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To investigate the effect of the metallization and solder mask materials on the solder joint reliability of low temperature co‐fired ceramic (LTCC) modules.

The fatigue performance of six LTCC/PCB assembly versions was investigated using temperature cycling tests in the −40‐125°C and 20‐80°C temperature ranges. In order to eliminate fatigue cracking in the LTCC module itself, large AgPt‐metallized solder (1 mm) lands with organic or co‐fired glaze solder masks, having 0.86‐0.89 mm openings, were used. The performance of these modules was compared to that of AgPd‐metallized modules with a similar solder land structure. The joint structures were analysed using resistance measurements, scanning acoustic microscopy, SEM/EDS investigation, and FEM simulations.

The results showed that failure distributions with Weibull shape factor (β) values from 8.4 to 14.2, and characteristic life time (θ) values between 860 and 1,165 cycles were achieved in AgPt assemblies in the −40‐125°C temperature range. The primary failure mechanism was solder joint cracking, whereas the AgPd‐metallized modules suffered from cracking in the ceramic. In the milder test conditions AgPd‐metallized modules showed better fatigue endurance than AgPt‐metallized modules.

This paper proves that the cracking in ceramic in the harsh test condition can be eliminated almost completely by using AgPt metallization instead of AgPd metallization in the present test module structure.

Ongoing reductions in dielectric thickness for metallized AC capacitors, has resulted in a shift away from pure aluminium coatings for capacitor materials to be used in higher voltage applications. Metallized electrodes such as zinc with silver prenucleation, zinc/aluminium composites and aluminium bilayers are now required for AC capacitors. This paper will discuss the design aspects of a vacuum web coater to provide this wider range of requirements.

Enclosed arc metallizing spray gun. Metallizing Co. of America has developed a new metallizing gun, the Mogul Enclosed Arc Spray Gun Model HK‐400. New features claimed are: it's lightweight and highly manoeuvrable, enabling the user to do many more metallizing repairs in less time than older, obsolete guns.

Over the past ten years a non‐contact resistance monitor has been developed for measuring the deposit above each evaporator on resistance‐heated evaporative metallizers. This is the eddy current type. The flux from an RF coil links with the metallized film. The resultant induced current in the film, which is proportional to the thickness of the deposit, is measured (see Figure 1). Normally, sensor coils are positioned in line with evaporators. The RF sensor head is located next to an insulated roller carrying the metallized film.

Hybrid manufacturers are uncertain as to whether laser‐drilled holes on 96% alumina are suitable for mixed‐bonded thick film conductor metallisation, or whether they require further treatment before metallisation if reliable circuitry is to be produced. Moreover, although the metallisation of holes on ceramic through the use of screen printed thick films is fairly common in the hybrid industry, this paper shows that published information on this topic is scant, at times contradictory, and, because of proprietary constraints, generally of little use. The authors report on an extensive study in which both as‐laser‐drilled holes and thermally‐treated laser‐drilled holes are metallised using a mixed bonded Pd‐Ag conductor paste. Both encapsulated and non‐encapsulated metallised holes are then subjected to various accelerated life tests, followed by ‘power‐up’ tests to the extreme of circuit destruction. An account is also given of a printing set‐up which allows volume production of printed through‐holes without the need for special skill or attention on the part of the printing operator.

This paper seeks to deal with the computation of time‐harmonic electric potentials, currents, and surface charge distributions inside self‐healing metallized film capacitors in three dimensions. A 50 Hz exciting voltage is applied at contacts.

Extreme aspect ratios warrant dimensional reduction: the metallization is modelled as a 2D shell. This greatly reduces computational costs and makes possible an excellent resolution of the geometry. An integro‐differential equation for the complex amplitudes of the electric potential and surface charge densities on this shell is derived and discretized by means of boundary elements.

Adaptive cross approximation and H‐matrix technology is employed for matrix compression and preconditioning of iterative solvers. This permits one to use fine surface meshes and achieve satisfactory accuracy as demonstrated in numerical experiments.

The model is based on an electroquasistatic approach; thus it is valid for low frequencies only.

Numerical experiments of sophisticated real‐life capacitor‐designs show the efficacy of the method for industrial applications.

A novel model was developed and implemented for the 3D electric field computation inside metallized film capacitors in the frequency domain.

The protection by metallizing of iron and steel against heat corrosion has proved so successful in the past that it is rapidly becoming the accepted standard in many industries. It is well recognised that iron‐aluminium alloys offer resistance to oxidation at elevated temperatures; they are, however, hard and brittle and consequently difficult to fabricate. As a result, they have been used most economically so far in the form of a relatively thin coating or layer on steel.

Metallising Truck. A sturdy, completely portable metallising truck has been developed which is designed to give maximum mobility and efficiency to a metallising installation, and permits the movement of all normal metallising equipment, accessories and supplies necessary to do a good job whenever and wherever required.

This paper aims to perform thermal and mechanical characterization for silver-based sintered thermal joints. Layer quality affects thermal and mechanical performance, and it is important to achieve information about how materials and process parameters influence them.

Thermal investigation of the thermal joints analysis method was focused on determination of thermal resistance, where temperature measurements were performed using infrared camera. They were performed in two modes: steady-state analysis and dynamic analysis. Mechanical analysis based on measurements of mechanical shear force. Additional characterizations based on X-ray image analysis (image thresholding), optical microscope of polished cross-section and scanning electron microscope image analysis were proposed.

Sample surface modification affects thermal resistance. Silver metallization exhibits the lowest thermal resistance and the highest mechanical strength compared to the pure Si surface. The type of dynamic analysis affects the results of the thermal resistance.

Investigation of the layer quality influence on mechanical and thermal performance provided information about different joint types.

In recent years considerable research has been carried out on the metallising of plastics. It has long been realised that there could be many important industrial applications, especially in the field of corrosion resistance, if the surface hardness and moisture permeability of plastics could be improved by a durable coating of metal. In the purely decorative department, where appearance is more important than length of service, it must be admitted that the demand has been fairly satisfactorily met by such processes as vacuum deposition, with or without electroplating. In the industrial sphere, however, the picture has not been quite so encouraging and the product has fallen short in many ways.