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The aim of this paper is to present non-destructive and destructive methods of failure analysis of epoxy moulded IC packages on the example of power MOSFETs in SOT-227 package.

A power MOSFET in SOT-227 package was examined twice using X-ray inspection, at first as the whole component to check if it is damaged and then after removing the upper part of package by mechanical grinding. The purpose of the second X-ray inspection was to prepare images for estimation of the total number and approximate location of voids in soft solder layers. Finally, power MOSFETs were subjected to decapsulation process using a concentrated sulphuric acid to verify existence of damage areas noticed during X-ray analysis and to observe other possible failures such as cracks in aluminium metallization or wires deformation.

X-ray analysis was revealed to be adequate technique to detect damage (e.g. meltings) in power MOSFETs in SOT-227 package, but only when tested components were analysed in the side view. This type of analysis combined with a graphic software is also suitable for voids estimation in soft solder layers. Moreover, it was found that a single acid (concentrated sulphuric acid) at elevated temperature can be successfully used for decapsulation of power MOSFETs in SOT-227 package without damage of aluminium metallization and aluminium wires. Such decapsulation process enables analysis of defects in wire, die and package materials.

Further investigations are required to examine if the presented methods of failures analysis can be used for other types of components (e.g. high power resistors) in similar packages.

The described methods of failure analysis can find application in electronic industry to select components which are free of damage and in effect which allow to produce high reliable devices. Apart from it, the presented method is applicable to evaluate reasons of improper work of tested electronic devices and to identify faked components.

This paper contains valuable information for research and technical staff involved in the assessment of electronic devices who needs practical methods of failure analysis of epoxy moulded IC packages.

In the previous two articles the emphasis was on wet and electrochemical techniques, with particular reference to the potentiostat. The physical examination of corrosion products is of equal importance, especially, for example, in the study of oxidation by dry gases at elevated temperatures where electrochemical studies are not normally feasible. In this article the application of physical techniques to corrosion studies will be discussed.

X‐ray laminographic image can provide more useful information about the internal state of electronic packaging than x‐ray radiographic image does. Many kinds of laminographic system have been developed for obtaining the cross‐sectional image. Proposes an axial laminographic system, which can be constructed by usual automatic radiographic system without any rotating x‐ray head and detector system. Explains that this method can be implemented to make the usual radiographic x‐ray inspection system equal to the power of a laminographic system.

Within Calderdale and Kirklees Health Authority area there are two distinct groups of general practitioners (GPs) ‐Huddersfield and Halifax. Following a small pilot study, a modified X‐ray request form was developed for sole use by the Huddersfield GPs. This X‐ray request form encouraged the local GPs to specify their reasons for referral. During the year in which the modified X‐ray request form was circulating within Huddersfield, the GP community was 0.66 times as likely (less likely) to request lumbar spine X‐rays in comparison with the community in Halifax. The 95% confidence intervals were 0.57–0.77, indicating that this is a highly‐significant result.

The use of X‐rays for inspecting baggage and weld quality is well known, however, recent food contamination scares have put the spotlight on new and ever more demanding applications.

The purpose of this paper is to describe a novel, nanomaterial‐based X‐ray imaging technology, developed at the University of North Carolina.

The paper describes a unique X‐ray source, based on field emission from a carbon nanotube (CNT) cold cathode and discusses its application to computer tomography (CT).

CNT‐based X‐ray sources are shown to offer improved performance over conventional thermionic devices and allow the design of gantry‐free, stationary CT systems with faster scanning speeds and better image quality. The field emission technology has been commercialised by Xintek and a joint venture with Siemens, XinRay Systems, aims to commercialise CT imagers based on the technology.

The paper describes a novel approach to the generation of X‐rays and its use in medical CT imaging systems.

Medical images are increasingly popular; therefore, the analysis of these images based on deep learning helps diagnose diseases become more and more essential and necessary. Recently, the shoulder implant X-ray image classification (SIXIC) dataset that includes X-ray images of implanted shoulder prostheses produced by four manufacturers was released. The implant's model detection helps to select the correct equipment and procedures in the upcoming surgery.

This study proposes a robust model named X-Net to improve the predictability for shoulder implants X-ray image classification in the SIXIC dataset. The X-Net model utilizes the Squeeze and Excitation (SE) block integrated into Residual Network (ResNet) module. The SE module aims to weigh each feature map extracted from ResNet, which aids in improving the performance. The feature extraction process of X-Net model is performed by both modules: ResNet and SE modules. The final feature is obtained by incorporating the extracted features from the above steps, which brings more important characteristics of X-ray images in the input dataset. Next, X-Net uses this fine-grained feature to classify the input images into four classes (Cofield, Depuy, Zimmer and Tornier) in the SIXIC dataset.

Experiments are conducted to show the proposed approach's effectiveness compared with other state-of-the-art methods for SIXIC. The experimental results indicate that the approach outperforms the various experimental methods in terms of several performance metrics. In addition, the proposed approach provides the new state of the art results in all performance metrics, such as accuracy, precision, recall, F1-score and area under the curve (AUC), for the experimental dataset.

The proposed method with high predictive performance can be used to assist in the treatment of injured shoulder joints.

The initial excitement over increased solder joint densities, higher manufacturing throughput, and superior electrical performance brought forth by surface mount technology (SMT) has been replaced by frustrations over lower yields and the inherent difficulties of inspecting hidden solder joints. In the plated through hole (PTH) process, rework and inspection tasks were not only relatively easier tasks, but also less costly. The high cost of inspecting and reworking SMT assemblies dictates a rethinking of the assembly process. Increasing first time yields becomes the key to reducing SMT inspection and rework costs. In a high volume facility, a 100% visual inspection process is not feasible because of the high cost of inspection and rework. However, if a company intends to remain competitive, inspection and rework must be reduced without a sacrifice to final product quality. Realising that it is not possible to ‘inspect’ quality into a product, improved yield must result from a controlled process environment. By maintaining a controlled environment, one will be provided with lower inspection costs, lower rework costs, lower scrap and, in the final analysis, improved product quality. At the heart of any process control environment should be a real‐time process control system designed specifically to accommodate SMT process defects. Process monitoring is accomplished by locating and identifying SMT process flaws. These flaws will then be reported to a host system for statistical analysis. These are statistical data used to make timely adjustments to the various stages of the assembly process in a real‐time manner. Being able to monitor the production process objectively in real time, and detect hidden flaws accurately, are the keys to having a successful process inspection system. Automated X‐ray Inspection is gaining acceptance as a viable process monitoring tool, capable of detecting and reporting SMT process flaws, including those hidden flaws not reported with typical visual inspection systems. The purpose of this paper is to show how an Automated X‐ray Inspection system can be integrated into the SMT production process as a cost‐effective method for improving SMT yield.

This paper presents an overview of the x‐ray guided robotic radiosurgery system that has been developed for the ablation of solid tumors. A robot‐mounted linear accelerator is directed through a sequence of positions and orientations designed to deliver high radiation dosages focused at a specific location. Patient movement during treatment is identified by stereo x‐ray measurements and the robotic system adjusts the linear accelerator prior to the delivery of radiation at each location. The result is accurate delivery without rigid fixation of the tumor relative to the treatment system.

To present an overview of the research and development carried out by an EC Framework 6 part funded consortium, known as MICROSCAN, for the implementation of an in‐line PCB inspection prototype system that is capable of offering comprehensive defect detection.

Four non‐destructive testing inspection modules based on digital radiography (X‐ray) inspection, thermal inspection, automated‐optical inspection and acoustic inspection have been integrated to form a combined inspection system.

A proof in principle in‐line PCB inspection system, utilising four different inspection techniques, has been developed and demonstrated. The system is based on a generic mechanical, electrical and software communications platform culminating in a flexible system that enables the inspection modules to be used separately, together or interchanged to give the best results in terms of inspection coverage and inspection throughput.

In its current embodiment, the prototype is suited to inspection of high‐return PCBs, particularly those used in medical and aerospace products, rather than high‐throughput PCB production work. The X‐ray inspection module is the slowest inspection technique and combining four different inspection techniques reduces the inspection throughput of the whole system to that of the X‐ray inspection module. Further, trials and investigations need to be carried out to improve inspection throughput.

The novelty of the system is that it is the first time that four inspection techniques have been combined to give the capability of 100 per cent defect coverage.