A complete methodology has been proposed to model and evaluate IC packages in the high-speed digital and radio-frequency applications. The package types that are studied in this dissertation include BGAs, TSSOPs and BCCs. In characterization of BGAs, both frequency-domain and time-domain techniques have been applied and compared to each other. It was found that the best strategy was to find a rough coupled transmission-line model in the time domain and refine it through the optimization scheme in the frequency domain. Equivalent lumped model has been further derived from the coupled transmission-line model using the concept of distributed parameters. For RFIC applications, the electrical model of BCC, one type of lead-frame CSP, has been established based on the frequency-domain technique. To evaluate the package performance, an on-chip 50-ohm microstrip line housed in the package has been investigated. The insertion and return losses were analyzed and measured. Excellent agreement has been observed up to Ku band. The package acts as a low-pass filter to cause a cut off for the line above a certain frequency, which was predicted successfully from the established package model. The simulation results also show that BCC exhibits higher cut-off frequency and lower insertion loss in the passband when compared to TSSOP, one of the currently most popular RFIC packages.

In this research, we used monomer 4,4¡¦¡¦¡¦¡¦-Difluore-3,3¡¦¡¦¡¦¡¦- bis(trifluoromethyl)-2¡¦¡¦,3¡¦¡¦,5¡¦¡¦,6¡¦¡¦-triphenyl and 4,4'-(9-Fluorenylidene) diphenol to fabricate the novel poly(arylene ether)s by the nucleophilic replacement reaction. We call this polymers P-44, and we use Mass and GPC to measure its molecular weight¡FThe molecular structures were investigated and confirmed by NMR and FT-IR. This polymer has high weightaverage molecular weight (Mw) about 5.67¡Ñ104 g/mol. We can realize from the measurement of thermal analysis that its thermal degradation temperature (Td) is 543¢XC, and its glass transition temperature (Tg) is 331¢XC. It shows this polymer: P-44 possesses great thermal stability. Besides, P-44 has not apparent crystallizing point (Tc) so we can adjust that P-44 crystalize hardly. We can know from above that P-44 can not only has good heat tolerance but also has high thermal stability so it can endure futher high tempaerature in the process of fabrication. After interpreting P-44 possesses these well properties, we want to know the properties that P-44 apply to the devices as flexible substrate. So, we fabricate P-44 to be film, and we measure the photoelectrical properties of P-44 film. From this we can observer if P-44 can match the necessary condition that it apply to monitor or high frequency substrate. In the aspect of photophysical properties, we take the 0.3mm P-44 film to measure its photophysical properties. We obtained absorption wavelength that is 245nm and 345nm, and its excitation wavelength is362nm¤Î365nm. Its main area of absorption and excitation is in the region of UV. Furthermore, the transmission spectra of P-44 film showed that visible light transparency were up to 80%. And the refractive index(n) of P-44 film is between 1.37~1.4. In the aspect of thermal mechanical properties, we can know thermal expansion coefficient (CTE) of P-44 film is 19ppm/¢J, and we can also obtain the heat deflection temperature (HDT) of P-44 film is 316¢J. It reveals P-44 possesses low thermal expansion coefficient (CTE) and high heat deflection temperature (HDT). In the aspect of surface, we find P-44 film has low polarity whose main component is van der waals and it has good hydrophobicity.Its contact angle with DI-water is 114.5¢X which greater than 90¢X that proves P-44 film has well hydrophobicity. In the aspect of dielectrical properties, we found that its dielectric constant is between 2.51~2.53 under the condition of1M Hz, and its dielectric loss is between 0.0068~0.0071. It shows P-44 film possesses low dielectric constant that let the effect of parasitic capacitances lowered¡Fand low dielectric loss let the loss of signal reduced. We can plate ITO onto P-44 film successfully, and it could be a flexible transparent conductive film. By the all of the above results, we can realize P-44 film possesses well thermal stabilities¡Bhigh transparency in the region of visible light¡Bgood hydrophobicity¡Blow thermal expansion coefficient (CTE)¡Blow dielectric constant and low dielectric loss. With these great materialIX properties, we can apply it to flexible photpelectric devices in the future.

No description available.

This thesis is focused on the high-frequency performance of carbon nanotube field-effect transistors (CNFETs). Such transistors show their promising performance in the nanoscale regime where quantum mechanics dominates. The short-circuit, common-source, unity-current-gain frequency ft is analyzed through regional signal-delay theory. An energy-dependent effective-mass feature has been added to an existing SP solver and used to compare with results from a constant-effective-mass SP solver. At high drain bias, where electron energies considerably higher than the edge of the first conduction sub-band may be encountered, ft for CNFETs is significantly reduced with respect to predictions using a constant effective mass. The opinion that the band-structure-determined velocity limits the high-frequency performance has been reinforced by performing simulations for p-i-n and n-i-n CNFETs. This necessitated incorporating band-to-band tunneling into the SP solver. Finally, to help put the results from different CNFETs into perspective, a meaningful comparison between CNFETs with doped-contacts and metallic contacts has been made. Band-to-band tunneling, which is a characteristic feature of p-i-n CNFETs, can also occur in n-i-n CNFETs, and it reduces the ft dramatically.

No description available.

This thesis is focused on the high-frequency performance of carbon nanotube field-effect transistors (CNFETs). Such transistors show their promising performance in the nanoscale regime where quantum mechanics dominates. The short-circuit, common-source, unity-current-gain frequency ft is analyzed through regional signal-delay theory. An energy-dependent effective-mass feature has been added to an existing SP solver and used to compare with results from a constant-effective-mass SP solver. At high drain bias, where electron energies considerably higher than the edge of the first conduction sub-band may be encountered, ft for CNFETs is significantly reduced with respect to predictions using a constant effective mass. The opinion that the band-structure-determined velocity limits the high-frequency performance has been reinforced by performing simulations for p-i-n and n-i-n CNFETs. This necessitated incorporating band-to-band tunneling into the SP solver. Finally, to help put the results from different CNFETs into perspective, a meaningful comparison between CNFETs with doped-contacts and metallic contacts has been made. Band-to-band tunneling, which is a characteristic feature of p-i-n CNFETs, can also occur in n-i-n CNFETs, and it reduces the ft dramatically.

Thesis (D.PT.)--Sage Colleges, 2009. / "May 2009." "A Capstone project for PTY 768 presented to the Faculty of the Physical Therapy Department Sage Graduate School in partial fulfillment of the requirements for the degree of Doctor of Physical Therapy." Includes bibliographical references.

An ionospheric topside sounder is a high frequency radar system that is located above the ionosphere, ideally on-board a polar orbiting satellite to provide global coverage. The previous eight satellite sounders have measured the critical frequency of the F2 ionosphere region using traditional swept frequency methods. The most expensive part of these missions however is considered to be the large network of ground support stations required for collecting and processing data. This information has been invaluable in improving our global understanding of the upper ionosphere and the accuracy of critical frequency maps used by HF radio engineers to calculate communications routes and the optimum frequencies for early warning OTH radars. A new technique for the direct detection of critical frequency has been developed, which is called the 'Dispersion Method'. Real data from previous sounders is used in the development and verification of this method. This sounder will not only provide traditional lonograms but detects critical frequency and spread echoes directly from the dispersion of a returning radar pulse. This new method does not use traditional lonograms with their inherent processing complexity and is an order faster than any previous sounder. The 'Dispersion Method' therefore resolves the problems encountered with the past topside sounder missions and produces large quantities of real time data autonomously when required. Previous sounding satellites had little memory capacity, no on-board processing capability, required large antennas and transmitters on satellites with a mass of between 150 and 250 kg. This meant power requirements of about 60 watts per orbit average. A feasibility study to place a third generation topside sounder into low Earth orbit on a 50 kg microsatellite with an orbit average power capacity of only 20 watts has been successfully completed.

Non-contact ignition of TIG welding arcs has been studied. The variation of dc voltage with dc current of combined acdc discharges indicated that an ac-dominated discharge, a dc-dominated discharge and a transition region exist during the initial current rise after breakdown from cold. These measurements enabled the conditions for reliable ignition of dc arcs using a continuous sinusoidal hf source to be predicted. The minimum current to sustain a cold arc and the time taken to reach the steady-state were investigated using a novel capacitor discharge supply. The results showed that to initiate a3 mm TIG welding arc from cold supplied by a power supply with an open circuit voltage of 80 V, a minimum current of about 0.9 A may be required and the time taken for the arc to reach the steady-state may take several hundred milliseconds. The results of investigations on combined ac-dc discharges, minimum current to sustain a cold arc and the time taken to reach the steady-state indicated that for safe, interference-free and reliable non-contact arc ignition, a continuous sinusoidal hf supply was the best method. A high voltage (about 3 kV) and high current (about 1 A) were required simultaneously to initiate a3 mm TIG arc from cold. A single continuous sinusoidal hf supply required an ignition power of the order of 1.35 kW which was not feasible. An arc ignition method using two continuous sinusoidal hf supplies has been devised which provides safe, interference-free and reliable arc ignition, and which requires less than 75% of the output power of a single continuous sinusoidal hf system. A solid-state hf ignition system based on the new method was designed and constructed.

This thesis is focused on the high-frequency performance of carbon nanotube field-effect transistors (CNFETs). Such transistors show their promising performance in the nanoscale regime where quantum mechanics dominates. The short-circuit, common-source, unity-current-gain frequency ft is analyzed through regional signal-delay theory. An energy-dependent effective-mass feature has been added to an existing SP solver and used to compare with results from a constant-effective-mass SP solver. At high drain bias, where electron energies considerably higher than the edge of the first conduction sub-band may be encountered, ft for CNFETs is significantly reduced with respect to predictions using a constant effective mass. The opinion that the band-structure-determined velocity limits the high-frequency performance has been reinforced by performing simulations for p-i-n and n-i-n CNFETs. This necessitated incorporating band-to-band tunneling into the SP solver. Finally, to help put the results from different CNFETs into perspective, a meaningful comparison between CNFETs with doped-contacts and metallic contacts has been made. Band-to-band tunneling, which is a characteristic feature of p-i-n CNFETs, can also occur in n-i-n CNFETs, and it reduces the ft dramatically. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate