The structural and electrical properties of amorphous BaSm2Ti4O12 (BSmT) films on a TiN/SiO2/Si substrate deposited using a RF magnetron sputtering method were investigated. The deposition of BSmT films was carried out at 300˚C in a mixed oxygen and argon (O2 : Ar = 1 : 4) atmosphere with a total pressure of 8.0 mTorr. In particular, a 45 nm-thick amorphous BSmT film exhibited a high capacitance density and low dissipation factor of 7.60 fF/μm2 and 1.3%, respectively, with a dielectric constant of 38 at 100 kHz. Its capacitance showed very little change, even in GHz ranges from 1.0 GHz to 6.0 GHz. The quality factor of the BSmT film was as high as 67 at 6 GHz. The leakage current density of the BSmT film was also very low, at approximately 5.11 nA/cm2 at 2 V; its conduction mechanism was explained by the the Poole-Frenkel emission. The quadratic voltage coefficient of capacitance of the BSmT film was approximately 698 ppm/V2, which is higher than the required value (<100 ppm/V2) for RF application. This could be reduced by improving the process condition. The temperature coefficient of capacitance of the film was low at nearly 296 ppm/˚C at 100 kHz. Therefore, amorphous BSmT grown on a TiN substrate is a viable candidate material for a metal-insulator-metal capacitor.

A new cost-effective atomic layer deposition (ALD) technique, known as Proximity-Scan ALD (PS-ALD) was developed and its benefits were demonstrated by depositing Al2O3 and HfO2 thin films using TMA and TEMAHf, respectively, as precursors. The system is consisted of two separate injectors for precursors and reactants that are placed near a heated substrate at a proximity of less than 1 cm. The bell-shaped injector chamber separated but close to the substrate forms a local chamber, maintaining higher pressure compared to the rest of chamber. Therefore, a system configuration with a rotating substrate gives the typical sequential deposition process of ALD under a continuous source flow without the need for gas switching. As the pressure required for the deposition is achieved in a small local volume, the need for an expensive metal organic (MO) source is reduced by a factor of approximately 100 concerning the volume ratio of local to total chambers. Under an optimized deposition condition, the deposition rates of Al2O3 and HfO2 were 1.3 Å/cycle and 0.75 Å/cycle, respectively, with dielectric constants of 9.4 and 23. A relatively short cycle time (5~10 sec) due to the lack of the time-consuming "purging and pumping" process and the capability of multi-wafer processing of the proposed technology offer a very high through-put in addition to a lower cost.

The effects of the deposition and annealing temperature on the structural, electrical and opticalproperties of Ag doped ZnO (ZnO:Ag) thin films were investigated. All of the films were deposited with a 2wt%Ag2O-doped ZnO target using an e-beam evaporator. The substrate temperature varied from room temperature(RT) to 250oC. An undoped ZnO thin film was also fabricated at 150oC as a reference. The as-grown films wereannealed in temperatures ranging from 350 to 650oC for 5h in air. The Ag content in the film decreased asthe deposition and the post-annealing temperature increased due to the evaporation of the Ag in the film.During the annealing process, grain growth occurred, as confirmed from XRD and SEM results. The as-grownfilm deposited at RT showed n-type conduction; however, the films deposited at higher temperatures showedp-type conduction. The films fabricated at 150oC revealed the highest hole concentration of 3.98×1019cm-3 anda resistivity of 0.347Ω·cm. The RT PL spectra of the as-grown ZnO:Ag films exhibited very weak emissionintensity compared to undoped ZnO; moreover, the emission intensities became stronger as the annealingtemperature increased with two main emission bands of near band-edge UV and defect-related greenluminescence exhibited. The film deposited at 150oC and annealed at 350oC exhibited the lowest value of Ivis/Iuv of 0.05.

Amorphous BaTi4O9 (BT4) film was deposited on Pt/Si substrate by RF magnetron sputter and their dielectric properties and electrical properties are investigated. A cross sectional SEM image and AFM image of the surface of the amorphous BT4 film deposited at room temperature showed the film was grown well on the substrate. The amorphous BT4 film had a large dielectric constant of 32, which is similar to that of the crystalline BT4 film. The leakage current density of the BT4 film was low and a Poole-Frenkel emission was suggested as the leakage current mechanism. A positive quadratic voltage coefficient of capacitance (VCC) was obtained for the BT4 film with a thickness of<70 nm and it could be due to the free carrier relaxation. However, a negative quadratic VCC was obtained for the films with a thickness ≥96nm, possibly due to the dipolar relaxation. The 55 nm-thick BT4 film had a high capacitance density of 5.1fF/μm2 with a low leakage current density of 11.6nA/cm2 at 2 V. Its quadratic and linear VCCs were 244ppm/V2 and -52 ppm/V, respectively, with a low temperature coefficient of capacitance of 961ppm/˚C at 100 kHz. These results confirmed the potential suitability of the amorphous BT4 film for use as a high performance metal-insulator-metal (MIM) capacitor.

The relationship between electrical properties of superconductor and externally applied magnetic field was studied to develop a magnetic field sensor. The electrical resistance of the superconductor was increased by applying external magnetic field and even after removal of the magnetic field. This behavior was related to the magnetic flux trapped in the superconductor, which penetrated through the material by the external magnetic field. Some portion of the superconductor was changed to a normal state by the trapped magnetic flux. The appearance of the normal state yielded to enhance the electrical resistance.

1mm-thick BLT ceramics were sintered in accordance with a bulk ceramic fabrication process. All XRD peaks detected in the sintered ceramics were indexed as the Bi-layered perovskite structure without secondary phases. Density was increased with increasing the sintering temperature up to and the maximum value was about 98% of the theoretical density. The remanent polarization (2Pr) value of BLT ceramic sintered at was approximately at the applied voltage of 4.5kV. From these results, a BLT ceramic target for plused laser deposition (PLD) system was successfully fabricated.