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Einleitung: Der Zuwachs des Wissens in der HNO-Heilkunde ubersteigt, wie in den anderen Disziplinen auch, seit langem die individuellen Moglichkeiten, dieses Wissen adaquat aufzunehmen und einen entsprechenden Uberblick zu behalten. Somit konnen tatsachliche oder vermeintliche Wissenslucken entstehen, die der Weiterentwicklung des Faches und einer evidenzbasierten Behandlung von Patienten entgegenstehen. Zudem gibt es in Kliniken und Praxen traditionelle Lehrmeinungen, die den medizinischen Alltag pragen, ohne dass diese Schulen je hinsichtlich ihrer Evidenz hinterfragt wurden. Methode: Zwischen Februar und Juni 2015 wurde unter 160 HNO-Kliniken, davon 34 Lehrstuhlinhaber, und 2 670 HNO-Praxen eine 2-armige Online-Umfrage zu vorhandenen oder empfundenen Evidenzlucken im Fachgebiet der HNO-Heilkunde mittels eines zuvor entwickelten Fragebogens durchgefuhrt. Dabei erfolgte die Befragung zur einen Halfte in offener Form, zur anderen Halfte wurde eine Systematik des Fachgebietes den Befragten als Orientierung zur Verfugung gestellt. Erganzt wurde die Befragung durch Zusatzangaben, wie der Anzahl von Publikationen und Forschungsschwerpunkten bei den Kliniken und dem Lebensalter und der Praxisform bei den niedergelassenen Kolleginnen und Kollegen. Ergebnisse: Bei den Kliniken gab es eine Rucklauferquote von 39,7%, bei der geschlossenen von 29,3%. Bei den Praxen antworteten 14,6% der geschlossen und 18,6% der offen befragten Arztinnen und Arzte. Grose Unterschiede ergaben sich zwischen den beiden Befragungsformen nicht. Bei den Kliniken fuhrten mit je etwa 30% otologische und onkologische Themen die Liste der Antworten an. Hierbei wurden zu aktuellen diagnostischen und therapeutischen Problemen, wie z. B. der stadiengerechten Tumortherapie oder bei implantierbaren Horhilfen, entsprechende Fragen formuliert. Der Schwerpunkt der aus den Praxen stammenden Fragestellungen lag bei diagnostischen Verfahren, z. B. bei speziellen, neuen Verfahren der Audiologie und Vestibulogie. Sowohl Kliniken als auch Praxen benannten aber auch alltagsrelevante Randgebiete des Faches. Diskussion: Im folgenden mussten die benannten Wissenslucken verifiziert bzw. falsifiziert werden und durch eine entsprechende Literaturrecherche geklart werden, ob die vorhandene Evidenz tatsachlich bei den Behandlern durch Leitlinien, Publikationen, Kongresse und Fortbildungen im Alltag ankommt. Weitere Schritte waren die Priorisierung der kunftigen Forschung, ein Evidenz-Mapping, die Entscheidung fur weitere systematische Reviews und gezielte Studien in Verbindung mit der Einwerbung von Drittmitteln und bei der Zusammenarbeit mit Patientenverbanden. Das so gewonnene Wissen sollte schlieslich in einer verbesserten Form in den klinischen Alltag transferiert werden. Hierzu sollten fur die Bereiche der Kliniken und Praxen jeweils die 10 wichtigsten Fragestellungen formuliert werden.

As in other disciplines, the burgeoning knowledge in ENT medicine long ago surpassed our ability to adequately absorb it and maintain a proper overview. This can give rise to actual or assumed knowledge gaps that can impede the progress of the discipline and evidence-based treatment of patients. Clinics and medical practices also hold to traditional doctrines that shape day-to-day medicine, without these schools being challenged based on evidence.Between February and June 2015, 160 ENT clinics, including 34 university hospitals, and 2,670 ENT practices took part in a two-arm online survey on existing or perceived evidentiary gaps in ENT medicine using a previously development questionnaire. The survey used for half the participants was open in form; the other half were given a closed survey with systematics of the field for orientation. The survey was augmented with additional data such as the number of publications and focus areas in the clinics and the age and type of practice of the established physicians.The return rate from the clinics was 39.7%; the return rate of the closed surveys was 29.3%. Of the physicians in medical practice, 14.6% responded to the closed and 18.6% to the open survey. There were no major differences between the two forms of survey. Otological and oncological issues comprised approximately 30% of the list of answers from clinics. Corresponding questions were formulated regarding the current diagnostic and therapeutic problems, such as with stage-related tumor treatment or implantable hearing aids. Diagnostic procedures, e.g., special new procedures in audiology and vestibulogy, dominated the surveys from the practices. However clinics and practices alike cited marginal areas of the discipline that are of daily relevance.The cited knowledge gaps then needed to be verified or refuted and clarified based on research of the literature as to whether the existing evidence actually reached healthcare providers in the form of guidelines, publications, conferences or continuing training for application in daily practice. Other steps would include prioritizing future research, evidence mapping, deciding on further systematic reviews, and targeted studies in conjunction with procuring third-party funding and in cooperation with patient associations. The knowledge thus gained should ultimately be transferred in improved form for application in daily clinical practice. Ten questions of key importance each needed to be formulated for the hospitals and practices.

Treating patients requires the inclusion of existing evidence in any health care decision, to be able to choose the best diagnosis or treatment measure or to make valid prognosis statements for a particular patient in consideration of the physician's own expertise.The basis are clinical trials, the results of which are ideally gathered in systematic reviews, rated, summarized and published. In addition to the GCP (Good Clinical Practice)-compliant planning, conducting and analysis of clinical studies it is essential, that all study results are made publicly available, in order to avoid publication bias. This includes the public registration of planned and discontinued trials.In the last 25 years, the evidence-based medicine (EbM) has increasingly found its way into clinical practice and research. Here EbM is closely associated with the names Archibald Cochrane and David Sackett. In Germany, both the German Cochrane Centre (DCZ) and the network of evidence-based medicine (DNEbM) were established approximately 15 years ago. In the international Cochrane Collaboration clinicians and other scientists like statisticians interdisciplinary work side by side to develop the methods of evidence-based medicine and to address the topics of evidence generation and processing as well as the transfer of knowledge. Challenge: Existing evidence primarily serves doctors to support their decision-making, but is also the basis for providing scientific proof for a health care intervention's benefit to patients and ultimately payers/health insurances. The closure of existing evidence gaps requires substantial human and financial resources, a complex organizational structure and can only succeed with the involvement of clinical and methodological expertise and specific knowledge in the field of clinical research. In addition, the knowledge must be transferred into practice, using journals, guidelines, conferences, databases, information portals with processed evidence and not least the medical education of students.One problem is the wealth of information, so that in clinical practice there may be gaps in knowledge of actual evidence. Usually it still takes several years until new knowledge is fully implemented in daily practice.The German Society of Otolaryngology, Head and Neck Surgery (DGHNOKHC) and the German professional association of otolaryngologists (BVHNO) have a vested interest in supporting their members in the generation, processing and dissemination of evidence, and to foster the transfer of knowledge into practice. This includes the areas of diagnosis, treatment, prognosis and prevention as well as drug therapies or the application of medical devices or surgical procedures. Crucial is the regular determination of existing evidence gaps, including in the area of already established procedures, which must be followed by a prioritization of research questions and subsequent conduct of clinical research. Only with combined efforts even large trials can be performed, to test therapies and diagnostics for example, also after approval under everyday conditions. Methods, Results and Vision: The executive committees of DGHNOKHC and BVHNO have together founded the German Clinical Trials Unit for Ear, Nose and Throat medicine, Head and Neck Surgery (DSZ-HNO) to assist their members in the identification of evidence gaps and the planning and conduct of systematic reviews and clinical trials. The first projects have been started, including a BMBF(German Ministry for education and research)-funded clinical trial for the treatment of sudden hearing loss and a survey to detect evidence gaps in Otolaryngology. It seems both reasonable and feasible to provide a structure such as a jointly-run study center for doctors in hospitals and medical practices to assist in clinical research and to anchor the principles of evidence-based medicine in daily life.

Systemic steroids are widely used worldwide as a standard of care for primary therapy of idiopathic sudden sensorineural hearing loss (ISSHL). The German ISSHL guideline recommends high-dose steroids for primary therapy of ISSHL, without evidence from randomized controlled trials (RCTs). The rationale for the treatment of ISSHL using high dose steroids is only based on retrospective cohort studies.This article describes the planning and initiation of a multicenter, national, randomized, controlled clinical trial entitled Efficacy and safety of high dose glucocorticosteroid treatment for idiopathic sudden sensorineural hearing loss - a three-armed, randomized, triple-blind, multicenter trial (HODOKORT). This clinical trial aims to compare standard dose with two types of high-dose steroids for primary systemic therapy with respect to their efficacy in improving hearing, and thus communication ability, in patients with idiopathic sudden sensorineural hearing loss.This study is funded by the "Clinical Trials with High Patient Relevance" research program in the health research framework of the German Federal Ministry of Education and Research. It is one of two studies by the German Study Center of Clinical Trials of the German Society of Otorhinolaryngology, Head and Neck Surgery (DSZ-HNO). Planning and initiation was done in cooperation with the DSZ-HNO, the Coordination Center of Clinical Trials of the Martin-Luther-University Halle-Wittenberg, and the Study Center of the University Hospital Freiburg.

Systemic steroids are widely used worldwide as a standard of care for primary therapy of idiopathic sudden sensorineural hearing loss (ISSHL). The German ISSHL guideline recommends high-dose steroids for primary therapy of ISSHL, without evidence from randomized controlled trials (RCTs). The rationale for the treatment of ISSHL using high dose steroids is only based on retrospective cohort studies.This article describes the planning and initiation of a multicenter, national, randomized, controlled clinical trial entitled Efficacy and safety of high dose glucocorticosteroid treatment for idiopathic sudden sensorineural hearing loss - a three-armed, randomized, triple-blind, multicenter trial (HODOKORT). This clinical trial aims to compare standard dose with two types of high-dose steroids for primary systemic therapy with respect to their efficacy in improving hearing, and thus communication ability, in patients with idiopathic sudden sensorineural hearing loss.This study is funded by the "Clinical Trials with High Patient Relevance" research program in the health research framework of the German Federal Ministry of Education and Research. It is one of two studies by the German Study Center of Clinical Trials of the German Society of Otorhinolaryngology, Head and Neck Surgery (DSZ-HNO). Planning and initiation was done in cooperation with the DSZ-HNO, the Coordination Center of Clinical Trials of the Martin-Luther-University Halle-Wittenberg, and the Study Center of the University Hospital Freiburg.

Um Informationen zu allen klinischen Studien in Deutschland zu bundeln und so allen Interessengruppen die Suche nach geplanten, laufenden und abgeschlossenen Studien zu erleichtern, wird in enger internationaler Abstimmung mit der WHO das Deutsche Register Klinischer Studien (DRKS) aufgebaut. Das DRKS ist ein kostenfreies, offentlich zugangliches Online-Register, das allen Nutzern die Moglichkeit bietet, Informationen uber klinische Studien in Deutschland zu suchen oder anderen eigene Studien uber die Registrierung zuganglich zu machen. Das Projekt wird vom Bundesministerium fur Bildung und Forschung (BMBF) gefordert und am Institut fur Medizinische Biometrie und Medizinische Informatik des Universitatsklinikums Freiburg als gemeinsames Projekt des Zentrums Klinische Studien Freiburg und des Deutschen Cochrane Zentrums implementiert. Seit Oktober 2008 ist das DRKS als WHO-Primar-Register anerkannt und erlaubt damit die ICMJE- (International Committee of Medical Journal Editors-)konforme Registrierung klinischer Studien. Im vorliegenden Beitrag werden die Grunde fur den Aufbau eines nationalen Studienregisters, technische und inhaltliche Aspekte bei der Implementierung sowie die Einbettung in den nationalen und internationalen Zusammenhang beschrieben.

Objective It is a moral responsibility towards patients, funding organizations, the scientific community and the general public to publish not only the results of clinical trials but also to inform prospectively about planned trials. This is especially important for scientists, funding organizations, and ethics committees, since they are involved in the planning of new trials, which should rely on the knowledge of existing trials. Moreover, patients can only participate in clinical trials if they or their physicians are aware of ongoing trials for which they are eligible. In order to provide a central portal for information on clinical research in Germany and to facilitate the search for specific trials, the German Clinical Trials Register was implemented in 2008. Method An internet-based prototype of the German Clinical Trials Register was developed in close co-operation with the World Health Organization's registries network on the basis of the internationally harmonized data specification. This was further adapted to a bilingual registry's needs. Co-operation with medical ethics committees in Germany has been initiated with the aim of a joint synergistic data acquisition procedure. Results The German Clinical Trials Register was launched in August 2008. It was approved as the World Health Organization's primary registry for Germany in October 2008, and fulfils the requirements of the International Committee of Journal Editors. Conclusion The German Clinical Trials Register provides a central bilingual portal for all users (including scientists, patients, physicians, funding organizations, and ethics committees) for information on planned, ongoing, and completed clinical trials conducted in Germany. The German Clinical Trials Register allows International Committee of Journal Editors and World Health Organization-compliant registration of clinical trials in Germany.

Die Weltgesundheitsorganisation WHO formuliert auf ihrer Internetseite klar die wissenschaftliche, ethische und moralische Verpflichtung zur Studienregistrierung. Studienregister stellen Informationen uber geplante, laufende und abgeschlossene Studien anhand eines standardisierten Datensatzes der Allgemeinheit zur Verfugung. Die Gruppe der Nutzer von Studienregistern ist ebenso heterogen wie die Grunde fur eine transparente Darstellung der klinischen Forschung. Unter ethischen Gesichtspunkten ist eine Registrierung aller klinischen Studien unerlasslich. Gesunde Probanden und vor allem Patienten nehmen an einer Studie nicht nur in Erwartung eines personlichen Nutzens teil, z. B. in der Hoffnung, von neuartigen Therapiemoglichkeiten zu profitieren, sondern auch, um zum medizinischen Fortschritt beizutragen. Dies setzt voraus, dass die Ergebnisse der Studien bekannt sind und in die Behandlung von Patienten in den klinischen Alltag oder die weitergehende Forschung Einzug halten. Viele Studien haben aber gezeigt, dass nur ca. 50 % aller Studienergebnisse in der Literatur veroffentlicht werden, was zu einer verzerrten Wahrnehmung und Bewertung der vorhandenen Evidenz zu Fragestellungen der Diagnose, Pravention und Therapie fuhrt. Die fehlende Transparenz behindert damit nicht nur die Umsetzung von Erkenntnissen in die Praxis, sondern bedingt auch redundante Forschung und fuhrt damit zu einer Verschwendung von Ressourcen sowie einem ungerechtfertigten Einschluss von Teilnehmern in Studien.

In this paper, benchmark calculations are carried out using the FEM code ADINA. Three drop tests with a DCI cask carried out in Japan are investigated. The drop orientations comprise the 9 m drop with impact flat onto the cylindrical shell of the shock absorbers at the top and bottom part as well as the 1 m drop with impact of the bar in the center of the cylinder wall. Calculated results are compared to the experimental ones. It is found that the calculations meet the measurements conservatively.

The design assessment concerning the mechanical behaviour of transport and storage casks for radioactive material to fulfil nuclear safety criteria has to be based on two essential considerations: (1) Effective analysis of the stress–strain state of the cask components under both normal operational and test conditions including hypothetical accident scenarios with suitable accepted methods. (2) Economic estimation of the required properties and the structural state of the cask components with sufficient exactness. In an overview of the codes which are available at GNS/GNB for cask impact strength analyses (ANSYS, ADINA, VDI Codes), procedures and aspects of benchmarking and validation of calculation codes are described. The results of experimental full size cask drop test programs (CASTOR, POLLUX) and corresponding pre-test calculational analyses show the suitability of the codes used. The influence of dynamic effects on the mechanical properties of material (ductile cast iron, wood) has been inv...

Wooden impact limiters are used to reduce the forces acting on packages for irradiated fuel assemblies in hypothetical accident situations. For spruce specimens designed corresponding to the filling of real impact limiters, the dynamic force-compression characteristic has been evaluated in experiments according to the IAEA 9 m drop. Force-compression curves have been obtained, which are compared with those of equivalent static experiments. An analytical and a finite element approach have been used in combination with the dynamic compression curves to calculate the maximum cask deceleration and the maximum impact limiter deformation for a 9 m drop in an end-on, a side and an edge impact. The results are compared with those of 9 m drop experiments performed on original casks. An agreement between calculation and experiment has been found.

In this paper, criteria for the verification of numerical results for type B tests are proposed. Furthermore, some well-known commercially available FEM codes are investigated by analysing benchmark problems especially designed for transport packaging and by analysing drop tests experimentally performed on an original transport and storage cask. The results are checked by the proposed verification criteria and are found to be reliable.

Residual stresses play a prominent role in the fracture process of bimaterials and therefore knowing these stresses prior to failure is important for understanding the mechanical behaviour of bimaterials. A critical assessment has been made of three methods for determining the residual stresses. These methods are: stress optical measurement, indentation method, and finite element method. With stress optical measurements the difference in the principal normal stresses, Δσ, can be determined. In the centre region adjacent to the interface, the measured stress values are in agreement with results from a simple analytical formula for the normal residual stresses parallel to the interface. Surface stresses at arbitrary locations can be obtained by the usual indentation technique. At the surface, stresses perpendicular to the interface are dominant and have the opposite sign to the stresses parallel to the interface. When there is no mechanical mismatch between the components the magnitude of the residual stresses can be estimated with the above-mentioned formula. Two-dimensional plane strain finite element calculations are in good agreement with the stress optical measurements.

Non-singular T-stresses have been shown to influence small scale yielding (1) and crack paths for curved cracks (2). Thermal residual stresses and remote mixed-mode loading are principal sources of T-stress in composites (3). T-stress acting parallel to a bimaterial interface has been derived explicitly for the case in which the free surface perpendicular to the interface is prevented from contracting parallel to the interface (4). The role of thermal residual stresses was analyzed in (5) to study crack kinking out of the interface for a layered type of composite. Geometry functions arising from thermal residual stresses in interfacially cracked bimaterials have also been recently obtained (6,7).

The Ruffner collection, a Late Period (AD 500–1800), northern California skeletal sample, was analyzed for osteopathology. A probable fifth-finger dislocation of the right first and second phalanx was observed in a female aged 25–35 years at death. Traumatic adduction forced the second and third phalanges to slip laterally, upward and back about 10 mm, upon the dorsal surface of the first phalanx. Apparently, the medial collateral ligament of the interphalangeal joint was torn, making reduction impossible. As a result of the luxation, the flexor digitorum profundus slipped laterally and was fixed along the lateral surface of the distal end of the first phalanx. Over time, fusion of the joint restricted the flexion movement and left an abnormally aligned finger.

Layered composites develop thermal residual stresses during cooling from processing temperature to room temperature. The thermal stresses reduce fracture toughness data measured in four-point bending tests. To obtain a material parameter characterizing the interface fracture toughness the measured data must be corrected for the influence of thermal stresses. Thermal stresses often lead to kinking of an interface crack out of its initial plane. This tendency can be quantified by two parameters: (i) the ratio G/G0 of the energy release rate of the kinked crack G and the energy release rate of the interface crack GO and (ii) the ratio of the local stress intensity factors at the tip of the interface crack, KII/KI. Both quantities have been computed for a variety of material combinations using the finite element method. They are found to be strongly affected by thermal and elastic mismatch. Fracture experiments have been performed using brittle glass/glass composites with different thermal mismatched. The obtained fracture toughness values and crack deflection angles have evaluated on the basis of the numerical results. Measured and calculated kinking angles are in excellent agreement. The contribution of residual thermal stresses to the interface fracture toughness Kc has been elaborated.

It is a moral responsibility of those performing clinical studies towards patients, funding organizations, the scientific community and towards the general public to publish the results of clinical trials. Under-reporting of clinical trials with null or even negative results as well as over-reporting of trials with positive results can lead to a biased assessment of (new) treatments, which leads to overestimation of potential benefits and underestimation of potential risks. Comprehensive, publicly accessible clinical trial registries are now widely accepted as an essential tool to fill the information gap. Here, the background for implementing a clinical trials register in Germany is described, whereby publication bias, in particular, is addressed.

In order to provide a central portal for information on clinical research in Germany and thus to facilitate the search of planned, ongoing and completed clinical trials, the German Clinical Trials Register (GermanCTR) was implemented in cooperation with the WHO's registries network. It is an open access online register of clinical trials conducted in Germany, which allows all users to search for, register and share information on clinical trials. The project is funded by the Federal Ministry of Education and Research and is implemented at the Institute for Medical Biometry and Medical Informatics of the University Medical Center Freiburg as a joint project of the Clinical Trials Center Freiburg and the German Cochrane Center. Since October 2008 the GermanCTR is an approved WHO Primary Registry and allows clinical trial registration in Germany according to the requirements of the International Committee of Medical Journal Editors (ICMJE). Reasons for a national trials register, general and technical aspects of implementing the GermanCTR as well as the national and international integration are described here.

The European Union's so called Clinical Trials Directive 2001/20/EC was implemented in national law in Germany in August 2004, leading to the 12th amendment of the German Drug Law (Arzneimittelgesetz). The directive is intended to harmonize the clinical trial's regulatory environment across the European Union and to improve protection of human subjects. It lays down the principles and guidelines of Good Clinical Practice (GCP). As the regulation applies to all clinical trials on medicinal products for human use, and as only non-interventional studies are excluded, academic, investigator-initiated clinical trials will also have to comply with the EU clinical trials directive implemented in the German Drug Law. In an investigator-initiated trial in which the investigator takes the responsibility of a sponsor, the investigator-sponsor must take total legal and financial responsibility for the clinical trial. Since publicly funded clinical trials make a large contribution to improved care, concern has been expressed that non-commercial research projects will be reduced and the vital medical research conducted at academic institutions curtailed. Nonetheless GCP ensures a valid study design, qualified data management, analysis and monitoring of the trial and thereby promotes more valid data and protection of study participants. The trials are more likely to lead to reliable results leading to new therapies, strategies or a better understanding of diseases. What is needed, therefore, is an increase in public funding and the establishment of clinical trial units/organizations associated with the universities or hospitals where independent researchers have the possibility to obtain theoretical advice and practical help, professional training and support. In the end, the directive may serve as a stimulus to build a better national research environment and to promote public funding, and may lead to fewer but more valid clinical trials.

Continuous biotechnical development and rapid increase in knowledge in the field of research on human gene transfer raise scientific, medical, and ethical considerations in the scientific community and general public. Dissemination of new scientific findings is needed. Gene transfer studies today not only focus on monogenic diseases or life-threatening conditions such as cancer, but also comprise trials for diagnosis and prophylaxis and common medical conditions such as cardiovascular disease. This raises special attention and public discussion and requires even more the systematic monitoring and assessment of clinical trails being conducted. Whereas the number of gene transfer trials in the USA can be clearly specified, this had not been possible in Germany prior to the establishment of the DeReG database. The aim is implementation of a permanent registry comprehending all clinical gene transfer trials being conducted in Germany. Only a complete and updated database serves as a common foundation of knowledge for various groups and facilitates addressing scientific projects.

Die fortschreitenden technischen Entwicklungen und der rasche Wissenszuwachs auf dem Gebiet des somatischen Gentransfers am Menschen werfen wissenschaftliche, medizinische und ethische Fragen auf, die zu einem erhohten Informationsbedurfnis in der wissenschaftlichen Gemeinschaft und der interessierten Offentlichkeit fuhren und eine Vermittlung der gewonnenen Erkenntnisse notig machen. Inzwischen hat sich der Indikationskreis des somatischen Gentransfers uber monogene Erbkrankheiten und die Behandlung terminal erkrankter Krebspatienten hinaus auf so genannte „Volkskrankheiten“, wie z. B. kardiovaskulare Erkrankungen, sowie auf praventive Impfungen ausgedehnt, was auf der einen Seite das Interesse aus der Bevolkerung wachsen lasst und auf der anderen Seite eine systematische Begleitung und Bewertung der klinischen Studien umso mehr erforderlich macht. Wahrend die Zahl der in den USA durchgefuhrten Gentransferstudien genau beziffert werden kann, war dies in Deutschland vor Einfuhrung des Deutschen Registers fur somatische Gentransferstudien (DeReG) nicht moglich. Das Ziel des Registers ist die dauerhafte Etablierung einer Datenbank, in der alle in Deutschland durchgefuhrten klinischen Gentransferstudien registriert sind. So ist gewahrleistet, dass eine Datenbasis zur Verfugung steht, die nicht nur unterschiedlichen Interessengruppen als Informationsgrundlage dient, sondern auch wissenschaftliche Fragestellungen beantworten hilft.

Solder are used extensively in both die-attach and component attach in the first and second levels of electronic packaging. With the commercialization of VLSI and ULSI devices, both levels of fabrication have encountered difficulties in both manufacturability and reliability. These problems are analyzed and a novel solution of Z-axis, 'stress-free', and thermally conductive adhesives are introduced. The adhesive system has been engineered to simulate all the desirable characteristics of soldering such as fast 'curing' speed (milliseconds), ambient storage, low thermal and low electrical contact resistances, and reworkability. The drawbacks of solders, such as fatigue failures, stress-induced failures, and bridging, are avoided. All of these basic properties and some of the applications are discussed. >

The functional analysis of adhesives in microelectronics is considered. The authors then address the thermally induced stress on the microelectronic product at all levels of packaging, with major emphasis on component and substrate levels. They demonstrate various ways of reducing or eliminating this stress, which is a major cause of device failure. One of the proven methods is through the use of low T/sub g/ epoxies with high thermal stability. Attention is given to thermal management in connection with multichip modules. >