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Non‐planarity of assemblies and co‐planarity variation effects on anisotropic conductive adhesive (ACA) assemblies have been a concern for ACA users since the materials are first devised. The primary objective of this paper is to introduce a new experimental method for studying co‐planarity variation effects on ACA assemblies.

The approach simulates non‐planarity through deliberate chip rotation during the ACA bonding process, thereby locking different levels of co‐planarity variation into ACA test assemblies. Scanning electron microscope (SEM) analysis and electrical joint resistance measurement using the four wire resistance (FWR) method are used to mechanically and electrically examine the connection quality of the ACA assemblies bonded with non‐planar joints, for which the chip and substrate patterns are specially designed to allow joint resistance measurement using the FWR method.

Typical experiments and their results are presented and analysed. The bond thickness differences between the SEM measurements and calculations indicate that the real rotations are smaller than those predicted by the calculations. The typical experimental results show that the joint resistance reduces as the deformation increases until reaching a relatively stable value after a certain deformation degree.

The average joint resistances in the rotated samples are all bigger than those measured in the un‐rotated samples. This raises the question as to whether the joint resistances of ACA assemblies are more significantly affected by other affects of non‐planarity than just by its effect on bond thickness. However, before this can be confirmed, more research must be done to check if this behaviour happens for different bonding forces.

This paper reports a novel and simple experiment that can be used to examine the effects of co‐planarity variation on the electrical performance of ACA assemblies, by creating different bond thicknesses that are normally difficult to achieve by changing the bonding pressure, since ACA bond thicknesses are not linearly related to the bonding force. The merit of the technique is that there is no need to manufacture chip bumps and substrate pads with different geometries, or to control the bond pressure, to achieve bond thickness variation in ACA assemblies.

A new microcomputer‐controlled wire bond pull tester, designed to enable manufacturers of hybrid microcircuits to perform fully automatic non‐destructive pull testing of wire connections, has been introduced by Hughes Aircraft Company's industrial products division.

From 14–16 May 1985, the Scottish Electronics Production Show will open its doors to Scotland's electronics manufacturers. Design and production engineers, together with purchasing management, will be able to compare and select the latest equipment and materials available from over a hundred companies.

The purpose of this paper is to discuss the fabrication technology and test of thermo-pneumatic actuator utilizing Si₃N₄-polyimide thin film membrane. Thin film polyimide membrane capped with Si₃N₄ thin layer is used as actuator membrane which is able to deform through thermal forces inside an isolated chamber. The fabricated membrane will be suitable for thermo-pneumatic-based membrane actuation for lab-on-chip application.

The actuator device consisting of a micro-heater, a Si-based micro-chamber and a heat-sensitive square-shaped membrane is fabricated using surface and bulk-micromachining process, with an additional adhesive bonding process. The polyimide membrane is capped with a thin silicon nitride layer that is fabricated by using etch stop technique and spin coating.

The deformation property of the membrane depend on the volumetric expansion of air particles in the heat chamber as a result of temperature increase generated from the micro-heater inside the chamber. Preliminary testing showed that the fabricated micro-heater has the capability to generate heat in the chamber with a temperature increase of 18.8 °C/min. Analysis on membrane deflection against temperature increase showed that heat-sensitive thin polyimide membrane can perform the deflection up to 65 μm for a temperature increase of 57°C.

The dual layer polyimide capped with Si₃N₄ was used as the membrane material. The nitride layer allowed the polyimide membrane for working at extreme heat condition. The process technique is simple implementing standard micro-electro-mechanical systems process.

The purpose of this paper is to share valuable information about metallization in microelectronic industries by implementing tungsten silicide (WSi) thin film materials.

Direct current plasma magnetron sputtering technique was employed for the WSi film growth. Different sputtering parameters were investigated, and the WSi films were characterized using four‐point probe electrical measurement method.

The experimental results reveal that the sputtering parameters such as deposition pressure and substrate temperature exert significant influence on the electrical properties of the WSi films.

By tuning the sputtering parameters, the electrical properties of the WSi films can be optimized and the film resistivity can be reduced significantly.

The investigation results presented in this paper are useful information for microelectronic industries in the area of microelectronic devices metallization.

The fabrication method described in this paper allows fabricating low‐resistivity WSi films by employing a lower deposition pressure and a lower substrate temperature.

Dates: 29–31 May 1991 Venue: De Doelen Conference Centre, Rotterdam, The Netherlands The Benelux Chapter of the International Society for Hybrid Microelectronics will be organising the 8th European Microelectronics Conference. The event will take place at ‘De Doelen’, Rotterdam, The Netherlands, from 29 to 31 May 1991.

ISHM‐Benelux held its 1987 Autumn Conference on 29 October, at the Antwerp Crest Hotel. This one‐day meeting focused on applications of hybrid circuit technology in various fields of electronic and related industries.