends on individual skills and their willingness to receive the appropriate advice.
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Lotta-Maria Sinervo and Petra Haapala
The highest decision-making body in a municipality is the council, whose members are elected every fourth year. Therefore, local politicians are in the key position in using…
Abstract
Purpose
The highest decision-making body in a municipality is the council, whose members are elected every fourth year. Therefore, local politicians are in the key position in using financial information in decision making. The purpose of this paper is to study Finnish local politicians’ use of financial information.
Design/methodology/approach
This paper studies the speech of local politicians as they describe financial operations and financial position of the municipalities they represent. Here, the words of local politicians are considered an expression of their use of financial information. The use of financial information includes its impact on decision making. The focus is on the impact of different individual characteristics of financial information use in speech about financial operations and financial position. The paper employs qualitative empirical data collected through semi-structured thematic interviews with members of the Finnish local government. Data are analyzed with descriptive statistical methods.
Findings
Local politicians use financial information when they talk about financial operations and financial position of their municipality. Individual characteristics, such as political experience, affect the use of financial information. Experienced local politicians are familiar with financial information and use it more systematically than inexperienced politicians. Contrasted to expectations, financial expertise has a negative impact on financial information use. Moreover, in general, the ideology of politicians does not affect their use of financial information.
Originality/value
The paper sheds light on the value of individual characteristics of financial information use. It develops and tests hypotheses based on previous research on the impact of individual attributes of local politicians in the Finnish local government.
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