Spatially resolvable optical emission spectrometer for analyzing density uniformity of semiconductor process plasma.

We proposed a spatially resolved optical emission spectrometer (SROES) for analyzing the uniformity of plasma density for semiconductor processes. To enhance the spatial resolution of the SROES, we constructed a SROES system using a series of lenses, apertures, and pinholes. We calculated the spatial resolution of the SROES for the variation of pinhole size, and our calculated results were in good agreement with the measured spatial variation of the constructed SROES.

Synthesis of titanate nanotube from different phases of TiO2 powders and its hydrogen absorption capacity.

Titanate nanotubes were synthesized by hydrothermal method with different NaOH concentration using various TiO2 powders (P-25, rutile, anatase, and Ni doped TiO2) at 120 degrees C for 24 hrs. At 10 M NaOH, Ni doped TiO2 powders formed the titanate nanotubes which consisted of layered structure such as A2Ti2O5.H2O, A2Ti3O7, H2TiO.

Synthesis and characterization of titanate nanotube for hydrogen storage using hydrothermal method with various alkaline treatment.

Titanate nanotubes and nanofibers were synthesized by hydrothermal method using various alkaline solutions (NaOH and KOH) in order to study the effect of synthesis condition for hydrogen storage. The microstructures of titanate nanotube and nanofibers were characterized by XRD, TEM, FE-SEM. It was found that interlayer spacing of titanate nanotubes and nanofibers depended on the alkaline solution, because some of the Ti-O-Ti bonds were broken and layered titanate nanosheet of Ti-O-A (Na+ and K+) bonds were formed.

Structural characterization of titanate nanotubes for lithium storage.

Titanate nanotubes were synthesized by hydrothermal method using various TiO2 precursors as starting materials. The electrochemical properties were investigated by cyclic voltammetric methods. The microstructure and morphology of the synthesized powders were characterized by XRD, TEM.