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Plasma chemistry is employed almost exclusively for etching, cleaning and deposition processes in semiconductor device fabrication technology. As a natural expansion of this successful technique, attention has been directed at similar processes for thick film ceramic, thin film hybrid and more generally printed circuit board electronic assemblies. This paper discusses a variety of applications, some established and some experimental, where plasma is offering the benefits which semiconductor engineers have enjoyed for many years. Such applications include general organic removal, i.e., flux residues, finger print contamination and the removal/reduction of oxides and glass on thick film conductors to promote improvements in solderability and wire bondability.

Following the discussion at our recent Annual General Meeting, a questionnaire was sent out to all members. Almost half of them replied despite the fact that the time allowed for returning the questionnaire had been kept very short. Some members even provided detailed comments.

The paper briefly reviews the problems associated with resin smear in the manufacture of multilayer boards, the various types of material involved, and their influence on smear, and some of the techniques available for assessing the degree of smear. Following a short discussion on current methods of removing smear, the paper goes on to provide a critical comparison of traditional ‘wet’ chemical processes with the newer ‘dry’ plasma techniques. Key advantages of plasma desmearing are highlighted and the paper concludes with a more detailed description of the I V Products approach and current systems, together with results of recent development work.

Advanced Monolithic Systems, the Californian based precision voltage reference diode and OP‐amp manufacturer, has given specialist surface mount distributor Flint Distribution a franchise.

EMCA‐REMEX Products Ablestik Laboratories European Operations, Linton, Cambridge, have been awarded ISO 9002 accreditation for their quality system. The award represents 18 months of effort by the company, reviewing and tightening up procedures to reach the required standard. Most of the procedures were already in place but had not been documented to meet ISO standards. Raising employee quality awareness and the introduction of an internal quality audit schedule were a vital part of the exercise.

‘The Joining Environment’ Dates: 14–15 October 1992 Venue: Forte Posthouse, Coventry, England This Conference will provide a venue for discussion on advances in joining technology, and papers will cover a wide range of scientific and technical developments, focusing in particular on soldering, brazing and diffusion bonding practices which may involve environmental considerations.

The bonding of surface mounted components to printed wiring boards (PWBs) is critical to the high yield assembly of components to the PWB. This process is one of the last steps performed in a complicated manufacturing and assembly sequence. Poor bondability at this late stage of assembly produces costly scrap. Aggressive wet‐chemical processes may succeed in cleaning the residues from the metal bonding lands, but in the process the polymeric materials that surround the land areas may be mechanically or visually damaged. Even when processing is carefully controlled during the final formation of land areas in the conformal coating, a thin residue, often invisible to the eye, can partially or fully cover the bonding land area. The residue may be extremely thin, but it inhibits bonding and is very resistant to conventional wet‐chemical cleaning methods. Plasma chemical etching is the one chemical process which can remove the residue from the metal lands and restore bondability without damaging other surfaces of the ready‐to‐assemble PWB. This paper reports examples of plasma removed residues from PWB surface mount bonding lands. The land areas are defined in photodefinable conformal coatings by conventional photolithographic techniques and have a non‐visible surface residue which inhibits the subsequent plating or soldering of the copper land. Auger analyses of the copper land surfaces prior to plasma processing show significant carbon peaks indicative of a polymeric residue. Auger analyses of the copper land surfaces following plasma processing show that the strong carbon peaks are gone.

Using the very latest Visiongauge equipment, Excellon UK has launched a 24‐hour turnaround service to provide extremely accurate verification of drilled PCBs for process certification or machine calibration. The service allows customers to ensure optimum drill performance and to keep approval records without the time and cost of OPIC or CMM.

Attention was called in the March number of this Journal to the promotion of a Bill for the reconstitution of the Local Government Board, and the opinion was expressed that the renovated Department should contain among its staff “experts of the first rank in all the branches of science from which the knowledge essential for efficient administration can be drawn.”

PART VI Practical chemistry textbooks and miscellaneous books. Thirty‐nine practical chemistry textbooks were received from publishers for this part of the review and they have been briefly analyzed under the headings Physical, Inorganic, Organic, Quantitative analysis, and Other features, in Tables 1–4. It has not been possible to examine these in the same detail as the theory books previously considered. A number of other books which are used at ‘A/S’ level were also received and these have been tabulated: problem and calculation books in Table 5, and others in Table 6.