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Full-Text Articles in Physics
Plasma Characteristics And Ion Etching Performance In Hard Disk Drive Slider Fabrication Processes, Napakan Wongpanit
Plasma Characteristics And Ion Etching Performance In Hard Disk Drive Slider Fabrication Processes, Napakan Wongpanit
Chulalongkorn University Theses and Dissertations (Chula ETD)
A hard disk drive (HDD) is the permanent magnetic data storage and one of the most important components of computers, electronic devices and cloud data storage service facility. The data reading and writing are operated by the reader and writer parts of HDD head or slider. These reader and writer were made of multilayer thin ilms of different materials, forming a tunneling magnetoresistive (TMR) device. In HDD production, the ion beam etching (IBE) process was used in the preparation of surface patterns and cleaning in many fabrication steps. The Monte Carlo-based simulation package, SRIM was applied to calculate the etching …
Enhancing H2s Sensing Response Of Calcium Copper Titanate Thin Films By Adding Ag Compounds, Aukrit Natkaeo
Enhancing H2s Sensing Response Of Calcium Copper Titanate Thin Films By Adding Ag Compounds, Aukrit Natkaeo
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ag-doped CaCu3Ti4O12 (CCTO) thin films with different doping concentrations were prepared by a sol-gel technique. Films were grown by depositing four layers of CCTO on alumina substrates followed by sputtering Au/Cr interdigitated electrodes to fabricate gas sensors. The films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) Raman spectroscopy and X-ray photoemission spectroscopy (XPS). The films have predominantly the perovskite CCTO crystal phase with very small amount of TiO2 secondary phases. In this thesis, both undoped CCTO and Ag-doped CCTO thin films were tested for selective sensing to H2S gas relative …
Effects Of Gamma Ray Irradiation On Structural And Optical Properties Of Csi:Tl Crystals, Poramin Sintham
Effects Of Gamma Ray Irradiation On Structural And Optical Properties Of Csi:Tl Crystals, Poramin Sintham
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research work, effects of gamma ray irradiation on structural and optical properties of CsI doped with Tl (CsI:Tl), which is a scintillator material used for radiation detector applications, were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), UV-VIS spectroscopy and X-ray luminescence spectroscopy. The CsI:Tl crystals used in this study were grown by a modified homemade Bridgman-Stockbarger technique with CsI powder precursors purities of 99.999% and 99.9% and with the same amount of Tl in form powder of Tl. It is observed that CsI:Tl crystal grown with the 99.999% CsI powder precursor exhibited a colorless …
Tribological Characterization Of Lapping Lubricant In Hard Disk Drive Fabrication, Sawanee Jitphayomkun
Tribological Characterization Of Lapping Lubricant In Hard Disk Drive Fabrication, Sawanee Jitphayomkun
Chulalongkorn University Theses and Dissertations (Chula ETD)
One of the most important processes in hard disk drive fabrication is the lapping process. As two bodies are in contact, the friction occurs, and the softer material can be worn out by the harder. By using lubricant in the lapping process, it does not only reduce the friction, but it also transfers heat and captures debris away from the surface contacts. This thesis work focused on the effects of tribological parameters toward the characteristics of lubricants, using ball-on-disk tribometer. The tribological behaviors between using different base lubricants were investigated. At the same condition as final lapping process, EG-based and …
Gas Sensing Response Of Nickel Doped Calcium Copper Titanate Thin Films Synthesized By Sol-Gel Method, Arisara Boontum
Gas Sensing Response Of Nickel Doped Calcium Copper Titanate Thin Films Synthesized By Sol-Gel Method, Arisara Boontum
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nickel-doped calcium copper titanate (Ni-doped CCTO) thin films prepared by nickel oxide (NiO) and nickel (II) acetate (C4H6NiO4) have been synthesized using sol-gel method. Four layers of Ni-doped CCTO films with various nickel dopant concentrations including undoped film were deposited by a spin coating technique on silicon and alumina substrates. Each film layer was annealed at a fixed annealing temperature of 800 °C. All samples were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) field emission scanning electron microscope (FESEM). Only the doped films prepared by NiO were analyzed by Raman spectroscopy. Moreover, the …
Effect Of Tio2 Morphology On Efficiency Of Ch3nh3pbi3 Perovskite Solar Cells, Ramon Songtanasit
Effect Of Tio2 Morphology On Efficiency Of Ch3nh3pbi3 Perovskite Solar Cells, Ramon Songtanasit
Chulalongkorn University Theses and Dissertations (Chula ETD)
A TiO2 compact (cp) layer or blocking layer (bl) plays a crucial role in a hybrid organic-inorganic lead halide perovskite solar cell (PSC) because it prevents the carrier recombination at the interface of fluorine-doped tin oxide (FTO) and perovskite layers. In this work, fabrication, characterizations of cp-TiO2 and their effects on the PSC were studied. The cp-TiO2 layers in this work were fabricated by radio frequency (RF)-magnetron sputtering method and spin coating method with various conditions. The cp-TiO2 layer was incorporated into the PSC device structure consisting of Au/spiro-OMeTAD/MAPbI3/mp-TiO2/cp-TiO2/FTO. For the sputtering method, cp-TiO2 could selectively block the transport of …