A new CAD-oriented methodology for the full-wave broadband characterization of coupled microstrip structures for RF/microwave and high-speed digital circuits is presented. The characterization methodology is based on the finite difference time domain (FDTD) technique combined with a systematic extraction procedure using the normal mode approach and multiport network concepts. The...
With increasing operating frequencies in CMOS RF/microwave integrated circuits,
the performance of on-chip interconnects is becoming significantly affected by the lossy
substrate. It is the purpose of the first part of this thesis to develop a rigorous field
theoretic analysis approach for efficient characterization of single and multiple coupled
interconnects...
With increasing transistor operating frequencies, interconnects and passive devices are becoming performance limiters in integrated circuit (IC) designs. To combat this, the interconnect layers above the active silicon are trending toward low-κ dielectrics and Cu metallization. The use of these new materials has popularized chemical mechanical polishing (CMP) to planarize...
Variability in circuit performance due to process defects is a major concern in integrated circuit (IC) fabrication. Advanced IC manufacturing processes employ Chemical-Mechanical Polishing (CMP) for planarization of oxide and metal layers. CMP defects result in variations in the oxide and metal topographical profile. To reduce these topographical variations, electrically...
Magnetically coupled passive transformers are increasingly integrated on-chip for
various analog and radio frequency (RF) applications including direct current
(DC) isolation, impedance transformation/matching, and conversion between
single-ended and differential signals. A primary motivation for the on-chip
integration of transformers is the overall size reduction and reduced cost.
However, the performance...
Passive components, including spiral inductors and transformers, fabricated on silicon-based substrates are placing an increasing demand on radio-frequency integrated circuit (RFIC) design. Performance of the RFIC suffers from several non-ideal effects that must be taken into account in order to create a successful design. In particular, monolithic transformers can be...
Spiral inductors are a key component of mixed-signal and analog integrated circuits (IC's). Such circuits are often fabricated using silicon-based technology, owing to the inherent low-cost and high volume production aspects. However, semiconducting substrate materials such as silicon can have adverse effects on spiral inductor performance due to the lossy...
A novel method for modeling bends in coplanar waveguides (CPWs) is described. The CPW can be viewed as a pair of parallel coupled quasi-slot lines. Bends in the CPW are modeled as a non-uniform coupled line system in terms of their even- and odd- mode characteristics. This modeling approach is...
The addition of thin-film alloy magnetic materials to integrated circuit processing enables a number of novel monolithic circuits. Examples include fully integrated magnetic field sensors, signal and power galvanic isolation circuits, and power supplies on chip (PwrSoC). There are several benefits to integrating these traditionally off-chip devices, including improved manufacturability,...
Emerging fifth generation (5G) and beyond 5G communication networks are stimulating the design of radio-frequency (RF) and millimeter-wave (mmWave) integrated circuits for wireless transceivers systems. While co-integration of active circuits and diverse passive components becomes feasible at these high operating frequencies, circuit design is faced with significant challenges due to...
For mmWave Integrated Circuit (IC) design, co-integration of passives can reduce size and power consumption, increase reliability, and reduce overall cost. However, skin and proximity effects in the metallization are aggravated at mmWave frequencies, resulting in increased attenuation and degradation of overall performance. Furthermore, tight integration of passive components (to...
A versatile computational technique for improved time domain modeling of electromagnetic radiative systems is demonstrated. Two computational methods are combined: the finite-difference time domain (FDTD) method, a full-wave electromagnetic field solver, and the Kirchhoff surface integral formulation, a spatial transformation technique. The combined FDTD/Kirchhoff technique is shown to increase accuracy...
The electrical behavior of on-chip interconnects has become a dominant factor in silicon-based high speed, RF, and mixed-signal integrated circuits. In particular, the frequency-dependent loss mechanisms in heavily-doped silicon substrates can have a large influence on the transmission characteristics of on-chip interconnects. To optimize the performance of the integrated circuit,...
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...
In advanced integrated circuit (IC) processes, the metal fill inserted to meet foundry imposed density requirements degrades the performance of interconnects and passive components which ultimately affects the overall circuit performance. Accounting for this degradation through electromagnetic and equivalent circuit modeling is becoming a critical aspect of IC design. However,...