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L. 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…
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…
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.
J. Lantairès, B.C. Waterfield, H. Binner, G. Griffiths and Maurice Wright
ISHM invites papers for the above Conference, to be held on 29–31 May 1991 in Rotterdam, The Netherlands. Papers should cover areas such as: design, manufacturing…
ISHM invites papers for the above Conference, to be held on 29–31 May 1991 in Rotterdam, The Netherlands. Papers should cover areas such as: design, manufacturing, packaging and interconnection, materials and processing, applications, reliability, components, new technologies, marketing and economics, optoelectronics. Summaries should be in English, length 200–300 words. The deadline for receipt of summaries is 30 September 1990. (For full details, see announcement on pp. 54–55.)
Xiaodong Zhou, Huaqiang Shi, Xun Fu, Danmei Wu and Zhengshui Hu
The purpose of this paper is to investigate the tribological properties of MoS2 nano‐sized hollow spheres in liquid paraffin (LP) and the corresponding action mechanism…
The purpose of this paper is to investigate the tribological properties of MoS2 nano‐sized hollow spheres in liquid paraffin (LP) and the corresponding action mechanism. Morever, its feasibity of industrial application as an oil additive in the industrial lubrication field is also explored.
The tribological properties of MoS2 nano‐sized hollow spheres (NH‐MoS2) modified by Cyanex 301(di‐(2,4,4‐trimethylpentyl) dithiophosphinic acid) with size of 200 ∼ 300 nm in LP are studied and compared with those of the commercial colloidal MoS2 (CC‐MoS2) on a four‐ball tester and an Optimol SRV Oscillating friction and wear tester in a ball‐on disk configuration. The worn surfaces of the lower flat disc are examined with a scanning electron microscopy and an X‐ray photoelectron spectroscopy, respectively.
Results show that NH‐MoS2 is a better extreme‐pressure additive and anti‐wear (AW) and friction‐reducing additive in LP than CC‐MoS2. Under the optimum concentration of 0.5 per cent for both NH‐MoS2 and CC‐MoS2 and the load of 400 N, the friction coefficient of NH‐MoS2 + LP and CC‐MoS2 + LP decreases about 43.8 and 6.3 per cent, and the wear volume loss decreases about 60.3 and 12.0 per cent compared with the pure LP. The boundary lubrication mechanism for NH‐MoS2 + LP can be deduced as the effective chemical adsorption protective film formed by the long chain alkyls R and active elements (S and P) in the modification layer and tribochemical reaction film containing the tribochemical products of the additive. Moreover, sliding and rolling frictions co‐exist in NH‐MoS2 + LP, doing contributions to the good tribological properties as well.
In this paper, the Cyanex 301‐modified MoS2 nano‐sized hollow spheres with diameter of 200 ∼ 300 nm are firstly added into LP to investigate its tribological properties. The excellent AW and friction‐reducing properties indicate that this MoS2 hollow spheres product is a good oil additive, and the fundamental data presented here will be useful for its further industrial application in the future.
Polyisobutylene for pickling tanks. In order to increase corrosion resistance of pickling tanks, an underlayer of polyisobutylene, Soviet mark PSG and 3 mm. thick, is…
Polyisobutylene for pickling tanks. In order to increase corrosion resistance of pickling tanks, an underlayer of polyisobutylene, Soviet mark PSG and 3 mm. thick, is recommended, in place of the usual two layers of rubber, followed by a layer of acid‐resistant slab and a brick lining of half‐brick thickness, using diabasic cement. Details are tabulated of six different types of rubber undercoating as hitherto used. The new form of lining is claimed to be 10 to 15% lower in cost and its weight is also in most cases less, it may be used for tanks of 4 to 8 cu.m. It is suggested that some form of grooved silicate material might be of advantage in reducing total thickness of lining and its cost, but such material is not yet made in the Soviet Union on an industrial scale. For painting the outside shell, perchlor‐vinyl lacquers are suggested: one ground coat of KhSG‐26 (to Soviet standard or GOST 7313–55) and two coatings of KhSL (to same standard). —(V. L. Vinarskii, Stal' (Steel), 1957, 17 (3), 272–273.)
Gives an in depth view of the strategies pursued by the world’s leading chief executive officers in an attempt to provide guidance to new chief executives of today…
Gives an in depth view of the strategies pursued by the world’s leading chief executive officers in an attempt to provide guidance to new chief executives of today. Considers the marketing strategies employed, together with the organizational structures used and looks at the universal concepts that can be applied to any product. Uses anecdotal evidence to formulate a number of theories which can be used to compare your company with the best in the world. Presents initial survival strategies and then looks at ways companies can broaden their boundaries through manipulation and choice. Covers a huge variety of case studies and examples together with a substantial question and answer section.
The lengthy review of the Food Standards Committee of this, agreed by all public analysts and enforcement officers, as the most complicated and difficult of food groups…
The lengthy review of the Food Standards Committee of this, agreed by all public analysts and enforcement officers, as the most complicated and difficult of food groups subject to detailed legislative control, is at last complete and the Committee's findings set out in their Report. When in 1975 they were requested to investigate the workings of the legislation, the problems of control were already apparent and getting worse. The triology of Regulations of 1967 seemed comprehensive at the time, perhaps as we ventured to suggest a little too comprehensive for a rational system of control for arguments on meat contents of different products, descriptions and interpretation generally quickly appeared. The system, for all its detail, provided too many loopholes through which manufacturers drove the proverbial “carriage and pair”. As meat products have increased in range and the constantly rising price of meat, the “major ingredient”, the number of samples taken for analysis has risen and now usually constitutes about one‐quarter of the total for the year, with sausages, prepared meats (pies, pasties), and most recently, minced meat predominating. Just as serial sampling and analysis of sausages before the 1967 Regulations were pleaded in courts to establish usage in the matter of meat content, so with minced meat the same methods are being used to establish a maximum fat content usage. What concerns food law enforcement agencies is that despite the years that the standards imposed by the 1967 Regulations have been in force, the number of infringements show no sign of reduction. This should not really surprise us; there are even longer periods of failures to comply; eg., in the use of preservatives which have been controlled since 1925! What a number of public analysts have christened the “beefburger saga” took its rise post‐1967 and shows every indication of continuing into the distant future. Manufacturers appear to be trying numerous ploys to reduce the content below the Regulation 80% mainly by giving their products new names. Each year, public analysts report a flux of new names and ingenious defences; eg, “caterburgers” and similar concocted nomenclature, and the defence that because the name does not incorporate a meat, it is outside the statutory standard.
Roos Stals, Albert Dijkhuizen and Tom Joosten
GGzE, a mental health care organisation in the south Netherlands, implemented treatment for patients with severe personality disorders and substance use: clinical case…
GGzE, a mental health care organisation in the south Netherlands, implemented treatment for patients with severe personality disorders and substance use: clinical case management (CCM). CCM is a special healthcare facility for patients whose needs do not match other existing treatment designs. These patients are characterised by unproductive or disturbed relationships and multiple crises that deregulate clinical practice and impede recovery. In the CCM team, patients are treated with the theoretical concepts of relationship management, interpersonal reconstructive therapy, Livesley's stage‐wise treatment and integrated dual disorder treatment (IDDT). These theoretical models and methods used within CCM have been described extensively, though there has been no clinical study about its effect within GGzE so far. Professionals working within the CCM team report that behaviour such as acting out is reduced after about one year of treatment, with less interventions from other caretakers or police involvement. To substantiate these claims, a single group pre‐test and posttest was conducted to find out whether these patients really experience changes in physical and psychological problems, as well as changes in their personality disorder.The sample consists of patients who started treatment between 2004 and 2009 (pre measurement T=0), (n = 21). At T=0, patients completed the Symptom Checklist (SCL‐90) and Personality Characteristics Questionnaire (Vragenlijst Kenmerken Persoonlijkheid, VKP). The outcomes are compared with the results of the same questionnaires that were completed by patients in 2010 (post measurement T=1). The outcomes of the SCL‐90 show significant changes for fear, depression, hostility, distrust and interpersonal sensitivity, as well as the total score of psychoneurosis. The VKP shows significant changes for general personality disorder, schizoid personality disorder and borderline personality disorder. More research is needed to find stronger evidence of treatment effects of CCM, using a bigger sample, a control group and more outcome measurements that also include the drug use of patients.
In a recent issue of the Municipal Journal there appeared a short but apparently inspired article on the subject of London Government, in which is foreshadowed another…
In a recent issue of the Municipal Journal there appeared a short but apparently inspired article on the subject of London Government, in which is foreshadowed another drastic and apparently imminent alteration of the system of local administration at present in operation in the Metropolis.