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This paper addresses materials and processes for printed wiring board compatible embedded capacitors using polymer/ceramic nanocomposites and hydrothermal barium titanate. Polymers allow low temperature fabrication appropriate to the board (MCM‐L) technology. The lower dielectric constants of the commercially available polymers can be greatly compensated by incorporating higher permittivity ceramic fillers. Materials requirements for higher capacitance density (>30 nF/cm²) have been addressed through implementation of a novel low‐temperature processable hydrothermal barium titanate film on a patterned titanium foil laminated to the PWB. Application of hydrothermal grown barium titanate is currently being evaluated using a multi‐layer system‐on‐package demonstration.

This study aims to fabricate complex ceramic tetrahedron structures, which are challenging to produce by more conventional methods such as injection molding. To achieve this aim, thermoplastic-ceramic composite filaments were developed and printed with unmodified, consumer-grade, fused deposition modelling (FDM) printers instead.

Al₂O₃ ceramic powder was mixed with ethylene vinyl acetate polymer as a binder (50 Vol.- per cent) to form a filament with a constant diameter of 1.75 mm. After the printing and thermal treatment stages, the shrinkage and mechanical properties of cuboid and tetrahedron structures were investigated.

The shrinkage of the parts was found to be anisotropic, depending on the orientation of the printing pattern, with an increase of 2.4 per cent in the (vertical) printing direction compared to the (horizontal) printing layer direction. The alignment of the ceramic particle orientations introduced by FDM printing was identified as a potential cause of the anisotropy. This study further demonstrates that using a powder bed during the thermal debinding process yields sintered structures that can withstand twice the compressive force.

Ceramic FDM had previously been used primarily for simple scaffold structures. In this study, the applicability of ceramic FDM was extended from simple scaffolds to more complex geometries such as hollow tetrahedra. The structures produced in this study contain dense parts printed from multiple contiguous layers, as compared to the open structures usually found in scaffolds. The mechanical properties of the complex ceramic parts made by using this FDM technique were also subjected to investigation.

Conventional machining methods for fabricating piezoelectric components such as ultrasound transducer arrays are time-consuming and limited to relatively simple geometries. The purpose of this paper is to develop an additive manufacturing process based on the projection-based stereolithography process for the fabrication of functional piezoelectric devices including ultrasound transducers.

To overcome the challenges in fabricating viscous and low-photosensitive piezocomposite slurry, the authors developed a projection-based stereolithography process by integrating slurry tape-casting and a sliding motion design. Both green-part fabrication and post-processing processes were studied. A prototype system based on the new manufacturing process was developed for the fabrication of green-parts with complex shapes and small features. The challenges in the sintering process to achieve desired functionality were also discussed.

The presented additive manufacturing process can achieve relatively dense piezoelectric components (approximately 95 per cent). The related property testing results, including X-ray diffraction, scanning electron microscope, dielectric and ferroelectric properties as well as pulse-echo testing, show that the fabricated piezo-components have good potentials to be used in ultrasound transducers and other sensors/actuators.

A novel bottom-up projection system integrated with tape casting is presented to address the challenges in the piezo-composite fabrication, including small curing depth and viscous ceramic slurry recoating. Compared with other additive manufacturing processes, this method can achieve a thin recoating layer (as small as 10 μm) of piezo-composite slurry and can fabricate green parts using slurries with significantly higher solid loadings. After post processing, the fabricated piezoelectric components become dense and functional.

To synthesise calcium titanate with a perovskite structure as an anticorrosion pigment for metal protecting paints.

Calcium titanate was synthesised from titanium dioxide and calcium carbonate at high temperature. The pigment obtained was characterised by means of X‐ray diffraction, particle size distribution measurement and scanning electron microscopy. The pigment obtained was further characterised with regard to the parameters required for paint formulation; its specific mass was determined by oil consumption and critical pigment volume concentration. The synthesised calcium titanate was used to prepare epoxy coatings with varying contents of the anticorrosion pigment. The coating was tested for physical‐mechanical properties and in corrosive atmospheres. The results were compared with titanium dioxide that served as a starting material for calcium titanate preparation.

Calcium titanate was prepared from materials that do not add any impurities to the anticorrosion properties of the pigment. It was identified that calcium titanate of perovskite structure is a highly efficient anticorrosion pigment for paints.

Calcium titanate can be utilised for the preparation of anticorrosion paints to protect metal bases from corrosion.

The method of synthesising calcium titanate as an anticorrosion pigment is new. The literature has not yet described the use of calcium titanate as a pigment with inhibitive properties in paints. From an ecologic standpoint, the application of a new anticorrosion pigment for paints presents a highly positive trend.

There has been increasing interest in the development of printable electronics to meet the growing demand for low‐cost, large‐area, miniaturized, flexible and lightweight devices. The purpose of this paper is to discuss the electronic applications of novel printable materials.

The paper addresses the utilization of polymer nanocomposites as it relates to printable and flexible technology for electronic packaging. Printable technology such as screen‐printing, ink‐jet printing, and microcontact printing provides a fully additive, non‐contacting deposition method that is suitable for flexible production.

A variety of printable nanomaterials for electronic packaging have been developed. This includes nanocapacitors and resistors as embedded passives, nanolaser materials, optical materials, etc. Materials can provide high‐capacitance densities, ranging from 5 to 25 nF/in², depending on composition, particle size, and film thickness. The electrical properties of capacitors fabricated from BaTiO₃‐epoxy nanocomposites showed a stable dielectric constant and low loss over a frequency range from 1 to 1,000 MHz. A variety of printable discrete resistors with different sheet resistances, ranging from ohm to Mohm, processed on large panels (19.5×24 inches) have been fabricated. Low‐resistivity materials, with volume resistivity in the range of 10⁻⁴‐10⁻⁶ ohm cm, depending on composition, particle size, and loading, can be used as conductive joints for high‐frequency and high‐density interconnect applications. Thermosetting polymers modified with ceramics or organics can produce low k and lower loss dielectrics. Reliability of the materials was ascertained by (Infrared; IR‐reflow), thermal cycling, pressure cooker test (PCT) and solder shock testing. The change in capacitance after 3× IR‐reflow and after 1,000 cycles of deep thermal cycling between −55°C and +125°C was within 5 per cent. Most of the materials in the test vehicle were stable after IR‐reflow, PCT, and solder shock.

The electronic applications of printable, high‐performance nanocomposite materials such as adhesives (both conductive and non‐conductive), interlayer dielectrics (low‐k, low‐loss dielectrics), embedded passives (capacitors and resistors), and circuits, etc.. are discussed. Also addressed are investigations of printable optically/magnetically active nanocomposite and polymeric materials for fabrication of devices such as inductors, embedded lasers, and optical interconnects.

A thin film printable technology was developed to manufacture large‐area microelectronics with embedded passives, Z‐interconnects and optical waveguides, etc. The overall approach lends itself to package miniaturization because multiple materials and devices can be printed in the same layer to increase functionality.

Material formulation, structuring and modification are key to increasing the unit volume complexity and density of next generation electronic packaging products. Laser processing is finding an increasing number of applications in the fabrication of these advanced microelectronic devices. The purpose of this paper is to discuss the development of new laser‐processing capabilities involving the synthesis and optimization of materials for tunable device applications.

The paper focuses on the application of laser processing to two specific material areas, namely thin films and nanocomposite films. The examples include BaTiO₃‐based thin films and BaTiO₃ polymer‐based nanocomposites.

A variety of new regular and random 3D surface patterns are highlighted. A frequency‐tripled Nd:YAG laser operating at a wavelength of 355 nm is used for the micromachining study. The micromachining is used to make various patterned surface morphologies. Depending on the laser fluence used, one can form a “wavy,” random 3D structure, or an array of regular 3D patterns. Furthermore, the laser was used to generate free‐standing nano and micro particles from thin film surfaces. In the case of BaTiO₃ polymer‐based nanocomposites, micromachining is used to generate arrays of variable‐thickness capacitors. The resultant thickness of the capacitors depends on the number of laser pulses applied. Micromachining is also used to make long, deep, multiple channels in capacitance layers. When these channels are filled with metal, the spacings between two metallized channels acted as individual vertical capacitors, and parallel connection eventually produce vertical multilayer capacitors. For a given volume of capacitor material, theoretical capacitance calculations are made for variable channel widths and spacings. For comparison, calculations are also made for a “normal” capacitor, that is, a horizontal capacitor having a single pair of electrodes.

This technique can be used to prepare capacitors of various thicknesses from the same capacitance layer, and ultimately can produce variable capacitance density, or a library of capacitors. The process is also capable of making vertical 3D multilayer embedded capacitors from a single capacitance layer. The capacitance benefit of the vertical multilayer capacitors is more pronounced for thicker capacitance layers. The application of a laser processing approach can greatly enhance the utility and optimization of new materials and the devices formed from them.

Laser micromaching technology is developed to fabricate several new structures. It is possible to synthesize nano and micro particles from thin film surfaces. Laser micromachining can produce a variety of random, as well as regular, 3D patterns. As the demand grows for complex multifunctional embedded components for advanced organic packaging, laser micromachining will continue to provide unique opportunities.

AMONG the industries represented were aircraft, motor, rubber, iron and steel, oil, glass, instrument manufacturers, the film industry and electricity supply. Countries sending representatives were U.S.A., Canada, France, Holland, Australia, India, Pakistan and Eire. A distinguished visitor contributing to the discussions was Dr Mervin Kelly, head of Bell Telephone Laboratories, U.S.A.

Purpose is to design the energy harvesters and to know the limit of the application of load on the PZT material. Fatigue failures of the designed products is merely bothering the modern engineers and scientists for the research communities of all fields. Especially in the field of Micro Electromechanical Systems (MEMS), durability of low power systems is very important under the climates of both at high temperature and low temperature zones. And also continuous electrical power requirement is important for the MEMS and wireless sensor networks. Electricity is the greatest crisis in the world on one side and on the other side, durability of smart devices such as mobile phones, laptops, compact devices, computer spare parts are unrecyclicable batteries for reducing the rate of pollution in the environment.

By considering these problems, authors have taken up a research in finding the first fatigue characteristics, which are fatigue failure and durability of ferroelectric material as lead zirconate titanate, and then designed the scavenging device by using harmonically excited vibrations for getting optimum power output which is about 15.6 mW.

Under the resonance operated condition at the frequency of about 50 Hz, a prototype of scavenging device is about 90 V AC peak-to-peak voltage and the durability of scavenging device is 9.715 years.

Durability of PZT at different environmental conditions plays a very important role for the continuous function of low power devices. The output of PZT may change when the working time increases in addition with the mechanical properties.