Passive and active circuits in cmos technology for rf, microwave and millimeter wave applications

The permeation of CMOS technology to radio frequencies and beyond has fuelled an urgent need for a diverse array of passive and active circuits that address the challenges of rapidly emerging wireless applications. While traditional analog based design approaches satisfy some applications, the stringent requirements of newly emerging applications cannot necessarily be addressed by existing design ideas and compel designers to pursue alternatives. One such alternative, an amalgamation of microwave and analog design techniques, is pursued in this work. A number of passive and active circuits have been designed using a combination of microwave and analog design techniques. For passives, the most crucial challenge to their CMOS implementation is identified as their large dimensions that are not compatible with CMOS technology. To address this issue, several design techniques – including multi-layered design and slow wave structures – are proposed and demonstrated through experimental results after being suitably tailored for CMOS technology. A number of novel passive structures - including a compact 10 GHz hairpin resonator, a broadband, low loss 25-35 GHz Lange coupler, a 25-35 GHz thin film microstrip (TFMS) ring hybrid, an array of 0.8 nH and 0.4 nH multi-layered high self resonant frequency (SRF) inductors are proposed, designed and experimentally verified. A number of active circuits are also designed and notable experimental results are presented. These include 3-10 GHz and DC-20 GHz distributed low noise amplifiers (LNA), a dual wideband Low noise amplifier and 15 GHz distributed voltage controlled oscillators (DVCO). Distributed amplifiers are identified as particularly effective in the development of wideband receiver front end sub-systems due to their gain flatness, excellent matching and high linearity. The most important challenge to the implementation of distributed amplifiers in CMOS RFICs is identified as the issue of their miniaturization. This problem is solved by using integrated multi-layered inductors instead of transmission lines to achieve over 90% size compression compared to earlier CMOS implementations. Finally, a dual wideband receiver front end sub-system is designed employing the miniaturized distributed amplifier with resonant loads and integrated with a double balanced Gilbert cell mixer to perform dual band operation. The receiver front end measured results show 15 dB conversion gain, and a 1-dB compression point of -4.1 dBm in the centre of band 1 (from 3.1 to 5.0 GHz) and -5.2 dBm in the centre of band 2 (from 5.8 to 8 GHz) with input return loss less than 10 dB throughout the two bands of operation

Physical Aspects of VLSI Design with a Focus on Three-Dimensional Integrated Circuit Applications

This work is on three-dimensional integration (3DI), and physical problems and aspects of VLSI design. Miniaturization and highly complex integrated systems in microelectronics have led to the 3DI development as a promising technological approach. 3DI offers numerous advantages: Size, power consumption, hybrid integration etc., with more thermal problems and physical complexity as trade-offs. We open this work by presenting the design and testing of an example 3DI system, to our knowledge the first self-powering system in a three-dimensional SOI technology. The system uses ambient optical energy harvested by a photodiode array and stored in an integrated capacitor. An on-chip metal interconnect network, beyond its designed role, behaves as a parasitic load vulnerable to electromagnetic coupling. We have developed a spatially-dependent, transient Green's Function based method of calculating the response of an interconnect network to noise. This efficient method can model network delays and noise sensitivity, which are involved problems in both planar and especially in 3DICs. Three-dimensional systems are more susceptible to thermal problems, which also affect VLSI with high power densities, of complex systems and under extreme temperatures. We analytically and experimentally investigate thermal effects in ICs. We study the effects of non-uniform, non-isotropic thermal conductivity of the typically complex IC material system, with a simulator we developed including this complexity. Through our simulations, verified by experiments, we propose a method of cooling or directionally heating IC regions. 3DICs are suited for developing wireless sensor networks, commonly referred to as ``smart dust.'' The ideal smart dust node includes RF communication circuits with on-chip passive components. We present an experimental study of on-chip inductors and transformers as integrated passives. We also demonstrate the performance improvement in 3DI with its lower capacitive loads. 3DI technology is just one example of the intense development in today's electronics, which maintains the need for educational methods to assist student recruitment into technology, to prepare students for a demanding technological landscape, and to raise societal awareness of technology. We conclude this work by presenting three electrical engineering curricula we designed and implemented, targeting these needs among others

Instrumentation for the Control of Biological Function through Electrical Stimulation

Electrical signals play a vital role in the makeup and processing of biological systems. While crucial for desired biological functions, they are also directly involved in degenerative and undesirable activity in these systems. Controlling biological function through targeted electrical stimulation is possible in both non-excitable cells and excitable cells. For each cell type, instrumentation for one specific application is covered in the following. Firstly, this thesis studies electrical stimulation setups and instrumentation for the enhancement of transgene expression in gene therapy. Although the applications of this work are manifold, the focus here is on improving wound healing and tissue regeneration, which is especially important in the treatment of non-closing wounds. Specifically, the ability of iontophoresis to enhance transgene expression in dermal and epidermal cells is assessed. For this, an electrical stimulation circuit with electrodes is developed and employed in in vivo experiments. The genes, in the form of charged DNA plasmids, are injected subcutaneously at the wound border of an adult rat model. An electrical field is applied to the tissue via the electrodes, which forces the plasmids onto a trajectory and forms pores in the cell's membranes to enhance transfection. Various stimulation parameters and setups, as well as different luciferase encoding plasmids, are tested to determine the optimal experimental setup for transgene expression. Secondly, this thesis studies neural implants for the excitation and inhibition of neurons. Neural implants are vital in the treatment of neurological diseases, and allow us to better understand how the brain processes information. The brain is a complex organ which is known to function by its multiple parts working together. Wireless sub-millimeter implants placed individually throughout the brain can imitate natural spatio-temporal stimulation patterns, while causing only minimal tissue destruction. In this thesis, the design of such an implant is elucidated in its entirety, with special focus on the wireless power link. Power from an external primary inductor will inductively be transferred to a secondary inductor that is implanted in the brain. The design trade-offs in selecting the geometry and configuration of the inductors are described and the analysis, simulation, and testing results are presented with the suggestion of an optimal design

Design, manufacturing and characterisation of a wireless flexible pressure sensor system for the monitoring of the gastro-intestinal tract

Ingestible motility capsule (IMC) endoscopy holds a strong potential in providing advanced diagnostic capabilities within the small intestine with higher patient tolerance for pathologies such as irritable bowel syndrome, gastroparesis and chronic abdominal amongst others. Currently state-of-the art IMCs are limited by the use of obstructive off-the-shelf sensing modules that are unable to provide multi-site tactile monitoring of the Gastro-Intestinal tract. In this work a novel 12 mm in diameter by 30 mm in length IMC is presented that utilises custom-built flexible, thin-film, biocompatible, wireless and highly sensitive tactile pressure sensors arrays functionalising the capsule shell. The 150 μm thick, microstructured, PDMS flexible passive pressure sensors are wirelessly powered and interrogated, and are capable of detecting pressure values ranging from 0.1 kPa up to 30 kPa with a 0.1 kPa resolution. A novel bottom-up wafer-scale microfabrication process is presented which enables the development of these ultra-dense, self-aligned, scalable and uniquely addressable flexible wireless sensors with high yield (>80%). This thesis also presents an innovative metallisation microfabrication process on soft-elastomeric substrates capable to withstand without failure of the tracks 180o bending, folding and iterative deformation such as to allow conformable mapping of these sensors. A custom-built and low-cost reflectometer system was also designed, built and tested within the capsule that can provide a fast (100 ms) and accurate extraction (±0.1 kPa) of their response. In vitro and in vivo characterisation of the developed IMC device is also presented, facilitated respectively via the use of a biomimetic phantom gut and via live porcine subjects. The capsule device was found to successfully capture respiration, low-amplitude and peristaltic motility of the GI tract from multiple sites of the capsule.UK Engineering & Physical Sciences Research Council (EPSRC) through the Programme Grant Sonopill (EP/K034537/2)James Watt Scholarshi

Modelagem de transformadores em circuitos integrados utilizando tecnologia CMOS na faixa de 1 a 10 GHz

Orientador: Prof. Dr. Bernardo LeiteTese (doutorado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Elétrica. Defesa : Curitiba, 15/05/2023Inclui referênciasResumo: Este trabalho define um modelo elétrico, com parâmetros concentrados, equivalente a transformadores coplanares em circuitos integrados na tecnologia CMOS com plano de blindagem, para a faixa de 1 a 10 GHz. Este modelo é obtido a partir de otimização e a partir das características físicas deste transformador. O modelo elétrico equivalente é comparado com o transformador simulado com o método de elementos finitos (FEM) considerando as suas indutâncias, resistências e o acoplamento entre enrolamentos. O resultado de associação série somativa e subtrativa, além de seu comportamento em um oscilador controlado por tensão também são comparados com o transformador simulado. Adicionalmente um método para o cálculo do acoplamento magnético, baseado em áreas equivalentes é proposto. O erro máximo (dos parâmetros S) entre o modelo elétrico equivalente e o transformador simulado ficaram menores que 6 % para os circuitos otimizados e 8 % para os circuitos calculados, tornando seu uso possível em projeto de circuitos de radiofrequência nesta faixa de frequência e para esta tecnologia.Abstract: The main goal of this work is to define an electrical model, with lumped parameters, equivalent to coplanar transformers to be used in CMOS integrated circuits, to operate between 1 GHz and 10 GHz, using a shield plane. This model is obtained from optimization and from the physical characteristics of this transformer. The equivalent electrical model is compared with the transformer simulated using the finite element considering its inductances, resistances and coupling between windings. The result of summative and subtractive series association, in addition to its behavior in a voltage-controlled oscillator are also compared with the simulated transformer. Additionally, a method for calculating the magnetic coupling based on equivalent areas is proposed. The maximum error (S parameters) between the equivalent electrical model and the simulated transformer was less than 6% for the optimized circuits and 8% for the calculated circuits, making its use possible in the design of radiofrequency circuits in this frequency range and for this technology

Macro-meso-microsystems integration in LTCC : LDRD report.

Low Temperature Cofired Ceramic (LTCC) has proven to be an enabling medium for microsystem technologies, because of its desirable electrical, physical, and chemical properties coupled with its capability for rapid prototyping and scalable manufacturing of components. LTCC is viewed as an extension of hybrid microcircuits, and in that function it enables development, testing, and deployment of silicon microsystems. However, its versatility has allowed it to succeed as a microsystem medium in its own right, with applications in non-microelectronic meso-scale devices and in a range of sensor devices. Applications include silicon microfluidic ''chip-and-wire'' systems and fluid grid array (FGA)/microfluidic multichip modules using embedded channels in LTCC, and cofired electro-mechanical systems with moving parts. Both the microfluidic and mechanical system applications are enabled by sacrificial volume materials (SVM), which serve to create and maintain cavities and separation gaps during the lamination and cofiring process. SVMs consisting of thermally fugitive or partially inert materials are easily incorporated. Recognizing the premium on devices that are cofired rather than assembled, we report on functional-as-released and functional-as-fired moving parts. Additional applications for cofired transparent windows, some as small as an optical fiber, are also described. The applications described help pave the way for widespread application of LTCC to biomedical, control, analysis, characterization, and radio frequency (RF) functions for macro-meso-microsystems

An Implantable Microsystem for Autonomous Intraocular Pressure Monitoring .

Glaucoma, a leading cause of blindness worldwide, is a disease in which the pressure within the eye is too high for the eye to tolerate and must be reduced in order to slow or prevent damage to the optic nerve. Conventional methods for monitoring eye pressure are normally only used in the physician’s office and rely on indirect measurement methods, leading to inaccuracies. Furthermore, intraocular pressure can vary throughout the day and also depends on activity. An autonomous implantable microsystem capable of monitoring intraocular pressure with minimal patient intervention would provide useful information to the clinician in the management of glaucoma. This dissertation studies the feasibility of an integrated microsystem for autonomously measuring intraocular pressure. Small size ensures minimal impact on the patient, preventing the device from entering the field of view and simplifying implantation. Integrated haptics aid surgical implantation and minimize trauma while allowing the implant to be removed if needed. A touch-mode capacitive pressure sensor, fabricated using the dissolved wafer process, transduces intraocular pressure into capacitance with a linear response and a sensitivity of 26 fF/mmHg. A new fabrication technique has been developed to embed vertical interconnects within a glass package containing the pressure sensor, a microbattery, readout circuitry, and an antenna. This enables the vertical stacking of these components and very efficient use of limited volume. The 1.5 mm x 2 mm x 0.5 mm transparent parylene-coated glass package enables solar cells to be placed on the circuit chip for power generation, trickle charging an on-board microbattery formed using standard cleanroom materials and a non-toxic electrolyte. Flooded-cell tests verified the electrochemistry and achieved a current capacity of 8 µAh/mm2. A simple integrated readout circuit consuming 35 pW in the idle mode implemented a finite-state machine and used an optical wakeup trigger to further reduce power. The microsystem has also been demonstrated with a microprocessor to autonomously gather and store data, reading it out on demand. Finally, a pulse-based ultrawideband wireless transmission technique is proposed using non-resonant antennas. The all-digital transmitter is expected to consume much less power than conventional encoded wireless transmitters and eliminates complex circuitry.Ph.D.Electrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/89809/1/rhaque_1.pd