Apart from being a support, the three substrates had their own roles in the growth of CNTs. Bamboo charcoal also acted as a catalyst provider. Au-coated silicon wafer participated in the formation of the silica/CNT composite nanowires. Copper foil itself was a catalyst. The silicate, the Au/Si droplet, and the copper particles were the catalysts for the growth of CNTs in these three substrates, respectively. The formation of the CNTs followed the vapor-liquid-solid (VLS) route which involved the decomposition of ethanol vapor into carbon, carbon dissolution inside the liquid catalyst and precipitation to form CNTs. / CNTs could be grown in a very wide temperature range (700-1400°C), but specific substrate for a particular temperature range was needed. The structures of the CNTs varied with the CVD processing conditions. The forms and the amount of catalytic material entering the interior of the CNTs depended on the characteristics of the catalyst for that process / The products formed on different substrates had their own characteristic features . Hollow or silicate filled CNTs with silicate droplet tips were formed on the surface of bamboo charcoal. Their diameter was in hundreds of nanometers and the length was about several microns. CNT-coated silica core-shell structures were obtained on Au-coated silicon wafer. The graphitic carbon shell was formed in thickness about 145 nm for the sample prepared at 1185°C, but amorphous carbon shell was produced in thickness more than 300 nm for the sample prepared at 1236°e. Lastly, CNTs with bamboo-like structure were synthesized on the copper foil substrate. The CNTs were getting thicker from 70 nm to 170 nm when temperature was increased from 700°C to 1000°C. The yield increased with temperature and annealing time if the sample was annealed for less than 30 min. / We report the growth of carbon nanotubes (CNTs) on different types of substrates with or without catalytic materials by using different approaches. The roles of the substrates and the catalysts in the formation of the CNTs are studied . We also characterized and identified the structural properties of the CNTs products. In this work, three types of substrates had been used, namely biomorphic bamboo charcoal , Au-coated silicon wafer, and copper foil. The CNTs were grown on different substrates by chemical vapor deposition (CVD) method at temperature range between 700°C and 1400°C. Ethanol vapor was used as the carbon source, while tetraethyl orthosilicate (TEOS) vapor was also applied to the process for bamboo charcoal. / Zhu, Jiangtao = 碳納米管在不同類型基底上的生長 / 朱江濤. / Adviser: D. H. L. Ng. / Source: Dissertation Abstracts International, Volume: 72-11, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Zhu, Jiangtao = Tan na mi guan zai bu tong lei xing ji di shang de sheng chang / Zhu Jiangtao.

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Abstract Electrodeposited Copper Foil (ED Foil) is the most essential conductive material to PCB. With the recession of electronic industry and the appearance of Internet Economy Bubble for printed circuit board (PCB) industry, PCB industry slowed down its productivity around 2000 and the ED Foil industry in Taiwan had to face the vicious circle as the supply exceeds the demand. As for America, because of the declination of the industry, it is now almost out of the ED Foil industry which means that the global chief city of the field has changed from the States to Japan. However, with the high production costs and labor expenses, Japan is now suspending the enlargement of productivity, Therefore, the productivity of Taiwan till 2005 already ranked the top one in the world. Unfortunately, we are now facing the biggest competitor, China, who has tried enthusiastically to attract our ED Foil and PCB companies to move to his land, especially it has aimed the ED Foil industry as his top target to enkindle. This research has consulted several diverse documents from inside and outside Taiwan through the analyses of industrial structures, ¡§Diamond System¡¨ and ¡§SWOT Analysis¡¨ to have a clear understanding towards the construction of Taiwan¡¦s ED Foil industry and its ¡§competitive advantages¡¨. Owning these accomplished advantages as the base, we can come out the cooperative strategies for ED Foil industry¡¦s future and its ¡§Anti Competition Policy¡¨ according to the ¡§scenarios¡¨. We deeply hope that with these devices, we can strengthen the industrial¡¦s efficiency in our ED Foil¡¦s industry and at the same time, our status in this field can remain competitive around the world. The research found out that in ED Foil industry¡¦s area, the early players monopolized the market and twisted the market¡¦s efficiency at the same time. Therefore, those early players got the chance to earn a huge sum of money and as a result, some potential competitors joined the market to share the benefits. Besides, because of the rising concept of globalization among the mega electronic companies, more and more module and component companies are willing to be localized to correspond to the change. Simultaneously, the demand of both PCB and ED Foil has started to increase in Asia; therefore, the ED Foil industry in Taiwan is getting more and more prosperous because of the favorable geographical position. Moreover, high performing and large-sized facilities are adapted to produce high quality and low cost merchandizes efficiently to enhance the competitiveness in the industry. Therefore, the chain that connected with the downstream industry has become more completed and moreover, the bunching effect can be elaborate thoroughly. According to the research, we have discovered that there are many uncertainties within the operation of Taiwan¡¦s ED Foil industry such as the slight increase of the demand in Taiwan and the exports are overly centered on Hong Kong and China. Other concern like the percentage of the fixed prime cost is excessively high matters the efficiency of the productivity and as a result, a price war comes out easily because of the supply exceeds the demand. In the meantime, we have come out with the conclusion that the government should actively help the integration of the industry¡¦s future development. And we suggest that the ED Foil industry in Taiwan should take the co-opetition policy as follows: 1. The buying-associations that share the supplementary values of the recycling copper wires and R&D-associations can share the R&D cost in the area of the newly applying development will be erected to largely reduce the prime costs. Furthermore, an information exchange center will be provided for those associations to utilize others¡¦ useful experiences. 2. The business cooperative operations either with the same upstream or downstream companies all necessarily needed to be constructed. Those united cooperation such as Mergers & Acquisitions should be promoted within industries, including investments. These strategies will accelerate the development of the business. 3. New and prosperous markets such as Thailand and Vietnam need to be explored to disperse our export markets to decrease our dependency on China. 4. Complementary relationship and proper division of labors should be built up within cross-Strait without making other vicious competitions.

This research has discussed the graphene growth mechanism and the achievement, the main purpose is to try the best method to grow graphene which is large size, uniform, and continue. The main issue is about growth and characterizations in full text which is separated by thermal annealing 6-H SiC(001) and chemical vapor deposition on the copper foil to grow graphenen. For instances, to adjust the growth parameters and the growth methods to get graphene and to control the quality, to analysis the number of layers, to research the characterizations during growth process, and to find the better transfer method are all the important focus in this paper. The morphology of samples is studied by SEM, AFM, STM, OM and so on, further the thickness of graphene layers can be observed by AFM and STM. Due to the limit of instruments, the thickness of graphene layer (~0.35 nm) and the thickness of 6-H SiC(001) steps (~1.5 nm) are not easy to observe actually. Raman spectroscopy is the main analysis tool I have employed, it is the fast way to calculate the number of layers (G, 2D band). In addition, Raman scattering is able to know the information of electronic structure variation (2D band), to investigate the stress which is caused by substrate and to estimate the quality of graphene (D, G band). Finally, I take chemical vapor deposition to grow graphenen on the copper foil. Sample is successfully transferred onto SiO2, and the number of graphene layers is estimated to be about two and the structure is AA stacking from these data. The data also shows the graphene is large size, uniform, and continue.

Pb(Zr₀.₅₂Ti₀.₄₈)O₃ (PZT) thin films are of interest for their large dielectric permittivity, ferroelectric, and piezoelectric properties. The material has been widely studied for use in high frequency transducers, multi-layered capacitors, and ferroelectric random access memory. Copper foils are an inexpensive, flexible substrate with a low resistivity which makes them ideal for many transducer and capacitor applications. PZT thin films on copper foils were produced by RF sputtering and crystallized under reducing conditions. Causes and prevention of a cuprous oxide interlayer are discussed. The film structure was characterized by XRD, SEM, and AFM. The permittivity was low, but remanent polarization increased to as high as ~40 μC/cm² as film thickness and crystallization temperature increased. Residual stresses were measured by x-ray diffraction using the sin²ψ method. The relative permittivity of the PZT/Cu films was measured as a function of applied AC electric field. By performing a Rayleigh analysis on this data one can determine the relative contributions of the intrinsic, reversible, and irreversible components to the permittivity. The residual stress could be correlated to the reversible part of the permittivity. The first order reversal curves (FORCs), which characterize the ferroelectric switching, give indications of the defect state of the film. Cantilever energy harvesters were fabricated. Large electrodes were able to be evaporated onto the films after oxidizing pinholes and cracks on a hot plate. Devices were tested on a shaker table at < 100 Hz. A dynamic model based on Euler-Bernoulli beam equations was used to predict power output of the fabricated devices. The observed output was comparable to model predictions. Resonant frequency calculations were in line with observed first and second resonances at ~17 Hz and ~35 Hz which were also close to those predicted by the dynamic model. / Graduation date: 2013

With the digital systems moving towards higher frequencies, lower operating voltages and higher power, supplying the required current at the right voltage and at the right time to facilitate timely switching of the CMOS circuits becomes increasingly challenging. The board level power supply cannot meet these requirements directly due to the high inductance of the package interconnections. To overcome this problem, several thin film decoupling capacitors have to be placed on the IC or close to the IC in the package. Two approaches were pursued for high-k thin film decoupling capacitors. 1) Low cost sol-gel based thin film capacitors on organic board compatible Cu-foils 2) RF-sputtered thin film capacitors on silicon substrate for silicon compatible processes While sol-gel provides cost effective technology, sputtered ferroelectric devices are more compatible from manufacturing stand point with the existing technology. Nano-crystalline barium titanate and barium strontium titanate film capacitor devices were fabricated and characterized for organic and silicon substrates respectively. Sol-gel barium titanate films were fabricated first on a bare Cu-foil and then transferred to organic board through a standard lamination process. With process optimization and film doping, a capacitance density of 3 µF/cm2 was demonstrated with breakdown voltage greater than 12V. Leakage current characteristics, breakdown voltages, and electrical reliability of the devices were significantly improved through doping of the barium titanate films and modified film chemistry. Films and interfaces were characterized with high resolution electron microscopy, SEM, XRD, and DC leakage measurements. RF sputtering was selected for ferroelectric thin film integration on silicon substrate. Barium strontium titanate (BST) films were deposited on various electrodes sputtered on silicon substrates. The main focus was to improve interface stabilities for high-k thin films on Si to yield large-area defect-free devices. Effect of bottom electrode selection and barrier layers on device yield and performance were investigated carefully. High yield and high device performance was observed for certain electrode and barrier layer combination. A capacitance density up to 1 µF/cm2 was demonstrated with a breakdown voltage above 15 V on large area, 7 mm2, devices. These two techniques can potentially meet mid-high frequency future decoupling requirements.

This diploma thesis is mainly focused on the fabrication of graphene layers on the copper foil by the Chemical Vapor Deposition (CVD). For this purpose the high-temperature chamber for the production of the graphene was completed and fully automated. The production of the high area graphene on the copper foil was experimentally achieved. The Raman microscopy and X-ray photoelectron spectroscopy measurements proved that the produced graphene is mostly a monolayer. Graphene layer was transferred on non-conductive substrate.

Diplomová práce se zabývá teoretickými výpočty a návrhem struktury pro přenos tepla, která je součástí Miniaturizovaného tepelného spínače podle zadaných požadavků Evropské Kosmické Agentury. Základními parametry jsou nízká hmotnost a vysoká tepelná vodivost. Práce navazuje na spínač navržený firmou Arescosmo, který nesplňoval požadované limity zejména v oblasti hmotnosti a tepelné vodivosti. Pomocí teoretických výpočtů hmotnosti a tepelné vodivosti bylo ověřeno 49 variant ve třech základních konceptech – Mechanická struktura, flexibilní struktura složená z drátků a foliová struktura. Z hlediska tepelné vodivosti jako nejlepší struktury vycházejí ty, které jsou založené na použití ochranných kovových opletů. Z dostupných zdrojů byly rovněž navrženy technologie, které by bylo možné využít pro výrobu těchto struktur. Pro splnění požadavků, bude v další fázi projektu nutné vyrobit experimentální vzorky na kterých budou teoretické výpočty a vybrané technologie ověřeny.