Abstract In this thesis, we have fabricated a novel poly-Si thin film transistor with self-aligned SiGe raised source/drain (SiGe-RSD TFT). The SiGe-RSD regions were grown selectively by ultra-high vacuum chemical vapor deposition (UHVCVD) at 550¢J. The resultant transistor structure features a thin active channel region and a self-aligned thick source/drain region, which is ideally suited for optimum performance. A significant improvement on the turn-on current in the transfer characteristics is observed, compared to the conventional TFT counterpart. While the conventional TFT depicts severe resistance-limited output characteristics, especially at high gate bias, due to large source and drain series resistance. The new device, in contrast, exhibits excellent output characteristics. Finally, with comparable leakage current in both structures, the on/off current ratio is approximately 2 order of magnitudes higher in the proposed SiGe-RSD TFTS

In this thesis, the poly-Si TFTs with different channel width and channel length are successfully fabricated and characterized. In particular, by using the T-gate structure and body contact, we can measure the substrate current and body voltage. Therefore, short channel effects in polycrystalline silicon thin-film transistors are investigated clearly. In order to study impact ionization effect and floating body effect more carefully, we measure and compare the electrical behaviors of device with different grain boundary trap density, grain size, and channel dimension. The influences of these factors on the short channel effects are also discussed and explained. In this experiment, it is found that the devices with short channel length, exhibit improved normalized turn on current and smaller threshold voltage. But on the other hand the sever kink effect which generated by the impact ionization also observed. Moreover, the floating body under the channel region serve as a parasitic BJT as in silicon-on-insulator devices. The related single transistor latch-up is observed and discussed for short-channel devices with various channel width. The severe impact ionization effects in polycrystalline silicon thin-film transistors are investigated and characterized. By directly measuring the substrate current from conventional TFTs with body contact, the impact-ionization effects can be characterized and analyzed very clearly. An anomalous substrate current under high gate voltage is observed. The parasitic tunneling effect between inversion region and body region is proposed to explain this phenomenon. Finally, a physically-based model is established and compared with the measured substrate current. Good agreements are found when the vertical field scattering effect is included into the maximum electric field impact ionization model.

The purpose of this study is using titanium dioxide (TiO2) as gate oxide on thin film transistor (TFT) and discussed with their physical, chemical and electrical properties. Amorphous silicon (a-Si) and polycrystalline silicon (poly-Si) are used as substrates. The metal-organic chemical vapor deposition (MOCVD) and the liquid phase deposition (LPD) are used as the TiO2 growth methods. About the LPD growth method, ammonium hexafluoro-titanate ((NH4)2TiF6) and hexafluorotitanic acid (H2TiF6) are used as Ti sources. We are interested in two parts: (1) the growth mechanisms, physics properties, chemical properties and electrical properties of MOS structure; (2) the fabrication processes and electrical properties of devices. In the first part, we discuss the thin films characteristics on a-Si and poly-Si substrates. For the MOCVD growth method, the MOCVD-TiO2 film tends to form the poly structure. Poly structure has a higher dielectric constant, however, higher traps and dangling bonds also exist at the grain boundaries. Thus, poly structure of TiO2 film has a higher leakage current. For the LPD growth method, the film tends to form the amorphous structure. Amorphous structure has lower leakage current but also has lower dielectric constant. The film that grown from the (NH)2TiF6 source is called LPD-TiO2 film. The film that grown from the (NH)2TiF6 source is called LPD-TixSi(1-x)Oy film. Both films are incorporated with OH and F ions during the growth, the OH and F ions can be outgassed during the low temperature annealing process. In addition, appropriate F ions in the film can passivate the traps and dangling bonds. The low temperature treatments in N2 or O2 ambient and post-metallization annealing (PMA) are adopted to improve the film characteristics. On the other hand, the substrate is not a prefect structure (not a single structure). Thus the film may be influenced by substrate during the annealing treatment. In the second part, the electrical properties of TFT devices were discussed under the coplanar structure. There are several differences of the operation principle in TFT and MOSFET. A-Si and poly-Si are the un-doped substrates with many traps in the bulk. The channel should be occurred through the full depletion mode. The full depletion region is the substrate that under the gate electrode. Thus, the key point is kept the suitable thickness. Too thick, the channel can not appear. Too thin, the substrate may be over-etched. For ion implantation, due to the thinner active layer, the ion implantation energy should be lowed. In addition, the activation temperature and activation time should be adjusted suitable. We have fabricated the TFT devices with the MOCVD-TiO2 as gate oxide on poly-Si substrate. From the I-V characteristics, the Kink effect can be observed. However, the Ion/Ioff ratio is still low. We must further study how to increase the Ion/Ioff ratio.

Transparent InO (Indium oxide) thin-film transistors fabricated by reactive ratio frequency (rf) magnetron sputtering at room temperature were demonstrated on glass and plastic substrates. The resistivity, transmittance, X-ray diffraction pattern, and surface morphology of the films prepared at a 50% oxygen partial pressure were investigated, the resistivity and the average transmittance of the films were 4.2¡Ñ104 £[-cm and 87 %, respectively. In addition, Indium tin oxide (ITO) and silicon nitride (SiNX) thin films were used as the electrode and gate insulator. The resistivity and the average transmittance of ITO electrodes were 7¡Ñ10-4 £[-cm and 85%. On the other hand, the maximum leakage current of less than 10-9A/cm2 was obtained for the SiNX layer at an electric field of 1 MV/cm. For the InO TFT on glass substrate with 6 £gm channel length and 20 £gm channel width, the measured saturation mobility, threshold voltage, on/off ratio and subthreshold swing are 9.39V-1s-1, 1.5V, 2.2¡Ñ107and 0.5 V/decade. For the TFTs prepared on plastic substrate, the measured saturation mobility, threshold voltage, on/off ratio and subthreshold swing are 8.19V-1s-1, 1.83V, 1.43.¡Ñ106and 0.8 V/decade, respectively.

Oxide semiconductors have been envisaged to find applications in ubiquitous flexible electronics in daily life such as wearable electronic gadgets to offer novel user experiences. However, one of the bottlenecks to realise these applications is a lack of oxide-semiconductor components capable of wireless communications. As Bluetooth and Wi-Fi are the two dominant communication interfaces, fast enough front-end rectifiers must be developed to operate at their gigahertz (GHz) transmission frequencies. Furthermore, despite of significant developments of n-type oxide semiconductors in the last decade, widespread flexible electronics also requires high-performance p-type oxide semiconductors for use in complementary logic circuits. The objectives of this dissertation are to develop high quality Schottky barriers, achieve GHz speed Schottky diodes on rigid and flexible substrates, evaluate the noise properties of the Schottky diodes, develop p-type oxide semiconductor using sputtering technology, elucidate the hole transport mechanism in p type transistors, and demonstrate their potential applications such as radio receivers, complementary inverters and ring oscillators. First, indium gallium zinc oxide (IGZO) Schottky diodes were fabricated by using radio frequency magnetron sputtering. The oxygen content at the metal-IGZO interface was found to have a profound effect on the electrical performance. By introducing 3% O2 during the deposition of Pt or IGZO, the diodes exhibited excellent electrical properties without requiring any annealing treatment, thus allowing for the realisation of flexible IGZO Schottky diodes. The high-frequency properties of Pt-IGZO Schottky diodes on glass substrates were optimised by testing a range of IGZO thicknesses and diode active areas. The achieved highest cut-off frequency was beyond 20 GHz, which is to the best of our knowledge the fastest oxide-semiconductor device to date. On flexible substrates, the diodes also showed cut-off frequencies up to 6.3 GHz, well beyond the critical benchmark speed of 2.45 GHz for typical wireless communications. In order to assess the feasibility of using IGZO Schottky diodes in practical applications, measurements were taken to discern their low-frequency noise properties. In the as-deposited diodes, logarithmic dependence of the noise spectral density on the applied bias was observed, revealing that the dominant noise was generated in the space-charge region at low biases and in the series-resistance region at high biases, respectively. After annealing the diodes, very different noise mechanism was observed and the interface-trap-induced noise dominated the noise spectra. As one of the most promising p-type oxide semiconductors, SnO was also studied at low temperatures in this thesis. The experiment revealed that hole-transport mechanism was governed by either band conduction or variable range hopping in different temperature ranges. Finally, the potential for fully oxide-based electronics was demonstrated by an amplitude-modulation radio receiver comprising of an IGZO Schottky diode as the demodulator and a complementary ring oscillator based on IGZO and SnO transistors. In reference to IEEE copyrighted material which is used with permission in this thesis, the IEEE does not endorse any of the University of Manchester's products or services. Internal or personal use of this material is permitted. If interested in reprinting/republishing IEEE copyrighted material for advertising or promotional purposes or for creating new collective works for resale or redistribution, please go to http://www.ieee.org/publications_standards/publications/rights/rights_link.html to learn how to obtain a License from RightsLink.

<p>The purpose of this Master Thesis is to analyze what suitable hardware platforms there are on the market in order to build a low price control and information system for mobile applications, called small display module. The thesis will be underlying material for making a decision for further development. The result of the thesis consists mainly of a Windows CE kernel and a schematic for a CPU card, on which it would be suitable to build the display module. Another major part of the report is the introduction of different techniques that could be of interest when designing a processor based system. The processor architecture that was chosen is the x86. This is mainly due to CPU availability, but as well as the fact that existing software can be used on the display module without any significant modifications. Many interesting processors were sorted out because they hade a very high price on the development kits from the manufacturer and because the possible production volume can not manage this cost. The development kit makes the development easier and can be used for performance tests before prototypes are built.</p>

In this thesis, we propose a new thin-film transistor with trenched body and airgap-insulated structure (AITFT) for one-transistor dynamic random access memory (1T-DRAM) applications and investigate the influence of different materials on the sensing current window and retention time. Its basic operation mechanisms are based on the impact ionization and floating body effects. Due to the generated holes storing in the pseudo neutral region, the threshold voltage (Vth) is lower, resulting in a high drain current for state ¡§1¡¨. So we can recognize the data by sensing the difference of the drain current. According to the ISE TCAD 10.0 simulations, owing to the design of trench and airgap-isolation structure, the AITFT can enhance about 212% sensing current window and 42% retention time compared with the conventional TFT at the channel length of 150 nm and temperature of 300K conditions. Also, owing to the source/drain-tie, the generated heat can be dissipated quickly from the source/drain to the substrate thus the thermal instability is improved. In other words, the AITFT can improve the thermal reliability but without losing control of the short-channel effects.

In this thesis, we propose a simple trench oxide layer polysilicon thin-film Transistor (TO TFT) process and the self-heating effects can be significantly reduced because of its structural advantages. According to the ISE-TCAD simulation results, our proposed TO TFT structure has novel features as follows: 1. The buried oxide and the isolation oxide are carried out simultaneously in order to achieve a goal of simple process. 2. The trench design is used to improve both the sensing current windows (~ 84%) and the retention time (~ 57%). 3. The thermal stability is drastically improved by its naturally formed source/drain tie. The above mentioned features help our proposed device structure to demonstrate the desired characteristics that are better than that of a conventional TFT. Additionally, the thermal instability is drastically improved which is good for long-term device operation.

First of all, we put an emphasis on the global market status of TFT-LCD, which is also our government¡¦s most important economic investment in the near future. We think it is necessary for Taiwan cooperating with Japan to reach the global No.1 place in TFT-LCD industry since Japan initiates and masters many related technologies. A-Company; however, gets such right chance for multinational combination by taking good use of some key factors¡Xorganization integration, communication and human resources management. Because TFT-LCD products get short-lasting life and fast-advancing technology, A-Company must be greatly expanding its investment annually. Although the company has independent technologies, it still has to rapidly enhance its competitiveness on global purchase, global distribution and global service through making cooperation with other technical corporations. Thus, how to take advantage of both companies¡¦ interior resources to create even more high values is meaningful to A-Company. This research shows that organization integration, personal factors, organization promises and individual defense will affect merger achievements. We design a questionnaire and use SPSS for quantification analysis to strengthen the reliability and validity of our research. Lastly, we bring out the final results and conclusions for A-Company reference. According to the questionnaire we find out that, A-Company employees think the high-level managers play quite an important role in the organization integration; their communication and expression on human resource management will directly affect merger achievements. Nevertheless, the company seems not participate in the consolidating planning before combination and not elaborate on the communication after that which leads it into negative effects after combination. From this, we deeply realize that ¡§Manpower¡¨ is the most emphasized resource for consolidating business. Our conclusion is that many failure factors of overseas or domestic combination business are also applied to TFT-LCD Company, and therefore, we think that the success factors during its merger can be imitated by other industries as well. Anyhow, it¡¦s a real pity for A-Company¡¦s not taking good application to academic researches and some successful measures from other business. In sum, there are not only multinational cooperation but also multicultural races merging in the special TFT-LCD industry which reveals a fact that the affiliation of academia will speed up this industry¡¦s growth.

The original of industrial cluster analysis is to distinguish what is cluster. It is developing to overview industrial district and to conclude the potential industry. In the light of these defects, we cloud improve them for industrial development. This industrial cluster analysis of variables by literatures, including of Industrial Concentration Factor, Cluster Dependency Factor, Economic Prosperity Factor, and four strategic resources that influence development of cluster, including of High Quality Human Resource, Technology and Knowledge Resource, Infrastructure, Capital. Using the questionnaire and interview with members in the cluster. The results of research: (1)There is a orientation of TFT-LCD industrial cluster in the Southern Science Park and show a vertical industrial cluster than horizontal cluster. (2)Material and Key part of equipment is complete and available, but there is only one application firm that produces large TFT-LCD. (3) TFT-LCD industry is important in the district and creating economic development. (4)It is difficult to find many talents about TFT-LCD industry and High Quality Human Resource is positive effect to this cluster.(5)As a result of TFT-LCD industry is at initial stage, they have less demand of Technology and Knowledge Resource, but it is increasing in the future.(6)The films are satisfied of water and electricity system, but they think that the staff cloud not get better quality of life in the district.(7) As a result of using capital without borders and Taiwan¡¦s government take TFT-LCD industry seriously, the films get capital smoothly. Key words¡GSouthern Science Park ¡BThin-Film Transistor Liquid-Crystal Display ,TFT-LCD¡BIndustrial Cluster¡BLocation Quotient.