This master´s thesis deals with QFN packages soldering and technology procedures optimization. The aim of theoretical part is description of QFN packages, their assembly and reflow soldering on PCB in HONEYWELL. The aim of the practical part is to propose a method of measuring temperature and optimizing the thermal profiles of selected PCB with QFN packages by using convection (HONEYWELL) and infrared (BUT) reflow ovens. Comparison and evaluation of thermal profiles for 3 production PCBś with QFN packages using solder paste AIM NC257-2 were realised. The main part of master´s thesis are appearance evaluation of solder joints, preparing microsection and measuring intermetallic layers thickness by using the optical and the scanning electron microscopes, analysation and study of QFN defects created during soldering proces. These tests were performed with 2 production PCB´s. Optimization of SPI and soldering technology procedures where were analyzed QFN packages were processed on one type of PCB. Interesting part of this diplomma thesis is creating of the 3D heat transfer model of QFN package during the reflow soldering in SolidWorks.

Semester project deals with the theoretical processing of reflow soldering. Describes the process of reflow soldering, description of intermetallic compounds, the influence of heating factor on the reliability and strength of soldered joints.Also deals with the preparation of cross-section, X-ray control, thermal cycling and description of test boards.

La première partie de cette thèse porte sur l'étude du no-reflow ou obstruction microvasculaire en IRM cardiaque. Dans une première étude, nous avons mesuré l'incidence du no-reflow dans une population de 25 patients pris en charge pour infarctus du myocarde sans sus-décalage du segment ST. Nous avons trouvé que 32% de ces patients présentaient un no-reflow et que la présence de no-reflow était associée à une taille d'infarctus significativement plus importante ainsi qu'une élévation plus importante des enzymes cardiaques. Dans une deuxième étude nous avons comparé la performance diagnostique du myocardial blush grade (MBG) pour le diagnostic du no-reflow avec l'IRM cardiaque sur les séquences de rehaussement tardif post-gadolinium. Cette étude a été réalisée dans une population de 39 patients pris en charge pour un premier épisode de STEMI. Nous avons trouvé que le MBG sous-estimait la présence de no-reflow à la phase aiguë de l'infarctus après reperfusion optimale en comparaison avec l'IRM. La deuxième partie de cette thèse concerne la quantification de l'infarctus du myocarde en IRM cardiaque de rehaussement tardif post-gadolinium. Nous avons comparé une technique d'évaluation semi-quantitative visuelle rapide avec la planimétrie manuelle classique sur une population de 103 patients pris en charge pour syndrome coronarien aigu. La taille de l'infarctus était évaluée par ces deux méthodes en IRM cardiaque réalisée 4 jours après admission. Nous avons trouvé une excellente corrélation et un bon niveau de concordance entre les deux méthodes d'évaluation de la taille d'infarctus, avec des temps de posttraitements beaucoup plus courts pour l'analyse visuelle rapide. Enfin, la troisième partie de cette thèse aborde le sujet de l'utilisation de l'IRM cardiaque comme outil de mesure dans les essais thérapeutiques sur la reperfusion myocardique. Nous avons utilisé l'IRM cardiaque pour évaluer l'efficacité de l'utilisation de la cyclosporine A à la phase aigüe de l'infarctus reperfusé et son effet sur remodelage ventriculaire à 6 mois. Dans cette étude 28 patients ont été étudiés en IRM cardiaque 5 jours et 6 mois après un infarctus du myocarde. Nous avons trouvé une persistance de la réduction significative de 23% de taille de l'infarctus à 6 mois dans le groupe traité par cyclosporine par rapport au groupe contrôle. Il n'y avait pas d'effet négatif de la cyclosporine A sur le processus de remodelage ventriculaire gauche / We assessed the presence and extent of microvascular obstruction (MVO) and its relationship with infarct size and left ventricular (LV) functional parameters after acute non-ST elevated myocardial infarction (NSTEMI). 25 patients with first acute NSTEMI underwent a complete cardio magnetic resonance (CMR) study 72 hours after admission. MO was detected in 32% of patients and was significantly associated with a larger infarct size. There were no significant difference between both groups for the LV functional parameters but patients with MO showed a higher troponin-I and CK release. We studied the relation between Myocardial Blush Grade (MBG) and gadolinium-enhanced CMR for the assessment of MVO in 39 patients with acute ST elevated myocardial infarction (STEMI) treated by primary PCI. No statistical relation was found between MBG and MVO extent at CMR (p=0.63). MBG underestimates MVO after an optimal revascularization in AMI compared to CMR.We compared the performance and post-processing time of a global visual scoring method to standard quantitative planimetry and we compared both methods to the peak values of myocardial biomarkers. 103 patients admitted with reperfused AMI to our intensive care unit had a complete CMR study 4±2 days after admission. There was an excellent correlation between quantitative planimetry and visual global scoring for the hyperenhancement extent’s measurement (r=0.94; y=1.093x+0.87; SEE=1.2; P<0.001) and there was also a good concordance between the two approaches with significantly shorter mean post-processing time for the visual scoring method. There was also significant levels of correlation between the enzymatic peak values and the visual global scoring method. The visual global scoring method allows a rapid and accurate assessment of the myocardial global delayed enhancement. This study examined the effect of a single dose of cyclosporine A used at the time of reperfusion, on LV remodeling and function by cardiac magnetic resonance (CMR) in the early days and 6 months after AMI.28 patients of the original cyclosporine A study had an acute (day 5) and a follow-up (6 months) CMR study. There was a persistent 23% reduction of the absolute infarct size at 6 months without any dementrial effect in the cyclosporine A group compared with the control group of patients. Cyclosporine A used at the moment of AMI reperfusion persistently reduces infarct size and does not have a detrimental effect on LV remodeling

La miniaturisation des systèmes d'imagerie présente aujourd'hui un fort potentiel dans plusieurs domaines, dont le développement de nouveaux dispositifs biomédicaux. Les exigences associées concernant l'imagerie demandent un effort substantiel dans le développement de composants optiques de haute qualité. Un meilleur contrôle de la propagation de la lumière ou de ses caractéristiques dans de tels systèmes est également important. Les composants doivent donc, par exemple, contenir les aberrations optiques pouvant affecter la résolution, la mise en œuvre de composants optiques dont le profil de phase continu est bien contrôlé est une voie intéressante. Ces composants devraient, de plus, être réalisés à partir de matériaux robustes en vue de leur assemblage au sein de dispositifs miniatures. Ce manuscrit de thèse de doctorat porte donc sur la conception et la fabrication parallèle de tels micro-composants optiques réfractifs réalisés en verre. Dans ce but, deux technologies ont été étudiées et optimisées, la lithographie à niveaux de gris et un procédé de soufflage de verre. En exemple, des microaxicons en verre ont été fabriqués et la génération de faisceaux de Bessel démontrée. Ce type de faisceau est caractérisé par une longue distance de propagation non-diffractive le long de l'axe optique, suivie d'une forme de faisceaux creux, qui les rend très utiles dans de nombreux domaines. Ces travaux de thèse ont été soutenus par le projet SMYLE (Small Systems for a Better Life) et le conseil Régional de Franche-Comté. / Miniaturization of imaging systems shows nowadays a strong potential for many applications, in particular, e. g., for novel biomedical devices. Related imaging specifications require a substantial effort onto the development of high quality microoptical components. better control of light propagation and features in such system sis also of particular interest. Components should then e.g. contain optical aberrations in order to reach high resolutions. In purpose of searching higher diffraction efficiencies or resolutions, optical components with well-controlled continuous phase profiles are sought. In addition, they also should be made of robust materials to handle their further assembly into miniaturized devices. Consequently, the manuscript focuses on the design and the parallel fabrication of such microoptical components made of glass. To that end, two technologies have been studied and optimized, namely gray-scale lithography and glass-blowing processes. As an example, glass-based microaxicons have been fabricated and Bessel beams generation has been demonstrated. This type of beam exhibits a long non-diffractive propagation distance along the optical axis followed by a dark hollow shape which makes them useful in many different applications. This work has been supported by the SMYLE (Smart Systems for a Better Life) European project and the Ranche-Comté Regional Council.

Graduation thesis is specialized on dilemma of the integrated circuits with ball grid array. Chapter two describes several types of packages and confrontation of their characteristics. Chapter three considers possibilities of corrections these boards bedded with packages, mounting and demounting of these packages, method of camera control and also inspection of the soldering process. Chapter four attend to practical measuring of thermal profiles and their optimalization.

This diplomas thesis deals with specific technologies and manufacture of BGA and QFN packages. Also summarizes the most used test methods for assessing the reliability for. Describes the making of equipment for soldering in a nitrogen atmosphere, followed by comparison solder joints of BGA and QFN forming in different atmosphere. Finally, summarizes knowledge about the process of soldering and desoldering lead-free solders for BGA packages, followed by experimental evaluation of the causes of malfunction of repaired samples.

The aim of this project is using the CAE system to analyze the distribution of the temperature profile brazing furnace DIMA 0180. To create the model is used SolidWorks Premium 2012. The simulation is performed using the Flow Simulation. This work builds on the knowledge diploma thesis by Martin Procházka titled The effect of different heat capacities and components on the longitudinal temperature profile for reflow soldering. We start from the knowledge of heat transfer, especially of heat conduction and radiation, which appear in the furnace.

This diploma thesis is focused on detecting of defects on BGA (Ball Grid Array) components using of X-ray. Defects are formed during reflow BGA components during assembly, but also later due to mechanical and thermal stress. Therefore, there is an overview of defects and methods of diagnosis of BGA packages eg .: modern X-ray defect detection or micro sections. There is disclosed a device NORDSON DAGE XD7600NT its operation and setup. The device enables advanced methods of scanning called X-plane. For creating 3D models used reconstructive software called CERA, which uses raw data from the method of X-Plane.