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Analysis of Defects on PCB Using X-RAY, 3D SW CERA and Micro-Sections
Vala, Martin
This paper deals with detecting of defects on BGA (Ball Grid Array) components using X-ray. Defects are formed throw reflow process of 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.
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XRD characterization of electrodes and electrode materials for electrochemical power sources
Klvač, Ondřej ; Chladil, Ladislav (referee) ; Čech, Ondřej (advisor)
The thesis describes available choices of methods for research of electrochemical power source electrode strcture by x-ray diffraction spectroscopy. At first there is a theoretical computation of difractogram. Then there are discussed possibilities of in-situ and ex-situ techniques as background research. Practical part of thesis compares theoretical assumptions to measurements of lithium and sodium cells, including analyze of crystallographic phases and lattice constants. As a conclusion, there are discussed possibilities of subsequent research.
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Precise setup of production process to minimalize presence of voids in solder joints where were used alloy SAC305
Slavík, Pavel ; Macho, Tomáš (referee) ; Valach, Soběslav (advisor)
The theoretical part of dissertation is devoted to familiarization with the process of assembly and soldering of PCBs. There are described the selected types of lead-free solder paste, the various procedures of flux deposition, where the greater part is focuses to the printing through template. Also, I analyze the different procedures shouldering and soldering. I focused mainly on the mechanical mounting of SMD components soldering with help convection reflow and soldering in the vapor. In the practical part is described the design of the test PCB, methodology of assembly PCB and soldering various technologies with predefined settings. The analysis of the results is done by a non-destructive x-ray method and destructive micro-cut method. The x-ray method detects the position and size of the voids in the solder. This information is used for faster processing of micro-cut. The micro-cut method is included in the analysis for a more detailed examination of the solder joint. At the end of the thesis, there is a summary of the recommendation that the setting of the manufacturing process increases the quality of the brazed joint.
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Design of Intelligent Network Module for 2D Radiation Data Acquisition
Lelek, Martin ; Polášková, Lenka (referee) ; Wilfert, Otakar (advisor)
This thesis describes about theoretical design and practical realization of self-contained module for intensity and absorbed dose measuring of X-Radiation from High Voltage X-RAY industrial sources. In the first part, thesis is focused on ways and solutions of radiation protection and principles of measuring absorbed dose and intensity of radiation and possibilities of sending measured data through sensor networks. In the second part, the complete schematic of measuring module is solved, critical blocks are tested and design of PCB is done. Detection circuit, blocks for optical and acoustic signaling, power management and control of the entire device are designed. Detection circuit uses a GM Tube. Next, main box of whole device is designed and made by 3D printing technology. The next step is putting hardware into operation and writing test firmware included verification of wireless communication through WiFi.
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Reliability of LED Panels Solder Joints
Šimon, Vojtěch ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
Thesis is focused on the effect of heating factor on quality of solder joints. In theoretical part is solved reflow soldering technology, problematice of solder paste choice or criteria of soldering profile setting. The practical part is dedicated to demonstrating the impact of heating factor on solder joint quality. There are used X-Ray analysis, microsections and electron microscopy. In the final part of this thesis are summarized knowledge from theoretical part and experimental obtained results to defend of next steps in diploma thesis.
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Bioinformatics Tool for Protein Structure Prediction
Plaga, Michal ; Burgetová, Ivana (referee) ; Martínek, Tomáš (advisor)
The goal of this thesis is test and comparation of the offline tools for prediction of protein structure and creation of metaprediktor, which allows the user to select the appropriate tool, according to given parameters. Testing tool is based on a dataset of proteins, which is based on the SCOP database and it is trying to be as balanced as possible to include proteins from different families and thus could best evaluate individual tools. The results of this thesis are requirements of metaprediktor and also which data and settings can be allowed and processed and how it will be implemented.
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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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REBALLING OF BGA PACKAGES USING PACE TF2700 EQUIPMENT
Roháček, Peter ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
The Diploma thesis is focused on reballing of BGA packages with the device PACE TF 2700. It describes the general types of BGA packages, their defects, importance of thermal management to the solder techniques, where it is also talked about the meaning of solders and fluxes for the joint. The work informs about the most common methods of reballing, the proper handling of components and the current situation with BGA stencils on the market. It briefly describes the device operation of PACE TF 2700, that is working on the convection and IR principle of heating components. It deals with the manufacturing of the template, dummy BGA packages, the test plates, creation of the thermo profile, comparing and examining the defects and their causes, which had the most significant impact on the results. The achievements would serve for comparing them with the results of the future laboratory exercises or as a subject for further works.
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Bone densitometry
ŠÍRKOVÁ, Eliška
According to the World Health Organization (WHO) osteoporosis is defined as: "Increasing of systemic disease of skeleton. The characteristic feature is the lack of bone substance and disorders of microarchitecture of bone tissue. The result of the disorder is disposition to fractures. Earlier the disease was not diagnosed until it got to the stage of occurrence of osteoporotic fracture. Nowadays it is anticipated by means of BMD. Especially women at the age of postmenopause and older men are invited for the medical check-up. However, younger people and even children are invited too. The main indications for the BMD measurement are women who stopped a hormonal curing by using estrogen or they are at the age of postmenopause. It is also recommended for patients with increased occurence of fractures caused by small force and for patients who had a big weight loss. Last, but not least, it is good for men in their seventies, patients who are considering the pharmacological treatment and of course patients with visible effects of the treatment. The densitometry medical check-up itself, known as DEXA, is painless and non-invasive method, using which we can find comprehensive information about the amount of bone mineral in examined section of bone. The parts, where the density is measured, are the parts that are the most abraded. These are vertebrae L1 L4, distal antebrachium, proximal femur, ribs and proximal humerus. It is necessary to check BMD patients with the same apparatus and software during the each medical check-up. For the checking measurement the patients comes every year. Nevertheless, not later than after the two years after the first medical check-up. The purpose of the thesis is research including two main points: analysis of the data acquired from densitometric station of 'Nemocnice České Budějovice a.s. and omparison of the data of patients with a regard to age, sex and the kind of disease. Based on the research it was found out, that division of the patients into groups according to the diagnosis is not conforming. 95% of patients are suffering from various stages of osteoporosis. Only 5% of patients have different diagnosis. Based on the data from the research it was found out that there are ten-times more women who undertook the medical check-up. It is clear, why mainly women undertake the osteoporosis medical check-up. The sudden change of metabolism of bones, mostly related to climacteric, the end of treatment using estrogen, or lactation, is difficult situation and it is very stressful for the whole organism.
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X-ray beam hardening effect simulation
Milek, Jakub ; Kolář, Radim (referee) ; Drastich, Aleš (advisor)
At the beginning of this work the physics related background and it’s interaction with matter is described, followed by explanation of filters influence on X-ray spectrum. Linear attenuation coefficient is described and so are other related physical quantities. In the end the description of a simulator is presented.
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