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A flip chip on board technology fully compatible with current PCB facilities is reported. It used reflow soldering for chip attachment. It required electroless nickel/immersion gold finishing on the board pads as well as on the chip pads. A no‐clean solder paste was printed on the boards before chip placement. Thus, there was no requirement for solder deposition on the chip side. Assembly tests with various chip formats proved the feasibility of this technology. X‐ray inspection and cross‐sectioning revealed the good shape and alignment of the reflowed solder joints. The reliability of underfilled assemblies was studied by ‐40 to 125°C thermal cycling. This approach is especially suitable for prototype or low volume productions as it eliminates the solder bumping process on the chip side, which is usually performed on the wafer level.

This year's Internepcon Production Exhibition and Conference (22–24 March 1988, National Exhibition Centre, Birmingham) promises to be the biggest ever in the event's twenty‐one year history and will host a number of special new features.