No description available.

Duas ferramentas para modelamento de indutores planares, retangulares e integrados e as equações analíticas implementadas em um software, foram estudadas e analisadas, para determinar qual é a mais apropriada, ou seja, aquela que fornece os resultados mais próximos de medidas experimentais, com menor custo, maior velocidade, etc. Indutores planares integrados apresentam limitações severas em seu uso. As duas principais são: o baixo valor do fator de qualidade, que limita o ganho e a banda nos amplificadores e filtros que os utilizam; e a dificuldade no seu modelamento e na determinação dos parâmetros que os caracterizam. Apesar das dificuldades no uso destes dispositivos, eles são aplicados em diversos sistemas, tais como transceptores que operam em rádio freqüências. Nestes sistemas, indutores são necessários e sua integração é essencial para se obter soluções completamente integradas. As ferramentas estudadas para o modelamento de indutores neste trabalho foram: ASITIC e SONNET. As equações analíticas foram implementadas no MATLAB. A comparação entre as ferramentas e as equações foi feita por meio de cinco indutores construídos e medidos. Os indutores foram fabricados em tecnologia CMOS de 0,35 µm com quatro camadas de metal. Para realizar a correta comparação entre os resultados simulados e as medidas elétricas, reduzindo ao máximo a interferência de elementos parasitas (inclusos pelos pads), os indutores foram inseridos em estruturas de teste. Estruturas de caracterização apropriadas foram também projetadas para permitir a eliminação do efeito das estruturas de teste sobre as medidas. / Two modeling tools for integrated planar square inductors and one software implementing analytical relations, were studied and analyzed, to determine which is the most appropriate, that is, the tools that will supply the closest results to experimental measurements with, lower costs, higher speed, etc. Integrated planar inductors present severe limitations in their use. The two main limitations are: the low value of the quality factor, that affects the gain and the band of amplifiers and filters where they are used; and the difficulty in modeling and determining of their parameters. Inspire of the difficulties in the use of these devices, they are applied in many systems, such as transceivers that operate in radio frequency. In these systems, inductors are necessary and their integration is essential to obtain completely integrated solutions. In this work the studied tools for inductor modeling were: ASITIC and SONNET. The analytical relations were implementing in MATLAB. The comparisons between the tools were made through five implemented and measured inductors. The inductors were fabricated in a CMOS 0.35 µm technology with four metal layers. In order to carry out the correct comparison between the modeled results and the electric measurements, minimizing the interference of pad parasitic elements, the inductors were inserted within appropriate test structures. Characterization structures were also implemented to allow the elimination of the test structure effects on the measurements.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 95-97). Also available in electronic version. Access restricted to campus users.

Duas ferramentas para modelamento de indutores planares, retangulares e integrados e as equações analíticas implementadas em um software, foram estudadas e analisadas, para determinar qual é a mais apropriada, ou seja, aquela que fornece os resultados mais próximos de medidas experimentais, com menor custo, maior velocidade, etc. Indutores planares integrados apresentam limitações severas em seu uso. As duas principais são: o baixo valor do fator de qualidade, que limita o ganho e a banda nos amplificadores e filtros que os utilizam; e a dificuldade no seu modelamento e na determinação dos parâmetros que os caracterizam. Apesar das dificuldades no uso destes dispositivos, eles são aplicados em diversos sistemas, tais como transceptores que operam em rádio freqüências. Nestes sistemas, indutores são necessários e sua integração é essencial para se obter soluções completamente integradas. As ferramentas estudadas para o modelamento de indutores neste trabalho foram: ASITIC e SONNET. As equações analíticas foram implementadas no MATLAB. A comparação entre as ferramentas e as equações foi feita por meio de cinco indutores construídos e medidos. Os indutores foram fabricados em tecnologia CMOS de 0,35 µm com quatro camadas de metal. Para realizar a correta comparação entre os resultados simulados e as medidas elétricas, reduzindo ao máximo a interferência de elementos parasitas (inclusos pelos pads), os indutores foram inseridos em estruturas de teste. Estruturas de caracterização apropriadas foram também projetadas para permitir a eliminação do efeito das estruturas de teste sobre as medidas. / Two modeling tools for integrated planar square inductors and one software implementing analytical relations, were studied and analyzed, to determine which is the most appropriate, that is, the tools that will supply the closest results to experimental measurements with, lower costs, higher speed, etc. Integrated planar inductors present severe limitations in their use. The two main limitations are: the low value of the quality factor, that affects the gain and the band of amplifiers and filters where they are used; and the difficulty in modeling and determining of their parameters. Inspire of the difficulties in the use of these devices, they are applied in many systems, such as transceivers that operate in radio frequency. In these systems, inductors are necessary and their integration is essential to obtain completely integrated solutions. In this work the studied tools for inductor modeling were: ASITIC and SONNET. The analytical relations were implementing in MATLAB. The comparisons between the tools were made through five implemented and measured inductors. The inductors were fabricated in a CMOS 0.35 µm technology with four metal layers. In order to carry out the correct comparison between the modeled results and the electric measurements, minimizing the interference of pad parasitic elements, the inductors were inserted within appropriate test structures. Characterization structures were also implemented to allow the elimination of the test structure effects on the measurements.

Modeling and simulation results for two types of 150 μm height air suspended inductors proposed for LIGA fabrication are presented. The inductor substrates used model the TSMC 0.18 μm CMOS/BiCMOS substrates. The RF performance between the suspended structure and the unsuspended counterpart are compared and the advantage of the suspended structures is explored. The potential of LIGA for fabricating high suspended inductors with good performance and for combining these with CMOS/BiCMOS is demonstrated.

Modeling and simulation results for two types of 150 μm height air suspended inductors proposed for LIGA fabrication are presented. The inductor substrates used model the TSMC 0.18 μm CMOS/BiCMOS substrates. The RF performance between the suspended structure and the unsuspended counterpart are compared and the advantage of the suspended structures is explored. The potential of LIGA for fabricating high suspended inductors with good performance and for combining these with CMOS/BiCMOS is demonstrated.

No description available.

D.Ing. / Changes in the preferred technologies used in modem switched mode power supplies are driven by the need for a decrease in cost of manufacturing while maintaining the highest possible power density. Modem materials allow smaller components to be manufactured without affecting their electromagnetic properties but thermal problems still impair efforts to further reduce their size. Increased switching frequencies cause increased conductor and core losses in magnetic components such as inductors and transformers. Amongst other advantages the increased surface area of low-profile planar structures allow better removal of the heat generated in the component and this work reevaluates conductor optimization for specific planar inductor windings. Conductor optimization has been a topic thoroughly investigated over the last few decades and these techniques have been adopted for planar winding design. It will be shown that the process involved in the manufacturing of helical planar windings allows further exploitation of the basic optimization process. A per-layer optimization technique, earlier proposed by other researchers and deemed impractical at the time, is revised and it is shown here that it can be successfully implemented in the chosen winding type. The per-layer optimization is also extended to accommodate non-sinusoidal current waveforms in this work. Other facets of loss reduction are also addressed. Windings are shaped in the region of air gaps in magnetic circuits to reduce the losses caused by the fringing flux intersecting the conductors but since the shaping influences both the ac-resistance and dc-resistance of the winding an optimization process is required to find the optimal conductor arrangement. Contributions are made with regard to speeding up the process of finding the optimal layout of conductors around the air gap by devising a simple model for the flux distribution of the fringing flux. The effect of combining the per-layer optimization technique with these shaping techniques is exploited to its full potential in this work and contributes largely to loss reduction in helical inductor windings carrying currents containing ac- and dc components. The optimization time is reduced by allowing winding shaping while maintaining the dc-resistance of each layer. The optimal winding shape then becomes a function of the window constraints for a chosen core rather than finding it through conventional methods. Case studies, complete with FEM-simulations and experimental measurements, are offered in support of the proposed solutions. Manufacturing issues are dealt with and loss measurement techniques developed as part of this work.

abstract: Three-dimensional (3D) inductors with square, hexagonal and octagonal geometries have been designed and simulated in ANSYS HFSS. The inductors have been designed on Silicon substrate with through-hole via with different width, spacing and thickness. Spice modeling has been done in Agilent ADS and comparison has been made with results of custom excel based calculator and HFSS simulation results. Single ended quality factor was measured as 12.97 and differential ended quality factor was measured as 15.96 at a maximum operational frequency of 3.65GHz. The single ended and differential inductance was measured as 2.98nH and 2.88nH respectively at this frequency. Based on results a symmetric octagonal inductor design has been recommended to be used for application in RF biosensing. A system design has been proposed based on use of this inductor and principle of inductive sensing using magnetic labeling. / Dissertation/Thesis / M.S. Electrical Engineering 2012

In high-frequency circuit design, performance is often limited by the quality of the passive components available for a particular process. Specifically, spiral inductors can be a major bottle-neck for Voltage-Controlled Oscillators (VCOs), Low-Noise Amplifiers (LNAs), mixers, etc. For designers to correctly optimize a circuit using a spiral inductor, several frequency-domain characteristics must be known including the quality factor (Q), total inductance, and the self-resonant frequency. This information can be difficult to predict for spirals built on lossy silicon substrates because of the complicated frequency-dependent loss mechanisms present. The first part of this research addresses the need for a scalable, predictive model for obtaining the frequency domain behavior of spiral inductors on lossy silicon substrates. The technique is based on the Partial Element Equivalent Circuit (PEEC) method and is a flexible approach to modelling spiral inductors. The basic PEEC technique is also enhanced to efficiently include the frequency dependent eddy-currents in the lossy substrate through a new complex-image method. This enhanced PEEC approach includes all of the major non-ideal effects including the conductor-skin and proximity effects, as well as the substrate-skin effect. The approach is applied to octagonal spiral inductors and comparisons with measurements are presented. To complement the scalable enhanced-PEEC model, a new wide-band compact equivalent circuit model is presented which is suitable for time-domain simulations. This model achieves wide-band accuracy through the use of "transformer-loops" to model losses caused by the magnetic field. A fast extraction technique based on a least squares fitting procedure is also described. Results are presented for a transformer-loop compact model extracted from measurements. The combination of an accurate scalable model and a wide-band compact equivalent-circuit model provides a complete modelling methodology for spiral inductors on lossy silicon. / Graduation date: 2003