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Fabrication and performance characteristics of a thick‐film laser power detector are presented. The new sensor combines the advantages of a circular resistor and highly sensitive NTC resistor paste. As a consequence of the layout, the sensitivity of this sensor depends slightly on the eccentricity and positioning of the laser beam. Therefore the measurement is simpler and the linearity and the reliability of detector are of a high standard.

Fast laser soldering processes are very attractive for the production of miniaturized interconnections with high reliability as they allow solder joint quality assurance during soldering. In order to evaluate the solder joint quality temporal changes of the temperature distribution inside the solder joint due to melting of the solder and wetting of the component and the pad metallizations must be well understood. In this paper we present thermal simulations of fast laser soldering processes taking the essential changes of the solder geometry into account. Moreover, we use a new relation for the calculation of the moment of wetting in dependence of the interface temperature. With this model the influence of the wettability of the pad and the component metallization and of the position of the laser beam on the temperature distribution inside the solder joint are investigated.

This paper aims to perform thermal and mechanical characterization for silver-based sintered thermal joints. Layer quality affects thermal and mechanical performance, and it is important to achieve information about how materials and process parameters influence them.

Thermal investigation of the thermal joints analysis method was focused on determination of thermal resistance, where temperature measurements were performed using infrared camera. They were performed in two modes: steady-state analysis and dynamic analysis. Mechanical analysis based on measurements of mechanical shear force. Additional characterizations based on X-ray image analysis (image thresholding), optical microscope of polished cross-section and scanning electron microscope image analysis were proposed.

Sample surface modification affects thermal resistance. Silver metallization exhibits the lowest thermal resistance and the highest mechanical strength compared to the pure Si surface. The type of dynamic analysis affects the results of the thermal resistance.

Investigation of the layer quality influence on mechanical and thermal performance provided information about different joint types.

George MacMahon has been appointed Product Manager for Thick Film Materials by W. C. Heraeus, Hanau, Germany, to further increase the company's business throughout Europe and beyond. He will help to co‐ordinate technical support for the general sales effort, including the presentation of technical information at meetings and exhibitions.

To design a flexible integrated robotic assembly and rework (remanufacturing) cell for assembly, selective assembly and rework of advanced surface mount components (SMCs) using the generic methodology developed in this paper.

Manual rework procedures are investigated for all advanced SMCs. General and specific component‐related rework considerations are obtained and necessary tooling candidates for automation are determined. This is followed by determination of the specific automated rework procedure and selection of suitable tooling for automated robotic rework and generation and evaluation of design concepts.

The developed methodology, which considers the reflow tool at the centre of the development process, has worked well in designing a flexible integrated robotic assembly and rework cell.

This study identified the rework requirements for advanced SMCs, the essential features for rework reflow tools, criteria for comparing reflow tools, and a generic procedure for design and concept selection.

It provides valuable knowledge for designers of flexible integrated robotic assembly and rework cells for assembly, selective assembly and rework of advanced SMCs.

The purpose of this paper is to apply the developed systematic mechanical design methodologies, that are obtained in part I, to investigate their success in designing mechanics of a flexible printed circuit board assembly (PCBA) rework cell.

The decision of soldering and desoldering tool, which is the most critical function of a PCBA rework or remanufacturing cell, significantly influences overall design concept. Therefore, the paper starts by applying the design methodology to the soldering and desoldering function. The same study is repeated for the rest of the sub‐functions but only the results are provided.

An application of rework machine design methodology for the design of a PCBA rework cell has been made available. In addition to this, the embedded knowledge, such as the requirements list, the function structure, the function/means tree, the weighted objective tree and evaluation chart for the soldering and desoldering function are provided.

The paper is the first work providing both embedded knowledge and the application of the systematic design methodology for the design of a fully automated flexible PCBA rework cell. The methodology leads rework machine designers in a well‐controlled and structured design environment.

The design methodology can be applied to all functions or targeted on key weighted areas to ensure that the designed rework machine meets the key areas of concerns. Furthermore, the methodology is generic and may be used to develop other complex manufacturing sytems.

Morton International Inc. have purchased Hoechst AG's printed circuit materials business including their Ozatec dry film and liquid primary imaging photoresists, Ozatec liquid photoimageable solder masks and related process equipment. Concurrently, Hoechst and its US subsidiary Hoechst Celanese Corporation purchased Morton's semiconductor photoresist business. Completion of these transactions was effective from 4 August 1993.

ISHM‐Benelux has recently set up a permanent secretariat at the following address:

The purpose of this paper is to investigate the thermal behaviour of thin- and thick-film resistor with different dimensions and contacts embedded into printed circuit board (PCB) and compare them to the similar constructions of discrete chip resistors assembled to standard PCBs.

In investigations the thin- and thick-film embedded resistors with the bar form in different dimensions and configurations of contacts as well as rectangular chip resistors in package 0603 and 0402 were used. In tests were carried out the measurements of dissipated power in temperature of resistor about 40°C, 70°C and 155°C. The power dissipation was calculated as a multiplying of electrical current flowing through the resistor with voltage across the resistor. The dissipation of heat generated by electrical current flowing through resistors was examined by means of the FLIR A320 thermographic camera with lens Closeup×2 and the power source.

The results show that, in case of chip resistors, the intensity of heat radiation strongly depends on dimensions of copper contact lands and also depends on the dimensions of the resistor. In case of embedded resistors, with comparable dimensions to chip resistors, they have lower ability to power dissipation, as well as the copper contact lands dimensions have lower influence. The thermal radiation through resin material is not as effective as it is in case of resistors assembled on PCB. However, the embedded thick-film resistors, especially made of paste Minico M2010, have already the similar parameters to 0402 chip resistors.

Research shows that embedded resistors can be used interchangeably with SMD resistors it allows to open up space on the surface of PCB, but it should be taken into account the lower energy dissipation capabilities. It is suggested that further studies are necessary for accurately determining the thermal effects and investigate the structures of embedded passive components that allow for better heat management.

Thermal stability of embedded resistors during operation is a critical factor of success of embedded resistor technology. The way of power dissipation and heat resistance are one of the important operating parameters of these components. The results provide information about the power and the energy dissipation of embedded thin- and thick-film resistors compared to the standard surface mount technology.

Accurate alignment is vital to acquire high‐quality joints with less negative effects on the rest parts of the chip or other components on a board. The purpose of this paper is to develop an integrated laser soldering system, which is accurate, compact, and flexible.

The system combines an X‐Y stage, a computer vision module and a laser module. It would automatically sense the soldering pads with computer vision, fulfill the alignment of laser beam and soldering pads together with the motion system, and finish the soldering work with laser power.

Based on the analysis of experimental data, it is found that lens distortion and assembly angular errors of the X‐Y stage play a distinct role on the alignment errors.

The paper proposes an algorithm based on straight line method to reduce image distortion, and a compensation algorithm on the angular errors of the X‐Y positioning stage. Experimental results show that the overall precision is satisfied for fine pitch applications and the system performs well.