• 대한치주과학회:학술대회논문집
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• 2005.11a
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• pp.65-65
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• 2005

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1055-1056
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• 2013

• Restorative Dentistry and Endodontics
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• v.13 no.2
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• pp.323-334
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• 1988

The purpose of this study was to observe the effect of dentin surface conditioners on the dentin surfaces. Freshly extracted human molars were used in this study. They were stored at $4^{\circ}C$ saline solution before experiment. The crown portions of the teeth were cut in various directions by means of wet diamond point to expose dentin which include transverse, vertical oblique, horizontal and oblique cut to the long axis (Fig. 1). Each tooth was then mounted with self curing acrylic resin in brass ring to expose the flattened dentin surfaces. Final finish was accomplished by grinding the dentin specimens with wet No. 180 and No. 600 grit silicon carbide abrasive paper until a 6.0mm in diameter on a dentin surface was exposed without pulp exposure. The specimens were divided into 9 groups according to the modes of dentin treatment procedure. The following surface treatments were applied on these preparation surfaces; Group 1: unetched (control group) after finish with No. 600 silicon carbide abrasive paper. Group 2: etched with 30% phosphoric acid for 60s Group 3: etched with 10-3 solution for 60s Group 4: Cleaned with 5% NaOCl for 30s Group 5: applied Dentin Adhesit Group 6: cleaned with 5% NaOCl followed by applying the Dentin Adhesit$^{(R)}$ Group 7: applied Photo Bond on the unetched dentin followed by applying the Photo Clearfil Bright Group 8: Etched with 30% phosphoric acid followed by applying Photo Bond and Photo Clearfil Bright Group 9: etched with 10-3 solution followed by applying Photo Bond and Photo Clearfil Bright All the specimens were stored in $37^{\circ}C$ under 50% relative humidity for 24 hours before observations. The specimens in 7, 8, and 9 group, omitting the group 1 to 6, were demineralized in 10% HCl for 10s in order to observe the resin tags. All the specimens in each group were then dried at room temperature. The dried specimens were ion coated with Eiko ion coater (Eiko-engineering Co.), and observed in Hitachi S-430 Scanning electron microscope (Hitachi, Co. Tokyo) at 15KV. The following results were obtained as follows; 1. The smear layers were still remained in group 1,2,4,5, and 6. 2. There is no effect of 5% NaOCl and 30% phosphoric acid on the changes of dentin morphology 3. The dentin treated with 10-3 solution, indicating the tubules opened when the smear layer and the dental plug dissolved. 4. In case of applying the bonding agents the resin tag was not formed at the deep area of dentinal tubules, but in case of applying the Dentin Adhesit$^{(R)}$ that was not.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.5
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• pp.265-269
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• 2000

$(Ba, Sr)TiO_3$thin films were etched with a magnetically enhanced inductively coupled plasma (MEICP) at different CF4/Ar gas mixing ratios. Experimental was done by varying the etching parameters such as rf power, dc bias and chamber pressure. The maximum etch rate of the BST films was $1800{AA}/min$ under $CF_4/(CF_4+Ar)$ of 0.1, 600 W/350 V and 5 mTorr. The selectivity of BST to Pt and PR was 0.6, 0.7, respectively. X-ray photoelectron spectroscopy (XPS) results show that surface reaction between Ba, Sr, Ti and C, F radicals occurs during the (Ba, Sr)TiO3 etching. To analyze the composition of surface residue after the etching, films etched with different CF_4/Ar$ gas mixing ratio were investigated using XPS and secondary ion mass spectroscopy (SIMS).

• Journal of the Korean institute of surface engineering
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• v.28 no.2
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• pp.101-109
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• 1995

Electroetching rates of $FeCl_3$ solution were increased according to increasing solution temperature. Activation energy of electroetching at Be'36 and 5A/$dm^2$ condition was 28.3Kcal and also, at Be'46 and 5A/dm$^2$ condition was 33.2Kcal. At Be'36 concentration of $FeCl_3$ solution, electroetching rate were more higher than at Be'46 concentration. Surfaces of etched grooves obtained at 8A/$dm^2$ or higher current density in 46 Be' concentration of $FeCl_3$ solution were observed to be flat and smooth owing to suppressing chemical etching reaction. Distinctly etched boundaries became to be appeared at 2A/$dm^2$ in Be'41 electroetching condition by differential effects. In case of applying 8A/$dm^2$ current density to Be'46 of $FeCl_3$ solution, etching depth were 4 times and side etching were 6 times more than chemical etching case respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04b
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• pp.52-55
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• 2000

In this study, (Ba,Sr)$TiO_3$(BST) thin films were etched with a magnetically enhanced inductively coupled plasma(MEICP) as a function Ar/$CF_4$ gas mixing ratio. Experiment was done by varying the etching parameters such as rf power, dc bias voltage and chamber pressure. The maximum etch rate of the BST films was 1700 ${\AA}/min$ under $CF_4/(CF_4+Ar)$ of 0.1, 600 W/350 V and 5 mTorr. The selectivity of BST to Pt and PR was 0.6, 0.7, respectively. X -ray photoelectron spectroscopy(XPS) studies shows that there are surface reaction between Ba, Sr, Ti and C, F radicals during the etching. To analyze the composition of surface residue remaining after the etching, films etched with different $CF_4$/Ar gas mixing ratio were investigated using XPS.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.3
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• pp.231-236
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• 2005

To investigate the electrical properties at the single grainboundary of ZnO varistors, micro-electrodes were fabricated on the surface which was polished and thermally etched. Our micro-electrode had 2000 $\AA$ silicon nitride layer between micro-electrode and ZnO surface. This layer was deposited by PECVD and etched by RIE after photoresistor pattering process using by mask 1. The metal patterning of micro-electrodes used lift-off method. We found that the breakdown voltage of single grainboundary is about 3.5∼4.2 V at 0.1 mA on I-V curves. Also, capacitance-voltage measurement at single grainboundary gave several parameters( $N_{d}$, $N_{t}$, $\Phi$$_{b}$, t) which were related with grainboundary.ary.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.866-869
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• 2001

In this study, (Ba,Sr)TiO$_3$(BST) thin films were etched with a magnetically enhanced inductively coupled plasma(MEICP). Etching characteristics of BST thin films including etch rate and selectivity were evaluated as a function of the etching parameters such as gas mixing ratio, rf power, dc bias voltage and chamber pressure. The maximum etch rate of the BST films was 1700 $\AA$/min at Ar(90)/CF$_4$(10), 600 W/350 V and 5 mTorr. The selectivity of BST to PR was 0.6, 0.7, respectively. To analyze the composition of surface residue remaining after the etching, samples etched with different CF$_4$/Ar gas mixing ratio were investigated with X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). From the results of XPS and SIMS, there are chemical reaction between Ba, Sr, Ti and C, F radicals during the etching and remained on the surface.

• Corrosion Science and Technology
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• v.10 no.1
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• pp.37-42
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• 2011

Aluminum was electrochemically etched in acid solution and the surface area was magnified by the formation of etch pits. Etched aluminum was covered with a compact and dense dielectric oxide film by anodization and applied to the aluminum electrolytic capacitor electrode. Capacitance of aluminum electrolytic capacitor is closely related with surface area, which depends on size and number of etch pits. Size of etch pits need to be controlled because inside of the pits can be buried by the formation of dielectric oxide film. In this work, the effect of ultrasound pretreatment on the aluminum etch pit formation and capacitance were investigated. Additionally, the relationship between the second etching effect on pit size and capacitance was studied.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.600-602
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• 1995

Using the $O_2$ RIE process, 20{\mu}m$-height polyimide microstructures are fabricated. In LIGA-like process, metal microstructure can be formed by the electroplating using these polyimide microstructures as a plating mould. Reactive ion Etching technique using oxygen gas is used for the patterning of polyimide. The etching rate of the polyimide is increased with increased pressure and RF power. The anisotropic vertical sidewall can be obtained at low pressure, but the etched surface state is not so good yet. "Micrograss", which is formed during the RIE and disturbs uniform electroplating, can be removed effectively by the wet itching of the chromium sacrificial layer. More studies about the improvement of an etched surface state and the removal of microsgrass are needed.