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After a brief introduction to the advantages and method of construction of flip chip solder bond devices, this paper looks at different techniques that can be used to inspect these devices at various stages in their construction. These techniques include optical, infra‐red, acoustic and electron microscopy, radiograph, electrical and tensile testing. The advantages and limitations of each of the techniques are discussed and an outline inspection schedule is suggested.

A measurement tool, capable of monitoring misalignment of layers in multilayer printed circuit boards, is described. Its uses, limitations and its advantages for use in SPC and reliability predictions are highlighted.

This paper examines beliefs and attitudes in the context of how they influence the decisions of university Human Research Ethics Committees (HRECs) as a preface to undertaking an empirical study in this area. It also aims at establishing a conceptual framework to guide the design of a questionnaire targeting beliefs about research ethics and the implications of these beliefs on review practices of HREC members throughout Australia.

Using content analysis of the extant body of the literature the paper examines the relationship between the concepts of beliefs and knowledge, beliefs and attitudes, and among beliefs, attitudes and behaviour in the context of research ethics.

The discussion suggests that ethics approval practices can, at times, be influenced more by personal beliefs than by contemporary review standards. It is also suggested that personal beliefs can be transmitted through the review process and that HRECs can serve to influence the transfer of values from reviewers to researchers.

The framework that this paper presents has the potential to appraise an array of perspectives which in turn would guide the design of professional development programs. In addition, an improved, more nuanced understanding of how HREC members make ethical decisions will positively impact and inform best practice in the review of ethical applications for research projects.

The paper presents a novel theoretical framework underpinning research ethics reviewer beliefs and attitudes within a contemporary context.

This paper looks at the implications of increases in system speed and density for the interconnection system, noting particularly the increased requirements placed on the substrate and tracking system. It reviews the properties required of substrates and the limitations derived from the materials used and the processes needed to put tracks on them. Those areas where these requirements are in conflict are highlighted, including such low technology problems as the limited size availability of substrate prepregs which may limit the tracking density achievable on the newer, more advanced low dielectric materials. Some limitations and trade‐offs are identified.

The problem of providing a reliable and cost‐effective interconnection system between semiconductor devices and other add‐on components and the film circuit has been central to the development of hybrid microelectronic technology since its inception. Many of the techniques used have been adopted from those developed primarily for the semiconductor industry, and not all of these have been entirely suited to hybrid microcircuit production. Thermocompression bonding using gold wire, for example, while acceptable as a process for lead attachment to discrete transistors or semiconductor integrated circuits, in which the duration of exposure to raised temperature is quite short, may be the cause of early or delayed failure when applied to the assembly of a hybrid of any complexity, when the time at temperature is necessarily much longer.

This study describes a peel test to quantitatively measure the adhesion of dry film photoresist on copper. Using this peeling method, the adhesion effects of: (a) the copper surface treatments, (b) the UV radiation of a laminated resist, and (c) the baking of a resist laminated coupon were measured. Adhesive tape with rectangular or wedge‐shaped openings was placed between the photoresist and copper surfaces with the adhesive side facing the resist. The openings in the tape allowed for contact between the copper surface and the resist, and the opening dimensions determined the width and length of contact. With the aid of the adhesive tape, a better grip of the resist was obtained during the peeling. The results of this study led to the following conclusions: A tin‐silane (SNS) treated copper surface with a peeling strength of 4–7 lbs/in. was the most effective surface treatment. A UV radiation dose below or equal to 32 mJ/cm2 produces an adhesion of the resist with micro‐etched copper of 38±03 lbs/in; above this dose, adhesion increases. Thermal baking improves adhesion; the calculated activation energy of a micro‐etched copper surface with the resist is 65 kcal/mole.

The annual Autumn Conference of the British Association for Brazing and Soldering offers a forum for discussions between scientists and engineers involved with two technologies which, because of their obvious similarities, would be expected to be of mutual benefit and learning. In reality both the science and the practice of brazing and soldering are quite different. I suspect, with some regret, the BABS Management Committee decided that for the first time this division be formally recognised by offering soldering as the subject of the first day and brazing and diffusion bonding the subjects of the second. This report covers the soldering day only, during which seven papers were presented:

The purpose of this paper is to identify the major parameters which affect the chances of contamination occurring, and then to evaluate conventional cleaning techniques with respect to these factors. The paper will next describe a new approach to contamination control which minimises the risk of contamination in a cost‐effective manner. In conclusion, some aspects of the circuit board manufacturing process which are particularly sensitive to contamination and which may benefit from the application of ‘Just in Time’ cleaning are described.

A silver‐palladium thick film conductor for aluminum nitride (AlN) substrate has been developed. This conductor film on AlN ceramics had low sheet resistivity, high adhesion strength and good wettability with Pb‐Sn solder. The frit powder of lead borosilicate glass was used as inorganic binders to enhance the adhesion between the conductor and ceramics. After sintering the conductor film connected with the AlN substrate through frit bonding, no transition phases but a multilayer structure is present in the interface. The softening point of the glass was important to the adhesion strength of conductor film. In order to achieve good adhesion, it is necessary that the glass has a proper softening point (about 500‐650°C).