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The purpose of this paper is to present an analytical approach to find the reduction in the required number of surface mount capacitors by the use of embedded capacitors in decoupling applications.

The analytical model used to perform decoupling is cavity model from theory of microstrip antenna and N‐port impedance matrix. The methodology involves addition of decoupling capacitors between the power and the ground plane such that the impedance between ports on the power‐ground plane becomes lower than the target impedance at that frequency. A case study is presented in which a 0.3 m×0.3 m power‐ground plane is decoupled by using various combinations of surface mount capacitors and embedded capacitors in the frequency range of 0.001‐1 GHz and at a target impedance of 0.1, 0.01, and 0.001 Ω. The total number of surface mount capacitors are compared in each case.

Use of embedded planar capacitors with a thin dielectric (about 8 mm) dampened board resonances at high frequency, as compared to a thick dielectric. Embedded capacitors are found to reduce the number of surface mount capacitors when the target impedance is low and the operating frequency is high.

The methodology discusses in this paper is applicable to a simplified power‐ground plane (which has no cut‐outs and is rectangular in shape) as compared to actual digital circuits.

This methodology can be used as a quick preliminary tool to evaluate the decrease in the number of surface mount capacitors (by the use of embedded capacitors) as compared to complex and time consuming electromagnetic solvers.

Embedded passives account for a very large part of today's electronic assemblies. This is particularly true for products such as cellular phones, camcorders, computers, and several critical defence devices. Market pressures for new products with more features, smaller size and lower cost demand smaller, compacter, simpler substrates. An obvious strategy is to reduce the number of surface mounted passives by embedding them in the substrate. In addition, current interconnect technology to accommodate surface mounted passives imposes certain limits on board design which constrain the overall system speed. Embedding passives is one way to minimize the functional footprint while at the same time improving performance. The purpose of this paper is to describe the development of a thin film technology based on ferroelectric‐epoxy polymer‐based flake‐free resin coated copper capacitive (RC3) nanocomposites to manufacture multilayer embedded capacitors.

This paper discusses thin film technology based on RC3 nanocomposites. In particular, recent developments in high capacitance, large area, thin film passives, and their integration in system in a package (SiP) are highlighted.

A variety of RC3 nanocomposite thin films ranging from 8 to 50 microns thick were processed on copper substrates by liquid coating. Multilayer embedded capacitors resulted in high capacitances of 16‐28 nF. The fabricated test vehicle also included two embedded resistor layers with resistances in the range of 15 Ω to 100 kΩ. To enable high performance devices, an embedded resistor must meet certain tolerances. The embedded resistors can be laser trimmed to a tolerance of <5 percent, which is usually acceptable for most applications. An extended embedded passives solution has been demonstrated, both through its high wireability designs and package performance, to be perfectly suited for SiP applications.

This case study designed and fabricated an eight layer high density internal passive core and subsequently applied fine geometry three buildup layers to form a 3‐8‐3 structure. The passive core technology is capable of providing up to six layers of embedded capacitance and could be extended further.

A thin film technology based on ferroelectric‐epoxy polymer‐based flake‐free RC3 nanocomposites was developed to manufacture multilayer embedded capacitors. The overall approach lends itself to package miniaturization because capacitance can be increased through multiple layers and reduced thickness to give the desired values in a smaller area.

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 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).

Embedded passives technologies can provide benefits of size, performance, cost, and reliability to high density, high‐speed designs. A number of embedded passive technology solutions are available to the designer. Based on our experience with Rohm and Haas's thin‐film, high‐ohmic, InSite^TM embedded resistor materials (500 and 1000 Ω/sq), this paper provides some guidelines for selecting the appropriate embedded resistor technology and implementing it at a board fabricator. The design of embedded resistors, and the trade‐offs between resistor size, tolerance, and capability of board fabrication processes, are analyzed in detail. This paper also discusses selection of the appropriate embedded capacitor technology and introduces some initial results on Rohm and Haas's thin‐film, high‐D_k, InSite embedded capacitor material (200 nF/cm²).

With the advent of new materials and technologies that enable passive components to be embedded within electronic substrates, one key question that arises is: under what circumstances (and for what type of applications) is it economically viable to consider using embedded passives? The economic issues that must be considered consist of a combination of manufacturing costs and throughputs, and non‐manufacturing life cycle costs. This paper discusses the assessment of manufacturing costs associated with embedding resistors and capacitors in printed circuit boards and provides cost modeling results for an avionics board. The discussion is extended to include optimizing the specific embedded passive content in a board and design for production modeling when embedded passives are present. Life cycle cost issues are also qualitatively discussed.

All capacitor dielectric materials, whether used for discrete or embedded applications, can be grouped into two general categories: paraelectric and ferroelectric. Ferroelectrics generally exhibit much higher dielectric constants, but are also less stable with regard to temperature, frequency, voltage, time and film thickness. There are dozens of each of these materials that have been used in discrete capacitors and about ten that are either available for use in embedded capacitors or will soon be marketed for that purpose. The commercialized materials can be broken down into four sub‐categories: thick‐film polymers, ferroelectric powder in polymer binders, thin‐film paraelectrics, and thick‐film ferroelectrics. These four classifications are evaluated with regard to their electrical performance, ease of fabrication, and suitability for specific applications.

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.

The purpose of this study was the use of embedded components technology and innovative concepts of the printed circuit board (PCB) for electronic modules containing field-programmable gate array (FPGA) devices with a large number of pins (e.g. Virtex 6, FF1156/RF1156 package, 1,156 pins).

In the multi-layered boards, embedded passive components that support FPGA device input/output (I/O), such as blocking capacitors and pull-up resistors, were used. These modules can be used in rapid design of electronic devices. In the study, the MC16T FaradFlex material was used for the inner capacitive layer. The Ohmega-Ply RCM 25 Ω/sq material was used to manufacture pull-up resistors for high-frequency pins. The embedded components have been connected to pins of the FPGA component by using plated-through holes for capacitors and blind vias for resistors. Also, a technique for a board-to-board joining, by using castellated terminations, is described.

The fully functional modules for assembly of the FPGA were manufactured. Achieved resistance of embedded micro resistors, as small as the smallest currently used surface-mount device components (01005), was below required tolerance of 10 per cent. Obtained tolerance of capacitors was less than 3 per cent. Use of embedded components allowed to replace the pull-up resistors and blocking capacitors and shortens the signal path from the I/O of the FPGA. Correct connection to the castellated terminations with a very small pitch was also obtained. This allows in further planned studies to create a full signal distribution system from the FPGA without the use of unreliable plug connectors in aviation and space technology.

This study developed and manufactured several innovative concepts of signal distribution from printed circuit boards. The signal distribution solutions were integrated with embedded components, which allowed for significant reduction in the signal path. This study allows us to build the target object that is the module for rapid design of the FPGA device. Usage of a pre-designed module would lessen the time needed to develop a FPGA-based device, as a significant part of the necessary work (mainly designing the signal and power fan-out) will already be done during the module development.

The purpose of this paper is to investigate the basic functional parameters of passive embedded components in printed circuit boards (PCBs) under environmental exposures such as thermal-humidity and thermal exposure.

The investigations were based on the thin-film resistors made of NiP alloy, thick-film resistors made of carbon or carbon–silver inks, embedded capacitors made of FaradFlex materials and embedded inductor made in various configurations. The capacitors and thin- and thick-film resistors were tested in the climatic chamber in conditions of thermal-humidity exposure at 85°C and 85 per cent RH for 500 h. The embedded inductors were tested in two different environmental conditions: thermal-humidity exposure at 60°C and 95 per cent RH, and thermal exposure at 150°C and additionally at the temperature in the range of +25°C to +150°C.

Studies show that in the case of embedded capacitors, the changes caused by exposure to thermal-humidity are durable and lead to the capacity increase. The embedded thin-film resistors behave in the same manner, whereas the thick-film resistors were the least resistant to the conditions of exposure. Most of the polymer thick-film resistors have been damaged. The changes of coils' properties during aging are small, and what is most important is that, after some time of exposure, their parameters stabilize at a particular level. The changes resulting from the increase in temperature are typically related to the change of material resistance (Cu) of which coils are made, and as such, they cannot be avoided but they can be predicted.

The realized studies allowed determination of the properties of the embedded passive elements with respect to specific environmental exposures. The studies show that embedded resistors can be used interchangeably with chip passive elements. It allows saving the area on the surface of PCB, occupied by these passive elements, for assembly of active elements integrated circuits (ICs) and thus enabling the miniaturization of electronic devices.

The knowledge about the behavior of the operating parameters of embedded components, considering the environmental conditions, allows for development of more complex systems with integrated PCBs.