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Solder Joint Electric Conductivity and Solder Joint Reliability
Lačný, Radek ; Stejskal, Petr (referee) ; Starý, Jiří (advisor)
This work is considered about changes of electric conductivity in lead-free soldered joint's affected by current and thermal stress. The theoretical part describes factors influencing the solder joint electric conductivity and solder joint reliability. The basis of the practical part is the design of the testing method of the soldered joint's electric conductivity. The aim of this part is to measure and observe changes of solder joint electric conductivity after current and thermal stress in various material a procedural combinations.
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Solder Joint Reliability Prediction
Stejskal, Petr ; Skočil, Vlastimil (referee) ; Hovorka, Ladislav (referee) ; Kazelle, Jiří (advisor)
The thesis deals issue of the solder joint reliability and diagnostics. The manufacturing technology of electronics currently features a very high level of perfection. A large number of electrical devices ends its functional life due to solder joint failure. The objective of presented research consists studies of processes taking place in the solder joint due to soldering and after soldering. To this end, I will employ several methods of diagnostics. Noise based methods of solder joint measurement was evaluated. Based on a detailed study and understanding of processes it can be solder joint reliability predicted.
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Definition of thermotension by lead and lead-free solders
Dvořák, Jaroslav ; Řezníček, Michal (referee) ; Jankovský, Jaroslav (advisor)
This research work is dealing with impact and size of the thermoelectric that may influence DC circuits. Main part of this thesis is to build experimental equipment for measurement of the thermoelectric and following usage this equipment for detection of the size the thermoelectric voltage for lead and lead-free solders. The theoretical part of this work deals with creation and usage of the thermoelectric in electrical engineering industry. In this particular part of this work is an example how the thermoelectric influence DC circuits. Then I describe thermoelectric generation from the motherboard to the die. The practical part of this thesis is focused on the development of the equipment for measuring of the thermoelectric of different types of materials. The Thermoelectric has been measured on two types of the lead, six types lead-free solders and on four types of the thermocouple wires. It has been measured within the range from 0°C to 80°C. In the end of this work is summary, where is reviewed witch of solders is the best for an applications affected by the thermoelectric.
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The possibilities of SMD components soldering by equipment Fritsch
Juračka, Martin ; Šandera, Josef (referee) ; Adámek, Martin (advisor)
This thesis focuses on soldering technology in microelectronics. It describes in detail the basic ways of soldering and repairs in electronics. This piece of work shows the principles of technological equipment for bulk soldering and used repairing devices. In the theoretical part of this work there are also briefly described the packages for integrated circuits that were used in the practical part of the thesis. The practical part of the thesis deals with setting of the heat profiles for hot air repair station Fritsch Mikroplacer for LQFP64, SOIC16, TSSOP14, QFN16 and DSBGA5 packages. The heat profiles for assembly and disassembly of the particular types of the packages on designed and manufactured test printed circuit board were set and tested. The resulting heat profiles are compared with the recommended heat profile of an ordinary solder paste SnAg3Cu0,5 which was used for the test. This thesis can serve as an aid for the further settings of heat profiles in other types of packages not only on Fritsch Mikroplacer devices, but also on other repairing devices of this type.
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Creep-fatigue models for solder joints reliability prediction
Novotný, Václav ; Šandera, Josef (referee) ; Švecová, Olga (advisor)
This project is focused on utilization of creep-fatigue models for estimate of reliability lead-free solder joints. It describes basic groups of creep-fatigue models, their usage for estimate of reliability solder joint, advantages and disadvantages. There are discusssed properties of single models, which are on different base. Purpose of this project is find optimal creep-fatigue model for lead-free solder and devise a test structure to which the model will be verified. Results are compared with theoretical calculations.
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Machanical testing of solder joints
Drab, Tomáš ; Šandera, Josef (referee) ; Szendiuch, Ivan (advisor)
The project contains theoretical research of electrotechnical manufacture for lead-free reflow soldering. It contains characterization of soldering processes. Includes variations of solder paste printing, principles of part placing and also reflow soldering process. The project appoints possibilities of testing solder joints strength, mainly focused on mechanical vibrations. It describes a design and preparation of solder joint strength test methods by mechanical vibrations. It compares influence of vibrations on part types and solder alloys.
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X-ray Defectoscopy
Velím, Michael ; Ondřej, Šimeček (referee) ; Starý, Jiří (advisor)
This diploma thesis deals with a defect detection with X-rays in the manufacturing procedure in the electrotechnical field. The work summarises the knowledge about technical possibilities of an X-ray device Cougar of YXlon company. Part of the work is focusing on scanning in 2D, 3D visualization and automatic analysis. The thesis describes inspection methods of a connector connection, the quality of a soldered joint and an encapsulated product.
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Analysis of Defects on PCB Using Modern Optical Method
Vala, Martin ; Řezníček, Michal (referee) ; Řihák, Pavel (advisor)
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.
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Lead Free Solder Joint Quality based on Heating Factor
Dosedla, Milan ; Zdeněk, Jurčík (referee) ; Starý, Jiří (advisor)
This bachelor’s thesis deals with influence of the heating factor on the quality of lead free solder joints in the reflow soldering process. It summarizes the basic knowledge and some requirements for soldered joints, analyses reflow profiles and presents some of the results published in the literature. Aim of the practical part is by samples soldered with different size of the heating factor determine and evaluate the impact of this factor to the strength and appearance of the final solder joint and the structure and thickness of the intermetallic layers.
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