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Thermal aging of lead-free low-temperature joints
Jansa, Vojtěch ; Šandera, Josef (referee) ; Adámek, Martin (advisor)
The aim of this masterś thesis is to investigate properties of lead-free low-temperature solders after termal aging. The theoretical part is focused on various types of lead - free solders, pastes used for the manufacture of electrical circuits by thick-film technology and methods of testing the properties of the soldered joints. The practical part deals with the design and production of test substrates for testing the solder joints formed between the SMD component and the ceramic substrate. Two solder bismuth-containing solder was selected for testing, the SAC solder was selected as the reference. After aging with temperature cycling from -30 ° C to 115 ° C, the data obtained by testing the mechanical strength of the solder joint by the shear test is evaluated.
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Lead-Free solder thermal and microstructure analysis
Klepárníková, Eliška ; Molliková, Eva (referee) ; Jan, Vít (advisor)
The bachelor thesis deals with Ag-Sn-Sb system, construction of pseudobinary diagram 90An10Sb – 90Sn10Sb and construction of ternary diagram at 20 C. The theoretical part deals with soldering, phase diagrams and methodics of determination of phase diagrams. The experimental part is focused on describing the creation of five alloys and their further exploration. Alloy analyzes were performed by differential scanning calorimetry (DSC), light microscope and scanning electron microscope. Results from these thermal and microstructural analyzes were processed into the resulting pseudobinary and ternary diagram.
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The comparison of properties of solder joints on ceramic substrates by shear tests
Lipavský, Lubomír ; Schnederle, Petr (referee) ; Adámek, Martin (advisor)
This thesis deals with issues lead – free soldering in a protective atmosphere with a focus on mechanical tests. The theoretical part is focused on the types of lead-free solders, mechanical tests carried on the solder joints and various methods reflow soldering. It is also discussed reliability and durability of solder joints. Aim of the practical part is to compare the strength of solder joints using shear tests for various sizes of components, various concentrations of protective nitrogen atmosphere and various types of solder pastes. Testing is performed on a ceramic substrate, which differs from the works being carried on an organic substrate. For each type of solder paste is further processed by the percentage occurrences of each type tearing of solder joint.
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Optimalization of repair process in Surface Mount Technology
Vala, Radek ; Řezníček, Michal (referee) ; Szendiuch, Ivan (advisor)
This project deals with utilizing of IR 400 equipment for assembly and repair of SMD components soldered by lead-free solder materials. The part of the work concerns with optimizing of the temperature profile, which is very important in the repair to eliminate the damage of components and PCB. There was added controller R 500 and cooling equipment to allow better control of the temperature during the soldering cycle.
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Optimalization of soldering process on IR-400
Otáhal, Alexandr ; Nicák, Michal (referee) ; Szendiuch, Ivan (advisor)
This project deals with innovation of IR-400 equipment which is based on design and installation of temperature regulation, in both top and bottom side. This innovation enables adjustment of reflow temperature profile for repair and rework of SMD components by lead-free solder materials for both, FR4 and alumina substrates, as assembly of some special packages.
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Wetting of lead-free solders on ceramic substrates
Lipavský, Lubomír ; Otáhal, Alexandr (referee) ; Adámek, Martin (advisor)
This master's thesis deals with issue of lead-free soldering in protective atmosphere with focus on wetting test. Theorethical part is focused on the types of lead-free solders, wettability tests performed on solder joints, different types of soldering or comparison of influence of the base material in regards to the wetting of the solder. The goal of practical part is testing and comparison of spreadability of selected lead-free solder on two conductive surfaces with different concentration of oxygen in protective nitrogen atmosphere. Testing has been performed on ceramic substrate which differs this method from others, performed on organic substrate. For an over-melted solder, the crystal-growth on surface in regards to protective atmosphere concentration is shown.
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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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Testing of Solders in Protection Atmosphere
Vala, Radek ; Jankovský, Jaroslav (referee) ; Szendiuch, Ivan (advisor)
The project deals with the overall design and construction of equipment called the desiccators for brazing in a protective atmosphere. The device was designed and manufactured cooling and heating element. For the soldering various temperature profiles have been defined and adjusted, as for SnPb as well for lead-free solders. There was a realization of samples were measured and analyzed. Finally were realized micro sections for lead free solder.
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Research of the Quality of Solder Joints by BGA and QFN Packages
Otáhal, Alexandr ; Adámek, Martin (referee) ; Szendiuch, Ivan (advisor)
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.
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Research of the reliability of lead-free solder joints
Pelc, Miroslav ; Švecová, Olga (referee) ; Szendiuch, Ivan (advisor)
This work deals research of the reliability of leed-free solder joints. It summarizes the basic knowledge of lead-free solder alloys, soldering and testing process, the soldered joints. The work is done selecting the most important factors entering into the soldering process. The method of the DOE sought the optimal combination of factors, which would correspond to the highest quality solder joints.
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