Chip-Level Thermal Analysis, Modeling, and Optimization Using Multilayer Green's Function.

With the continual scaling of devices and interconnects, accurate analysis and effective optimization of the temperature distribution of a ULSI chip are increasingly important in predicting and ensuring the performance and reliability of the chip before fabrication. Motivated by the design challenges, this dissertation aims at a detailed study of the areas of thermal analysis, modeling, and optimization of ULSI chips. In particular, this dissertation introduces LOTAGre, a high-efficiency O(n lg n) multilayer Green's function-based thermal analysis method. LOTAGre can analyze ULSI chips consisting of multilayer heterogeneous heat conduction materials, with either wire-bonding packaging or flip-chip packaging, under uniform or non-uniform ambient temperatures. By integrating the eigen-expansion technique and the transmission line theory, this dissertation derives the multilayer heat conduction Green's function, including the s-domain version which can be used to compute the thermal transfer impedance between two arbitrary locations in the chip and establish compact thermal models for the critical components in the chip. To aid interconnect thermal analysis, this dissertation introduces a new Schafft-type interconnect temperature distribution model which is very flexible in addressing the effects of chip packaging, surrounding ambient temperatures, and the temperature gradients within the interconnect. An efficient O(n) method is introduced to solve the interconnect temperature distribution from the model. To optimize the chip temperature distribution, this dissertation introduces an optimal power budget model that determines the optimal allocation of cell powers to different regions of the chip so that the resultant temperature distribution most closely approximates the target temperature distribution for the chip. The generalized minimal residue method and the conjugate gradient method are employed to construct top-level and front-level thermal optimizers to solve the optimal power budget efficiently. Finally, the dissertation describes the procedure to incorporate the optimal power budget model into the widely distributed Capo placement tool to enable thermal optimization in the cell placement stage.Ph.D.Computer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/61761/1/baohuaw_1.pd

THERMAL MODELING AND CHARACTERIZATION OF HIGH POWER DEVICES

Ph.DDOCTOR OF PHILOSOPH

The analysis and modeling of fine pitch laminate interconnect in response to large energy fault transients

In embedded applications, the miniaturization of circuitry and functionality provides many benefits to both the producer and consumer. However, the benefits gained from miniaturization is not without penalty, as the environmental influences may be great enough to introduce system failures in new or different modes and effects;Of particular interest within this research is the effect of fault transients in reduced geometries of printed circuit card interconnect, commonly referred to as fine pitch laminate interconnect. Whereas larger geometries of conductor trace width and spacing may have been immune to circuit failure at a given fault input, the reduction of the trace geometry may introduce failures as the insulating effect of the dielectric is compromised to the point where arcing occurs;To address this concern, a circuit card was designed with fine pitch laminate features in microstrip, embedded microstrip, and stripline constructions. Various trace widths and separations were tested for structural integrity (presence of arcing or fusing) at voltage extremes defined in avionics standard. The specific trace widths in the test were 4 mils, 6 mils, 8 mils, and 12 mils, with the trace separation in each case equal to the trace widths. The results of the tests and methods to artificially improve the integrity of the interconnect are documented, providing a clear region of reliable operation to the designers and the engineering community;Finally, the construction of the interconnect and the results from the test were combined to create an empirical model for circuit analysis. Created for the Saber simulator, but readily adaptable to Spice, this model will describe high-speed operation of a propagating signal before breakdown, and uses data from the experiment to calculate threshold values for the arcing breakdown. The values for the breakdown voltages are correlated to the experimental data using statistical methods of weighted linear regression and hypothesis testing

Design of a 2.4 GHz Horizontally Polarized Microstrip Patch Antenna using Rectangular and Circular Directors and Reflectors

In the urban or indoor wireless environment, after a complicated multiple reflection or scattering effect, the polarization of the propagating radio waves may change significantly. Although many current wireless systems are vertically polarized it has been predicted that using horizontally polarized antenna at both the transmitter and receiver has many advantages. In this thesis, new designs are proposed to develop a horizontally polarized microstrip patch antennas for 2.4 GHz applications using directors and reflectors to guide the radiated power. The radiation characteristics of these designs with respect to various geometrical parameters such as the dimensions of the reflector and directors, and spacing between these elements were studied in order to obtain the best possible performance. Also, two-dimensional and three-dimensional radiation patterns, antenna gain and return loss for each of these designs are presented

Electromagnetic Wave Propagation for Industry and Biomedical Applications

This book highlights original research and high-quality technical briefs on electromagnetic wave propagation, radiation, and scattering, and their applications in industry and biomedical engineering. It also presents recent research achievements in the theoretical, computational, and experimental aspects of electromagnetic wave propagation, radiation, and scattering. The book is divided into three sections. Section 1 consists of chapters with general mathematical methods and approaches to the forward and inverse problems of wave propagation. Section 2 presents the problems of wave propagation in superconducting materials and porous media. Finally, Section 3 discusses various industry and biomedical applications of electromagnetic wave propagation, radiation, and scattering

Center for Space Microelectronics Technology

The 1990 technical report of the Jet Propulsion Laboratory Center for Space Microelectronics Technology summarizes the technical accomplishments, publications, presentations, and patents of the center during 1990. The report lists 130 publications, 226 presentations, and 87 new technology reports and patents

Plasmonic control of light emission for enhanced efficiency and beam shaping

Thesis (Ph.D.)--Boston UniversityInGaN alloys and related quantum structures are of great technological importance for the development of visible light emitting devices, motivated by a wide range of applications, particularly solid-state lighting. The InxGa1-xN material system provides continuous emission tuning from the ultraviolet across the visible spectrum by changing the In content. InGaN/GaN quantum wells (QW) also provide an efficient medium for electroluminescence for use as light emitting diodes. It is well known, however, that increasing the In content degrades the internal quantum efficiency of these devices, particularly in the green region of the spectrum. These limitations must be overcome before efficient all-solid-state lighting can be developed beyond the blue-green region using this material system. Recently, the application of plasmonic excitations supported by metallic nanostructures has emerged as a promising approach to address this issue. In this work, metallic nanoparticles (NPs) and nanostructures that support plasmonic modes are engineered to increase the local density of states of the electromagnetic field that overlaps the QW region. This leads to an enhancement of the spontaneous emission rate of the QW region mediated by direct coupling into the plasmonic modes of the nanostructure. Energy stored in these modes can then scatter efficiently into free-space radiation, thereby enhancing the light output intensity. The first section of this thesis concerns the enhancement of InGaN/GaN QW light emission by utilizing localized surface plasmon resonances (LSPRs) and lattice surface modes of metal NP arrays. This work comprises a detailed study of the effect of geometry variations of Ag NPs on the LSPR wavelength, and the subsequent demonstration of photoluminescence intensity enhancement by Ag NPs in the vicinity of InGaN multiple QWs. The second section of this thesis concerns the far-field control of QW emission utilizing metallic nanostructures that support plasmonic excitations. This includes a study of the dispersion and competing effects of a metallic NP-film system, and the demonstration of beam collimation and unidirectional diffraction utilizing a similar geometry. These results may find novel applications in the emerging field of solid-state smart lighting