Thesis (M.S. in electrical engineering)--Washington State University, December 2009. / Title from PDF title page (viewed on Dec. 28, 2009). "School of Electrical Engineering and Computer Science." Includes bibliographical references (p. 49-51).

This dissertation introduces new technologies and techniques for low-cost phased arrays and scanning antennas. Special emphasis is placed on new approaches for low-cost millimeter-wave beam control. Several topics are covered. A novel reconfigurable grating antenna is presented for low-cost millimeter-wave beam steering. The versatility of the approach is proven by adapting the design to dual-beam and circular-polarized operation. In addition, a simple and accurate procedure is developed for analyzing these antennas. Designs are presented for low-cost microwave/millimeter-wave phased-array transceivers with extremely broad bandwidth. The target applications for these systems are mobile satellite communications and ultra-wideband radar. Monolithic PIN diodes are a useful technology, especially suited for building miniaturized control components in microwave and millimeter-wave phased arrays. This dissertation demonstrates a new strategy for extracting bias-dependent small-signal models for monolithic PIN diodes. The space solar-power satellite (SPS) is a visionary plan that involves beaming electrical power from outer space to the earth using a high-power microwave beam. Such a system must have retrodirective control so that the high-power beam always points on target. This dissertation presents a new phased-array architecture for the SPS system that could considerably reduce its overall cost and complexity. In short, this dissertation presents technologies and techniques that reduce the cost of beam steering at microwave and millimeter-wave frequencies. The results of this work should have a far-ranging impact on the future of wireless systems.

This thesis presents the first fully tunable substrate integrated waveguide (SIW) filter implemented with PIN diodes and RF MEMS switches. The methodology for tuning SIW filters is explained in detail and is used to create three separate designs. Each SIW cavity is tuned by perturbing via posts connecting or disconnecting to/from the cavity's top metal layer. In order to separate the biasing network from the SIW filter, a three-layer PCB is fabricated using Rogers RT/duroid substrates. The first tunable design utilizes the Philips BAP55L PIN diode. This two-pole filter provides six frequency states ranging from 1.55 GHz to 2.0 GHz. Fractional bandwidth ranges from 2.3 percent – 3.0 percent with insertion loss and return loss better than 5.4 dB and 14 dB respectively for all frequency tuning states. The second tunable design utilizes the Radant RMSW-100 MEMS switch, providing six states ranging from 1.65 GHz to 2.1 GHz. Fractional bandwidth for this filter varies from 2.5 percent - 3.0 percent with insertion loss and return loss better than 12.4 dB and 16 dB respectively for all states. The third design utilizes the OMRON 2SMES-01 RF MEMS relay, providing fourteen states ranging from 1.19 GHz to 1.58 GHz. Fractional bandwidth ranges from 3.6 percent - 4.4 percent with insertion loss and return loss better than 4.1 dB and 15 dB respectively for all frequency states. Two of the three designs (Philips PIN diode and OMRON MEMS) produced good results validating the new SIW filter tuning methodology. Finally, to illustrate the advantage of microstrip planar structures integrated with SIW structures, low pass filters (LPFs) are implemented along the input and output microstrip-to-SIW transition regions of the tunable SIW filter. With minimal change to the overall filter size, this provides spurious suppression for the additional resonant modes inherently present in waveguide structures. The implemented design utilizes the same OMRON MEMS tunable SIW filter specifications. This two-pole tunable filter provides the same performance as the previous OMRON MEMS design with exception to an added 0.7 dB insertion loss and spurious suppression of -28 dB up to 4.0 GHz for all frequency tuning states.

This dissertation introduces new technologies and techniques for low-cost phased arrays and scanning antennas. Special emphasis is placed on new approaches for low-cost millimeter-wave beam control. Several topics are covered. A novel reconfigurable grating antenna is presented for low-cost millimeter-wave beam steering. The versatility of the approach is proven by adapting the design to dual-beam and circular-polarized operation. In addition, a simple and accurate procedure is developed for analyzing these antennas. Designs are presented for low-cost microwave/millimeter-wave phased-array transceivers with extremely broad bandwidth. The target applications for these systems are mobile satellite communications and ultra-wideband radar. Monolithic PIN diodes are a useful technology, especially suited for building miniaturized control components in microwave and millimeter-wave phased arrays. This dissertation demonstrates a new strategy for extracting bias-dependent small-signal models for monolithic PIN diodes. The space solar-power satellite (SPS) is a visionary plan that involves beaming electrical power from outer space to the earth using a high-power microwave beam. Such a system must have retrodirective control so that the high-power beam always points on target. This dissertation presents a new phased-array architecture for the SPS system that could considerably reduce its overall cost and complexity. In short, this dissertation presents technologies and techniques that reduce the cost of beam steering at microwave and millimeter-wave frequencies. The results of this work should have a far-ranging impact on the future of wireless systems.

Superior properties of Silicon Carbide (SiC), such as wide bandgap, high breakdown field and high thermal conductivity, have made it the frontrunner to replace Silicon for applications requiring high breakdown strength, mechanical and radiation hardness. Commercial SiC devices are already available, although their expected performance has not yet been realized due to a few problems related to device fabrication technologies, such as selective doping. This work explores non-traditional techniques for SiC doping (and selective doping in particular) based on previously unknown types of defect reactions in SiC and novel epitaxial growth techniques, which offer advantages over currently available technologies. Recent developments in SiC epitaxial growth techniques at MSU have enabled the growth of high quality SiC epitaxial layers at record low temperatures of 1,300°C. Lower growth temperatures have enabled highly doped epilayers for device applications. Prototypes of SiC PiN diodes fabricated, demonstrated low values of the series resistance associated with anodes grown by the low temperature epitaxial growth technique. At room temperature, 100 ìm-diameter diodes with a forward voltage of 3.75 V and 3.23V at 1,000 A/cm2 before and after annealing were achieved. The reverse breakdown voltage was more than 680 V on average, even without surface passivation or edge termination. Reduced growth temperatures also enabled the possibility of selective epitaxial growth (SEG) of SiC with traditional masks used in the SEG in Si technology. Previously, SEG of SiC was impossible without high temperature masks. Good quality, defect free, selectively grown 4H-SiC epilayers were obtained using SiO2 mask. Nitrogen doped selectively grown epilayers were also obtained, which were almost completely ohmic, indicating doping exceeding 1x1019 cm-3. Moreover, conductivity modulation via defect reactions in SiC has been reported as a part of this work for the first time. The approach is based on a new phenomenon in SiC, named Recombination Induced Passivation (RIP), which was observed when hydrogenated SiC epilayers were subjected to above bandgap optical excitation. Additional acceptor passivation, and thereby modification of the conductivity of the epilayer, was observed. Results of investigations of the RIP process are presented, and conductivity modulation techniques based on the RIP process are proposed.

Moore's Law influences more than just the speed of the latest microprocessor. The law drives many facets of the semiconductor realm. As Moore's Law continues to prevail, switching frequencies for electronics will rise. These increased switching frequencies will cause transient losses to be augmented, especially for power electronics. However, there has been a lack of work on how to improve the most simple semiconductor power device, the PiN diode. Therefore, considerable effort has been made to reduce switching losses in modern power semiconductor devices. Power diodes are used as a building block for almost all power electronics, especially boost converters for power factor correction. The re5earch presented in this thesis demonstrates that switching losses will be reduced when a power diode is replaced by two lower voltage diodes arranged in series. One such company, Q-speed, is already implementing such a technique [l]. The company is using two fast recovery diodes on one integrated circuit. Q-speed's results were comparable to more expensive methods to reduce switching losses such as the use of exotic materials like silicon-carbide. There have been many models to date for the PiN diode, but no research ha5 been published about this innovative idea. Research gathered in this thesis from extensive TCAD simulations and experiments will enlighten the power semiconductor field to this interesting approach.

Thesis (PhD (Electric and Electronic Engineering))--University of Stellenbosch, 2005. / A tunable X-band PIN diode switch, implemented in evanescent mode waveguide, is presented. To allow in-situ tuning of resonances after construction, a novel PIN diode mounting structure is proposed and verified, offering substantial advantages in assembly costs. Accurate and time-effective modelling of filter and limiter states of the proposed switch is possible, using an evanescent mode PIN diode and mount model. The model is developed by optimizing an AWR Microwave Office model of a first order switch prototype with embedded PIN diode, to simultaneously fit filter and limiter measurements of four first order prototypes. The model is then used in the design of a third order switch prototype, achieving isolation of 62 dB over a 8.5 to 10.5 GHz bandwidth in the limiting state, as well as reflection of 15.73 dB and insertion loss of 1.23±0.155 dB in the filtering state over the same bandwidth.

Le travail réalisé lors de cette thèse s’inscrit dans le projet de création d’un calorimètre électromagnétique pour le futur International Linear Collider (ILC) au sein de la collaboration CALICE. Le calorimètre est dit ultra-granulaire du fait du grand nombre de pixels de détection : environ 82 millions dans le calorimètre final complet. C’est ce nombre élevé de détecteurs à lire qui a conduit au développement de circuits intégrés dédiés à cette tâche, l’usage d’électronique classique n’étant pas possible dans ce cas du fait de contraintes dimensionnelles. Les travaux démarrent par l’étude de la puce SKIROC2, développée par le laboratoire Omega, qui est l’état de l’art de l’ASIC de lecture pour ce projet. Les performances sur carte de test et dans l’environnement du détecteur ont été mesurées, ce qui a permis de tirer certaines conclusions sur les forces et les faiblesses de SKIROC2. Après cette étude, le travail a été le développement d’un nouvel ASIC de lecture se basant sur SKIROC2. L’objectif étant de préserver les forces de SKIROC2 tout en tentant d’en corriger les faiblesses. Le nouvel ASIC a été conçu dans une technologie tout juste disponible au moment de la conception. Il a donc tout fallu redessiner en repartant de zéro. Il s’agit en cela de building blocks plus que d’un véritable ASIC de lecture. Trois structures de préamplificateurs de charge ont été testées, l’architecture générale et le fonctionnement d’un canal de lecture étant largement inspirés de SKIROC2. / This work takes place in the design project of the electromagnetic calorimeter for the future International Linear Collider (ILC) within the CALICE collaboration. The final calorimeter will be made of 82 million of PIN diodes; this is where the term “high granularity” comes from. The need for a read-out ASIC is a consequence of this high number of detectors, knowing that the dimensions of the electromagnetic calorimeter are a big constraint: the standard electronics is not an option. This work starts from an existing ASIC called SKIROC2. This state-of-the-art read-out chip has been designed by the Omega laboratory, a member of the CALICE collaboration. The performances on testboard and in the detector environment have been measured. It allowed to conclude on the advantages and drawbacks of using SKIROC2 in the calorimeter. After that the focus has been made on the design of a new read-out chip based on SKIROC2. The main goal was to preserve the good performances of SKIROC2 while trying to correct the encountered issues. This new ASIC has been developped in a newly released technology available during the design phase. Therefore the design has been started from scratch. The final chip is composed of building blocks rather than a ready-to-use read-out chip. Three charge preamplifier designs have been tested, the general architecture of a read-out channel being largely inspired by SKIROC2.

Aukštųjų energijų fizikos eksperimentuose plačiai taikomi puslaidininkiniai pin struktūros dalelių detektoriai jonizuojančiosioms dalelėms registruoti. Radiacinė spinduliuotė sukuria defektus medžiagoje ir neigiamai įtakoja detektorių parametrus, todėl būtina charakterizuoti apšvitintus detektorius ieškant būdų, kaip juos patobulinti. Apšvitintų detektorių charakterizavimui taikomi volt-amperinių, volt-faradinių būdingųjų dydžių matavimai ir analizė, giliųjų lygmenų talpinė bei šiluma skatinamų srovių spektroskopija. Tačiau stipriai apšvitintuose detektoriuose, kai defektų koncentracija viršija legirantų koncentraciją bei išauga nuotėkio srovė, šie metodai negali būti taikomi siekiant korektiškai įvertinti radiacinių defektų parametrus. Šiame darbe buvo sukurti modeliai, apibūdinantys slinkties sroves, tekančias detektoriuje dėl elektrinio lauko persiskirstymo keičiantis išorinei įtampai arba elektriniame lauke judant injektuotam krūviui. Šie modeliai buvo pritaikyti naujų metodikų sukūrimui, kurios įgalina įvertinti krūvio pernašos, pagavimo, rekombinacijos/generacijos parametrus stipriai apšvitintuose detektoriuose po apšvitos. Sukurti metodai buvo pritaikyti defektų spektroskopijai ir skersinei žvalgai sluoksninėse struktūrose bei defektų evoliucijos tyrimams apšvitos metu. Disertacijoje pateikti ir aptarti apšvitintų detektorių ir apšvitos metu pasireiškiančios parametrų kaitos rezultatai. Elektronikos grandynuose plačiai naudojami galios pin struktūros diodai, kurie... [toliau žr. visą tekstą] / In high energy physics experiments the semiconductor particle detectors of pin structure are commonly employed for tracking of the ionising particles. However, ionising radiation creates defects and consequently affects the parameters of particle detectors. Therefore, it is necessary to characterize irradiated detectors and search for the new approaches on how to suppress or control the degradation process. Measurements of current-voltage, capacitance-voltage characteristics as well as deep level transient spectroscopy, thermally stimulated currents spectroscopy are employed for the characterization of irradiated particle detectors. At high irradiation fluences when defects concentration exceeds that of dopants, a generation current increases and, thus, the above mentioned techniques can not be applied for the correct evaluation of defect parameters. In this work, models describing displacement currents in detectors due to redistribution of electric field determined by variations of external voltage or a moving charge in electric field are discussed. These models were applied for creation of the advanced techniques which allow evaluating of charge transport, trapping and recombination/generation parameters in heavily irradiated detectors after irradiation. These techniques were applied for the spectroscopy of deep levels associated with defects, for cross-sectional scans within layered junction structures as well as for examination of defects evolution during irradiation. In... [to full text]

In high energy physics experiments the semiconductor particle detectors of pin structure are commonly employed for tracking of the ionising particles. However, ionising radiation creates defects and consequently affects the parameters of particle detectors. Therefore, it is necessary to characterize irradiated detectors and search for the new approaches on how to suppress or control the degradation process. Measurements of current-voltage, capacitance-voltage characteristics as well as deep level transient spectroscopy, thermally stimulated currents spectroscopy are employed for the characterization of irradiated particle detectors. At high irradiation fluences when defects concentration exceeds that of dopants, a generation current increases and, thus, the above mentioned techniques can not be applied for the correct evaluation of defect parameters. In this work, models describing displacement currents in detectors due to redistribution of electric field determined by variations of external voltage or a moving charge in electric field are discussed. These models were applied for creation of the advanced techniques which allow evaluating of charge transport, trapping and recombination/generation parameters in heavily irradiated detectors after irradiation. These techniques were applied for the spectroscopy of deep levels associated with defects, for cross-sectional scans within layered junction structures as well as for examination of defects evolution during irradiation. In... [to full text] / Aukštųjų energijų fizikos eksperimentuose plačiai taikomi puslaidininkiniai pin struktūros dalelių detektoriai jonizuojančiosioms dalelėms registruoti. Radiacinė spinduliuotė sukuria defektus medžiagoje ir neigiamai įtakoja detektorių parametrus, todėl būtina charakterizuoti apšvitintus detektorius ieškant būdų, kaip juos patobulinti. Apšvitintų detektorių charakterizavimui taikomi volt-amperinių, volt-faradinių būdingųjų dydžių matavimai ir analizė, giliųjų lygmenų talpinė bei šiluma skatinamų srovių spektroskopija. Tačiau stipriai apšvitintuose detektoriuose, kai defektų koncentracija viršija legirantų koncentraciją bei išauga nuotėkio srovė, šie metodai negali būti taikomi siekiant korektiškai įvertinti radiacinių defektų parametrus. Šiame darbe buvo sukurti modeliai, apibūdinantys slinkties sroves, tekančias detektoriuje dėl elektrinio lauko persiskirstymo keičiantis išorinei įtampai arba elektriniame lauke judant injektuotam krūviui. Šie modeliai buvo pritaikyti naujų metodikų sukūrimui, kurios įgalina įvertinti krūvio pernašos, pagavimo, rekombinacijos/generacijos parametrus stipriai apšvitintuose detektoriuose po apšvitos. Sukurti metodai buvo pritaikyti defektų spektroskopijai ir skersinei žvalgai sluoksninėse struktūrose bei defektų evoliucijos tyrimams apšvitos metu. Disertacijoje pateikti ir aptarti apšvitintų detektorių ir apšvitos metu pasireiškiančios parametrų kaitos rezultatai. Elektronikos grandynuose plačiai naudojami galios pin struktūros diodai, kurie... [toliau žr. visą tekstą]