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A laser ablation technique has been used to fabricate conductor patterns on a 96% alumina substrate to evolve passive fine‐line components and structures. This paper reports the method of fabricating better fine‐line passive components for hybrid microelectronics application. The effect of a laser beam on the conductor and 96% alumina (Al₂O₃) substrate was studied in detail. Three predominant structures — namely debris, ablation border and irradiated bottom layer — were seen on the patterns. A detailed study of the dendritic growth caused by electrochemical migration on conductor lines fabricated by conventional screen printing and by laser ablation techniques is also reported.

On Wednesday 13th October, 1982, the Cahners Exposition Group, proprietors of the Internepcon Exhibition, sponsored and organised a special banquet to honour two individuals who had made major contributions to their respective Industries.

Thick film symmetrical LC cells with two pairs of terminations were printed on alumina using PdAg paste and crossover dielectric. Planar inductors such as meander, spiral, bispiral, and solenoid in plane were distributed over planar capacitors such as sandwich, interdigitated and segmented. Attenu‐ation and Smith charts of symmetrical EMI LC cells were measured on network analyzer in the range of 1 MHz to 3 GHz. Two or three main LC cells were joined in series to sum attenuation. The obtained results were compared mutually, at first, and than with the cubic (chip) EMI LC filters. The obtained EMI noise suppression was similar, but the filter band of thick film LC cells was much wider.

The purpose of this paper is to review traditional hermeticity test methods when applied to typical micro‐electro‐mechanical systems (MEMS) cavity volumes and to propose potential solutions.

Standards for traditional testing have been applied to typical MEMS cavity volumes and the resulting issues of range and sensitivity discussed. In situ test structures have been designed and fabricated with access to the internal cavities to allow characterisation of the structures as a function of pressure.

The ultra low leak rates necessary to guarantee hermeticity of MEMS cannot be measured using traditional methods. Optical test methods are possible although in situ test structures currently provide the greatest sensitivity. A portfolio of test techniques is required to allow accurate hermeticity testing of MEMS.

This paper provides a starting point for further investigation into several methods of MEMS hermeticity testing.

This paper provides a review of the limitations of traditional testing and proposals for future testing as the trend towards smaller volume packaging continues.

This paper aims to compare and study two-dimensional (2D) and three-dimensional (3D) computational fluid dynamics simulation results of gas flow velocity in a convection reflow oven and show the differences of the different modeling aspects. With the spread of finer surface-mounted devices, it is important to understand convection reflow soldering technology more deeply.

Convection reflow ovens are divided into zones. Every zone contains an upper and a lower nozzle-matrix. The gas flow velocity field is one of the most important parameters of the local heat transfer in the oven. It is not possible to examine the gas flow field with classical experimental methods due to the extreme circumstances in the reflow oven. Therefore, numerical simulations are necessary.

The heat transfer changes highly along the moving direction of the assembly, and it is nearly homogeneous along the traverse direction of the zones. The gas flow velocity values of the 2D model are too high due to the geometrical distortions of the 2D model. On the other hand, the calculated flow field of the 2D model is more accurate than in the 3D model due to the finer mesh.

Investigating the effects of tall components on a printed wiring board inside the gas flow field and further analysis of the mesh size effect on the models.

The presented results can be useful during the design of a simulation study in a reflow oven (or in similar processes).

The presented results provide a completely novel approach from the aspect of 2D and 3D simulations of a convection reflow oven. The results also reveal the heat transfer differences.