• Korean Journal of Materials Research
• /
• v.12 no.5
• /
• pp.327-333
• /
• 2002

In order to obtain the oxidation layer for SiC MOS, the oxide layers by thermal oxidation process with dry and wet method were deposited and characterized. Deposition temperature for oxidation layer was $1100^{\circ}C$~130$0^{\circ}C$ by $O_2$ and Ar atmosphere. The oxide thickness, surface morphology, and interface characteristic of deposited oxide layers were measurement by ellipsometer, SEM, TEM, AFM, and SIMS. Thickness of oxidation layer was confirmed 50nm and 90nm to with deposition temperature at $1150^{\circ}C$ and $1200{\circ}C$ for dry 4 hours and wet 1 hour, respectively. For the high purity oxidation layer, the necessity of sacrificial oxidation which is etched for the removal of the defeats on the wafer after quickly thermal oxidation was confirmed.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.2C no.6
• /
• pp.309-313
• /
• 2002

In this paper, we have studied minimization of the kerf-width and surface burning, which occurred after the conventional singulation process of the multi-layer BGA board with copper, polyethylene and epoxy glass fiber. The high thermal energy of a pulsed Nd:YAG laser is used to cut the multi-layer board. The most considerable matter in the laser cutting of the multi-layer BGA boards is their different absorption coefficient to the laser beam and their different heat conductivity. The cut mechanism of a multi-layer BGA board using a 2$^{nd}$ harmonic Nd:YAG laser is the thermal vaporization by high temperature rise based on the Gaussian profile and copper melting point. In this experiment, we found that the sacrifice layer and Na blowing are effective in minimizing the surface burning by the reaction between oxygen in the air and the laser beam. In addition, N2 blowing reduces laser energy loss by debris and suppresses surface oxidation. Also, the beam incidence on the epoxy layer compared to polyimide was much more suitable to reduce damage to polyimide with copper wire for the multi layer BGA singulation. When the polyester double-sided tape is used as a sacrifice layer, surface carbonization becomes less. The SEM, non-contact 3D inspector and high-resolution microscope are used to measure cut line-width and surface morphology.

• Nutrition Research and Practice
• /
• v.14 no.5
• /
• pp.425-437
• /
• 2020

BACKGROUND/OBJECTIVES: Different fatty acids exert different health benefits. This study investigated the potential protective effects of perilla, olive, and safflower oils on high-fat diet-induced obesity and colon inflammation. MATERIALS/METHODS: Five-week old, C57BL/6J mice were assigned to 5 groups: low-fat diet (LFD), high-fat diet (HFD) and high-fat diet supplemented with-perilla oil (HPO), olive oil (HOO), and safflower oil (HSO). After 16 weeks of the experimental period, the mice were sacrificed, and blood and tissues were collected. The serum was analyzed for obesity- and inflammation-related biomarkers. Gene expression of the biomarkers in the liver, adipose tissue, and colon tissue was analyzed. Micro-computed tomography (CT) analysis was performed one week before sacrifice. RESULTS: Treatment with all the three oils significantly improved obesity-induced increases in body weight, liver weight, and epididymal fat weight as well as serum triglyceride and leptin levels. Treatment with perilla oil (PO) and safflower oil (SO) increased adiponectin levels. The micro-CT analysis revealed that PO and SO reduced abdominal fat volume considerably. The mRNA expression of lipogenic genes was reduced in all the three oilsupplemented groups and PO upregulated lipid oxidation in the liver. Supplementation of oils improved macroscopic score, increased colon length, and decreased serum endotoxin and proinflammatory cytokine levels in the colon. The abundance of Bifidobacteria was increased and that of Enterobacteriaceae was reduced in the PO-supplemented group. All three oils reduced proinflammatory cytokine levels, as indicated by the mRNA expression. In addition, PO increased the expression of tight junction proteins. CONCLUSIONS: Taken together, our data indicate that the three oils exert similar anti-obesity effects. Interestingly, compared with olive oil and SO, PO provides better protection against high-fat diet-induced colon inflammation, suggesting that PO consumption helps manage inflammation-related diseases and provides omega-3 fatty acids needed by the body.