¡@¡@Because of the poly-si thin film transistor have the advantage of high mobility, it can improve the analysis for the flat plan display. Using the above advantage can combine the integrated circuit as control IC and memory on the small panel to reduce the number between the switch circuits and the outside contacts. These precise circuits must be considering the photo current¡Bthermal effects and the parasitical capacitance more due to the influence of these precise circuits is more serious than the switch circuits. In my thesis, the research of the electrical characteristics of the newest excimer laser crystallize coplane poly-si thin film transistors ,and using the device length with width is 128um/6um and 128um/16um can be extracted that the environment of the facing illumination have the photo-leakage current than none illumination about four orders, and the photo-leakage current is not consider with any gate voltage. ¡@¡@With the discussion of the capacitance, the main point of my researches is to change different conditions to extract the gate to source capacitance (Cgs). In addition, the slight carriers may effect the devices with the high mobility system on panel (SOP) technology error, the temperature must be considered. ¡@¡@We find the mobility is bigger at the environment of the temperature is 300K than the environment of the temperature is 100K when the device work in the linear region and the on current is lower at the environment of the temperature is 300K than the environment of the temperature is 100K when the device work in the saturation region. Using some references and some models as the concepts can analysis some phenomenons I refer to above.

Semi-insulating gallium arsenide (SI-GaAs) has gained great interest in recent years due to its wide application in optoelectronic devices and high-speed integrated circuits. An important feature of SI-GaAs is the high density of deep-level defect states, which control the electrical properties of the substrate by compensating the shallow defects. Over the years, deep-level transient spectroscopy (DLTS) and its variations have been the most effective tools employed for the characterization of deep-level defects. However, most of these techniques require a contact probe and tend to be quite restrictive in their applications’ scope. In this thesis deep-level photo-thermal spectroscopy (DLPTS), an all-optical rate-window-based technique, is presented as a novel noncontact technique for the characterization of deep-level defects in SI-GaAs. The signal-generation mechanism for DLPTS is the super-bandgap excitation of carriers, and the sub-bandgap detection of the defect’s thermal-emission process. Combined with the rate-window detection utilizing lock-in amplifiers, DLPTS measurements are performed in three different modalities: temperature-scan, pulse-rate scan, and time-scan. This work demonstrates that each mode provides unique information about the defect configuration, and, in combination, the modes offer a powerful tool for the study of defect properties and optoelectronic processes in SI-GaAs. A hierarchical carrier-emission theory is proposed to explain the thermal broadening (nonexponentiality) in photo-thermal spectra. The model is studied comparatively with the Gaussian distribution of activation energies, and their similarities demonstrate an ergodic equivalence of random energy distribution and the constrained hierarchical emission process. In addition, a rate-window gated photo-carrier radiometry (PCR) technique is developed. The original diffusion-based PCR theory is modified to reflect the signal domination by trap emission and capture rates in the absence of diffusion. Defect luminescence is collected and analyzed using photo-thermal temperature spectra and resonant detection combined with frequency scans. The study results in the identification of five radiative defect states and the defect-photoluminescence quantum efficiency.

Semi-insulating gallium arsenide (SI-GaAs) has gained great interest in recent years due to its wide application in optoelectronic devices and high-speed integrated circuits. An important feature of SI-GaAs is the high density of deep-level defect states, which control the electrical properties of the substrate by compensating the shallow defects. Over the years, deep-level transient spectroscopy (DLTS) and its variations have been the most effective tools employed for the characterization of deep-level defects. However, most of these techniques require a contact probe and tend to be quite restrictive in their applications’ scope. In this thesis deep-level photo-thermal spectroscopy (DLPTS), an all-optical rate-window-based technique, is presented as a novel noncontact technique for the characterization of deep-level defects in SI-GaAs. The signal-generation mechanism for DLPTS is the super-bandgap excitation of carriers, and the sub-bandgap detection of the defect’s thermal-emission process. Combined with the rate-window detection utilizing lock-in amplifiers, DLPTS measurements are performed in three different modalities: temperature-scan, pulse-rate scan, and time-scan. This work demonstrates that each mode provides unique information about the defect configuration, and, in combination, the modes offer a powerful tool for the study of defect properties and optoelectronic processes in SI-GaAs. A hierarchical carrier-emission theory is proposed to explain the thermal broadening (nonexponentiality) in photo-thermal spectra. The model is studied comparatively with the Gaussian distribution of activation energies, and their similarities demonstrate an ergodic equivalence of random energy distribution and the constrained hierarchical emission process. In addition, a rate-window gated photo-carrier radiometry (PCR) technique is developed. The original diffusion-based PCR theory is modified to reflect the signal domination by trap emission and capture rates in the absence of diffusion. Defect luminescence is collected and analyzed using photo-thermal temperature spectra and resonant detection combined with frequency scans. The study results in the identification of five radiative defect states and the defect-photoluminescence quantum efficiency.

For the application of 802.11a wireless communication system, this thesis aims to develop a novel suspending antenna with periodic structures to reduce electromagnetic wave from substrate using electrochemical deposition, surface micromachining and bulk micromachining technologies. This research presents two particular structures to increase the bandwidth and the radiation efficient and to reduce the return loss of the antenna, including: (i) the optimum design of periodic structures to restrain electromagnetic wave from substrate and to reduce the return loss of the antenna. To reduce the effective dielectric constant of the silicon substrate and to increase the bandwidth of the antenna, anisotropic etching the backside of the silicon substrate formed regular cavities using bulk-micromachining technology, (ii) to utilize a suspending structure to reduce the power loss through the substrate and to confirm the result using high frequency simulator. The implemented Si-based suspending antenna with periodic structures were characterized by a commercial network analyzer under 1~8 GHz testing frequency range. All the bandwidth and the return loss of the antenna proposed in this thesis are extracted by the commercial simulation software. Based on the measurement results, the center frequency is equal to 4.85 GHz, the return loss is around -35.5 dB and the bandwidth is equal to 42.9% (3.75~5.8 GHz). Eventually, this thesis successfully develops a low-loss and broadband antenna with novel structures using high frequency simulator and MEMS technologies for 802.11a wireless communication system.

ABSTRACT The aim of this dissertation is to fabricate an optical transceiver based on Si-bench technology for light peak application. The transceivers are composed of hybrid integration of the vertical cavity surface-emitting lasers (VCSEL), photo diodes and multi-mode fibers (MMF) on the Si optical bench using V-groove and U-groove structures. We are able to passively align VCSEL to MMF and photo diode to MMF because of the accurately-aligned characteristic of V-groove. The 45-degree-angled fibers with mirror coating are used to bend the directions of both the incoming and outgoing lights to the photodiode and the MMF. The simulations showed that the optical losses of the transceiver are less than 10 dB when the distance between VCSEL and MMF is 250£gm.The measured optical losses between transmitting module and receiving module are less than 12 dB. Key words: Light Peak¡Boptical transceiver¡BSi-bench¡Baccurately-aligned

The electro-optical properties of the ZnO thin film are affected by the deposition parameters. In this study, we find the optimum growth parameters to grow high quality ZnO film. We change the RF power to adjust the surface roughness. The higher RF power will result in a higher deposition rate and rough surface roughness. We obtained an optimum surface roughness of 1.811nm at 50W RF power. The ZnO films have more than 80% transmittance in visible range, and obvious absorption in UV range. A significant peak in the wavelength of 385nm is observed in PL measurement. For the electric characteristics, the resistivity of as-grown ZnO films is high and decreases with post annealing treatment. We have obtained a minimum resistivity of 2.764¡Ñ10-2(£[-cm) at 700oC annealing treatment. Under the fixed 50RF power and 5sccm Ar flux, the optical characteristics and the crystal qualities are worse in the lower pressure (below 5mTorr). The ZnO films have lowest resistivity of 1.826¡Ñ10-2(£[-cm) in the 15mTorr and, strongest PL intensities in 25mTorr after 700oC annealing treatment. After the optimum growth condition, we enhance the optical characteristics through the surface Plasmon effect of the metal nanoparticles. The nano gold particles in the diameter of 50nm and 200-250nm can be obtained under the 5nm and 10nm Au film deposition and annealing at 700oC, respectively. For the optical characteristics, the PL intensity and optical transmittance are enhanced dependent on the size and position of the gold nanoparticles. For the electric characteristics, the n-ZnO/p-Si shows a good rectification effect. The mechanisms of current conduction are space charge current limit, and tunnel current. Sample with 50nm diameter has a significant space charge current limit mechanism. In the C-V measurement, we observed the hysteresis curve in the sample with gold nanoparticles. The sample with larger gold particles have larger memory window of ¡µVFB=0.23.

The reasons to cause the variation of the Fu-Long resort area have been investigated in the study. The resort area is the spit extended from the northern coast of the Shung-si River located at the northeast part of Taiwan. Historical coastlines and the bathymetry surveyed in the last 15 years have been used to interpret the cause of the coastline variation. Numerical simulation of the wave and flow field is performed to assist the interpretation. It is found that the spit may be eroded during typhoon season by the flood from Shung-si River and recovered in the next year if the typhoon occurred in monsoon season in which the eroded sediment carried by northward monsoon waves will be merged to the coastline by the following southward northeast season waves. On the contrary, if the typhoon occurred during northeast wind season, the accompanying southward will carry the eroded sediment further south and the spit may not recover in the next year. It is further found that the source of the sediment from the river has been decreased in the last decade and the coastline retreated in responding the source decrease. Man-made fishery port close to the spit also deposited some sediment and may cause the variation of the coastline.

The operating characteristics of non-volatile memory for modern requirement are high-density , low power consumption, fast read and write speed, and good reliability. The floating gate memory generated leakage path in the tunnel oxide during the trend of scaling down, which will result in the loss of all stored charge to the silicon substrate. As the data retention time and endurance are taken into consideration, the thickness of tunnel oxide exist a physical limit, owing to the demand of high-density capacities. RRAM is offered as an option in the next generation non-volatile memories, due to the following advantages: (1) simple structure and easy to process, and low cost ; (2) less restrictive in the scaling-down process; (3) with the multi-bit data storage features; (4) high speed operation; (5) Repeat write and read is more than one million. In the thesis, we use a simple and low-temperature process to form the silicon germanium oxide (Si-Ge-O) RRAM and silicon germanium oxide RRAM with nitrogen doping between the electrode and silicon-germanium oxide interface. By sputtering at argon and oxygen (Ar/O2), and sputtering at argon and ammonia (Ar/NH3) with silicon-germanium target to form silicon germanium oxide RRAM and silicon germanium oxide (Si-Ge-O)/silicon germanium oxnitride (Si-Ge-O-N) RRAM. By informing a SiGeON layer between the interface of electrode and silicon-germanium oxide improve the stability of write voltage and endurance reliability. In addition, both silicon and germanium are useful as materials in the optoelectronics industry and extensively studied in material science. Based on the two materials, the smiting characterizations of RRAM will be improved in the read-write stability and operation reliability.

In this thesis, we study a series of Si-doped GaN thin films and nanodots. These samples are growth on c-face sapphire substrate by Molecular Beam Epitaxy. In Si-doped GaN thin film growth, different Si cell temperature are used to control the dopant concentration. Van der Pauw hall measurement is used to measure the carrier concentrations and the mobilities. As increase Si cell temperature, the carrier concentration and the mobility increase. The maximum carrier concentration is 8 ¡Ñ 1019 cm-3, and the maximum mobility is 194 cm2/V-s. As increasing the Si dopant concentration, the near band edge photoluminescence emission peak intensity increases, but the full width at half maximum broaden from 47 meV to 117 meV. In Raman measurement result, with the increasing of Si dopant concentration, the E2(high) mode shifts from 569.4 cm-1 to 567.9 cm-1. The A1(LO) mode disappears gradually. In the nanodot growth, the AFM images show that the nanodots size become large as increasing the growth time. The nanodots size is change from 1.2 nm to 5.6 nm high and 40 nm to 110 nm wide, but the density of the nanodots decreases from 1.9 ¡Ñ 1010 cm-2 to 6 ¡Ñ 109 cm-2 at 15 sec and 90 sec growth, respectively. According to the AFM image of the nanodots surface morphology, the nanodots growth mode should be the Stranski-Krastanow mode.

Closed-vessel microwave assisted volatilization of Ge, Se, Si and quartz as their volatile compounds , for the determination of trace impurities in high purity Ge, Se, Si and quartz is reported. The volatilization of Ge is 98.7% using vapors of aqua regia whereas vapors generated from 72:1 ratio of HCl:HNO3 is required to volatilize 99.2% of Se. Using vapor of 10:5 ratio of HF:HNO3 , the volatilization of Si is 98.6%, and the volatilization of quartz is 99.0% with 15:3 ratio of the mixed acids. The recoveries of Mg, Cr, Mn,, Ni, Co, Cu, Zn, Cd, Ba and Pb are in the range 83-116%. Determinations are carried out using inductively coupled plasma mass spectrometer with Dynamic Reaction CellTM (DRC ICP-MS). Isobaric interferences, due to the formation of 40Ar12C+, 35Cl16OH+, 40Ar16O+ and 40Ar74Ge+ on the determination of 52Cr+, 56Fe+ and 114Cd+, have been alleviated using ammonia cell gas in DRC. Matrix volatilization using in situ generated acid vapors in closed containers resulted in sub ng mL-1 experimental blanks. Method detection limits are in the low ng g-1 level. The methods developed have been applied to determine trace impurities in high purity Ge, Se, Si and quartz samples.