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The purpose of this paper is to analyze the individual steps during the printing of capacitor structures. The method of substrate preparation, the obtained roughness of conductive and dielectric layers are examined. Moreover, the capacitances of the obtained capacitors were examined.

Surface roughness and microscopic analysis were used to assess the quality of printed conductive structures. Two criteria were used to assess the quality of printed dielectric structures: the necessary lack of discontinuity of layers and minimal roughness. To determine the importance of printing parameters, a draft experimental method was proposed.

The optimal way to clean the substrate has been determined. The most important parameters for the dielectric layer (i.e. drop-space, table temperature, curing time and temperature) were found.

If dielectric layers are printed correctly, most problems with printing complex electronic structures (transistors, capacitors) will be eliminated.

The tests performed identified the most important factors for dielectric layers. Using them, capacitors of repeatable capacity were printed.

In the literature on this subject, no factors were found which were responsible for obtaining homogeneous dielectric layers.

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.

The purpose of this paper is to present the power noise characteristics of a multilayer printed circuit board (PCB) in which discrete capacitors have been embedded.

Embedded technology has been implemented on a multilayer PCB to enhance the performance and functionality and to decrease the power noise. Decoupling capacitors were directly positioned on the inner power planes of a board, which resulted in low‐loop inductance through the minimized length of the interconnection from the chips to the PCB's power delivery network.

A low‐noise PCB was successfully designed and fabricated using an embedding process for the discrete decoupling capacitors. It was demonstrated that such an approach offers lower interconnection inductance and quiet noise performance, including highly efficient propagation noise suppression at wideband frequencies.

Most conventional simulation techniques offer expectations for the signal characteristics on the time domain to minimize bit error rates in application systems. Further development work will focus on the integrated simulation models including the equivalent circuits for the transmission line and power noise effects to improve the accuracy of the signal performance.

This paper presents a new approach for improving generating and propagating noise performance through the use of an embedded decoupling capacitor design methodology.

This is the final part of an abridged version of the previously unpublished writings of Paul Eisler, universally acknowledged as the inventor of the printed circuit board and many other technical innovations. The content of the extracts presented has concentrated mainly on Dr Eisler's efforts in the field of printed circuit technology, followed by a few details of some of his other areas of invention.

As CPUs increase in performance, the number of passive components on the surface of circuit boards also increases dramatically. To reduce the number of components, as well as improve the electrical performance (i.e. reduce inductance), designers are increasingly embedding capacitive layers in the PCB. The majority of the products in use utilize reinforced epoxy laminates. These products are relatively easy to handle, but the thickness and Dk limit the effectiveness of the layer to perform as a capacitor. Other materials are being developed that are thinner (and thus increase capacitance), but either have problems with dielectric breakdown strength, handling or offer only a marginal improvement over existing materials. This paper describes new non‐reinforced substrates for use as embedded capacitance layers that address these issues. The material selection process, substrate processing and electrical performance are reviewed.

The purpose of this paper is to share valuable information about low‐cost microwave circuit research with academic and industrial communities that work, or want to work, in this field.

Screen‐printing technology has been chosen as the fabrication method because of simplicity and low costs. Different materials and printing parameters were tested in four generations of microstrip lines. After obtaining a satisfactory fabrication method, passive microwave components were printed, assembled, characterized and modeled.

Results demonstrated that the proposed low‐cost method allows fabricating low loss microstrip lines (15.63×10⁻³ dB/mm at 10 GHz), filters, inductors, and capacitors that work well up to 12 GHz.

Model accuracy of inductors and capacitors can be improved. The use of more precise calibration and de‐embedding techniques is necessary. More components can be fabricated and modeled to increase the flexibility and applicability of the proposed fabrication method.

The presented information can help limited budget companies and small educational institutions in electronics to fabricate microwave circuits at low costs. This is an excellent approach for students who want to learn how to make microwave frequency measurements and circuits without the need of expensive fabrication equipment and clean rooms.

The step‐by‐step fabrication method described in this paper allows fabricating different microwave components at low costs. The presentation of electrical models for each component completes the design‐fabrication cycle. As this information is gathered in a single source, it makes easier the incursion of new actors in the microwave field.

This paper aims to report the investigations of capacitors and inductors embedded into printed circuit boards (PCBs) designed in various layouts.

The research were focused on the components embedded into four-layer PCBs with different structures of the inner layers. Three special capacitive laminates for manufacturing of thin-film embedded capacitors and several types of coils in the form of a spiral, meander and solenoid are described. In addition, a part of the spiral-type coils was formed with an aperture in the center in which the magnetic core, made of soft magnetic composites’ material was placed to increase the coil inductance.

Various constructions of embedded capacitors and coils were designed and manufactured. Capacitance and loss tangent of capacitors to determine the repeatability of the production process were determined. Capacitor’s long-term stability analysis was performed by exposing test samples to elevated temperatures (70, 100 or 130°C), realized with the aid of heating plate, for at least 160 h. The temperature characteristics for the capacitance and loss tangent from 15 to 100°C were determined. Also the induction of different designs and layouts coils was determined.

The wide parameters’ characterization of capacitors and coils embedded into PCBs allow the analysis of their properties with regard to their practical application. The promising results of the realized measurements show that the capacitors and induction coils with studied structures can be widely used in the construction of embedded circuits into PCBs (e.g. filters, radio frequency identification systems and generators).

The purpose of this paper is to present work on the incorporation of capacitors into printed circuit boards (PCB) as a method to measure moisture content and follow moisture diffusion under ground planes.

PCBs were manufactured of FR‐4 incorporating different arrangements and sizes of capacitors formed between the tracks on adjacent layers of the PCB. The boards were placed in an 85°C and 85 per cent relative humidity (RH) environment to absorb moisture before baking at temperatures of 80, 110 or 125°C with the capacitance periodically measured. The effect of ground planes with different densities of plated and non‐plated through holes (PTH) has been studied by placing capacitors between ground planes.

Parallel plate capacitors embedded within a PCB showed a 10 per cent capacitance increase going from a dry state to being saturated with moisture in an 85°C and 85 per cent RH environment. The slow ingression of moisture under the capacitance planes meant that the measured capacitance change did not reflect the moisture content of the remainder of the board well. Capacitor plates with slots for the moisture to penetrate were also investigated, with the increase in capacitance found to show good correlation with the increase in board mass. In investigating moisture under ground planes, either by decreasing the hole density or by plating the holes, the time for moisture to diffuse out of the board was found to increase due to the lower exposed area on the PCB.

The paper illustrates a method that can be applied to PCB manufacturing to assess the moisture content of a board prior to reflow.

This paper aims to present combination of poly-jet technology and ink-jet technology in a multidisciplinary way in order to exploit advantages of these rapid prototyping techniques in manufacturing a demonstrator device – a variable interdigital capacitor.

The platform of 3D complex geometry, with optimized design and cavity under the capacitor's fingers (plates), was fabricated using Alaris 3D printer, whereas silver conductive segments were fabricated using Dimatix ink-jet printer and thanks to the mechanical flexibility the platform has been covered using these segments.

When one side of the capacitor's structure changes angular position (in the range from 0 to 90°) with reference to the fixed part, the variation in total capacitance is obtained. The total capacitance decreases (in the range from 20.2 to 1.5 pF) with decrease in effective overlapping area for the variation of angular position from 0 to 90° The maximum measured tuning ratio for the proposed design of the variable capacitor was 13.5:1.

Presented variable capacitor can be used for detection angular position in the range from 0 to 90°.

The new horizon has been opened combining the rapid prototyping equipment in electronics and mechanical engineering in an interdisciplinary way to manufacture, for the first time, variable capacitor using poly-jet and ink-jet technologies. These techniques do not require higher mask counts which makes the fabrication fast and cost-effective.

This work, for the first time, demonstrates the combination of ALARIS 30 3D printer and Dimatix DMP-3000 materials deposition printer in order to fabricate the interdigital capacitor with complex 3D geometry. ALARIS 3D printer has been used for manufacturing plastic platform (with the possibility to precisely adjust angular position of one comb related to another) and Dimatix printer has been used to print silver conductive inks on flexible substrates (Kapton film), and this mechanically flexible structure was used to cover capacitor's fingers on the platform (assembly).

This paper will focus on the work which was carried out under the Brite‐EuRAM funded project, COMPRISE (BE 96‐3371), the objective of which was to develop new materials and manufacturing processes to embed passive components (resistors, inductors, capacitors) within printed wiring structures fabricated from laminate materials. For the realisation of integrated resistors, a commercially available planar resistor material is incorporated in different test structures. The technology consists of a copper foil of standard thickness on which a resistive layer is deposited by means of electroless plating. For the realisation of capacitors in multi‐layered PCB structures, significant progress was made in the development and fabrication of very thin laminates. Higher dielectric constants of these laminate materials enable the increase of the capacitance per unit area. For inductors, both aircore (no magnetic material) and magnetic core components have been investigated.