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Because they offer many properties favourable for IC package construction, ceramics have been in widespread use as an electronic package material since the early 1960s. In recent years, with trends towards higher speed semiconductors generating up to 30‐40 watts power, packaging materials must possess excellent thermal, electrical and mechanical properties. Aluminium nitride, with a thermal conductivity of 170 W/m.K., high fracture strength and a thermal coefficient of expansion match with silicon, has been used to manufacture multilayer LGA (land grid array) packages for high performance applications. A 725 AIN LGA has been manufactured and its performance characteristics have been compared with those of an alumina (with copper/tungsten slug) packaging alternative. Because of the high thermal conductivity of aluminium nitride, all designs can be made in a cavity‐up configuration, resulting in significant package body size reduction. The area under the cavity can be used for increasing I/O number and a ground plane can be inserted under the cavity, reducing simultaneous switching noise. Aluminium nitride is particularly beneficial for flip‐chip interconnection. Its close TCE match to silicon eliminates the stress reduction requirement for die underfill.

This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics include: theory – domain decomposition/partitioning, load balancing, parallel solvers/algorithms, parallel mesh generation, adaptive methods, and visualization/graphics; applications – structural mechanics problems, dynamic problems, material/geometrical non‐linear problems, contact problems, fracture mechanics, field problems, coupled problems, sensitivity and optimization, and other problems; hardware and software environments – hardware environments, programming techniques, and software development and presentations. The bibliography at the end of this paper contains 850 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1996 and 2002.

Aluminium nitride (AlN) is currently under investigation as a substrate material for use in microcircuit applications in particular where high thermal conductivity is required. Three commercially available substrate materials have been characterised using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The differences in thermal conductivity between the materials and also the difference from the theoretical thermal conductivity have been correlated to the presence of low thermal conductivity second phase regions between grains, defects within the crystal structure, the presence of oxygen impurities and poor sintering behaviour. The highest thermal conductivity substrate obtainable during this study was 140 W7m K. The substrates were identified as comprising hexagonal AIM having a wurtzite type structure. In addition, oxide and oxynitride phases were detected. The surface morphology of the substrates was also investigated, as it is the nature of the surface that will be of importance in determining the adhesion of applied films.

To become competitive with the industrialized world, a country may follow the following strategy: (1) stabilization of the exchange rate and the economy (extension of the state control of industries for a short period may be the next best alternative to a functioning free economy). A private market could then be phased in. (2) The privatization should be started from bottom up, e.g., start with selling small parts of various industries to develop a cadre of entrepreneurs and then sell bigger units or the whole firm. (3) Agencies should be developed to help/direct the transfer of technology from abroad.

The similarity of its temperature expansion coefficient to that of silicon, as well as its high thermal conductivity, makes AlN a material suited for application in microelectronics. A comparison of the various AlN manufacturers shows above all differences in the choice of sintering aids and the type of sintering process. A comparison of a standard paste system (Du Pont) with a new special development (Shoei) demonstrates the need for adapting the pastes to AlN ceramics. Thin film technology is possible at a standard similar to that of Al2O3.

A review of state‐of‐the‐art technology pertinent to tape automated bonding (for fine pitch, high I/O, high performance, high yield, high volume and high reliability) is presented. Emphasis is placed on a new understanding of the key elements (for example, tapes, bumps, inner lead bonding, testing and burn‐in on tape‐with‐chip, encapsulation, outer lead bonding, thermal management, reliability and rework) of this rapidly moving technology.

The reliability of 0·5 mm pitch, 208‐pin FQFP solder joints has been studied by experimental temperature cycling and 3‐D nonlinear finite element analysis. Temperature cycling results have been presented as a Weibull distribution. Thermal fatigue life of the solder joints has been estimated based on the calculated plastic strain and isothermal fatigue data on solders. A correlation between the experimental and analytical results has also been made.

Through the use of silicon‐on‐silicon packaging, VLSI chips can be interconnected by dense contacts and very fine conductor lines. Electrical and thermal properties obtained by means of this technique are discussed. The fabrication of small cooling channels in the silicon substrate and the application of the anodic bonding technique for chip mounting are demonstrated.

This paper presents an application of the physics‐of‐failure design philosophy to flip‐chip bonds in a microelectronic package. The physics‐of‐failure philosophy utilises knowledge of the life‐cycle load profile, package architecture and material properties to identify potential failure mechanisms and to prevent operational failures through robust design and manufacturing practices. The potential failure mechanisms and failure sites are identified in this paper for flip‐chip bonds, and an approach is presented to prevent the identified potential failure mechanisms by design. Finally, quality conformance issues are discussed to ensure a robust manufacturing process and qualification issues are addressed to evaluate the reliability of the designed flip‐chip bond.

The effects and implications of current developments in interconnection technology on print and fire thick film hybrid manufacture are discussed. Particular emphasis is given to the fact that in many cases new techniques complement rather than compete with film hybrids. Alternative substrates, semiconductor packaging, semicustom integrated circuits, surface mount technology and polymer thick film are all included in the paper. Conclusions are drawn which indicate that although these technologies are all of crucial importance they will not replace current thick film technology.