• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2012.05a
• /
• pp.193-194
• /
• 2012

레이저클리닝이란 레이저빔을 표면에 조사하여 오염 물질을 제거하는 공정 기술로서 건식 세정방식이다. 본 연구에서는 레이저클리닝을 금속문화재에 코팅된 아크릴수지에 적용하여 제거 가능성 및 표면 특성을 조사하였다. 실험 결과 소지금속에 손상을 주지 않으면서 아크릴수지를 제거하는 레이저 조건을 확인하였으나 청동유물에 적용한 결과 아크릴수지와 파티나 층이 함께 제거되는 레이저클리닝의 문제점도 확인할 수 있었다. 앞으로 다양한 레이저 시스템 및 파장별 실험을 진행하여 청동 파티나층의 제거 가능성을 검토하면 레이저 클리닝을 청동 문화재에 적용하는데 도움이 될 것으로 본다.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.30 no.4
• /
• pp.307-314
• /
• 2014

Although a laser has been introduced to implant dentistry for decades, its efficacy is still open debate. The aim of this literature review is to analyze and evaluate the efficacy of laser therapy for the treatment of dentinal hypersensitivity and periodontal conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.223-224
• /
• 2013

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2007.11a
• /
• pp.16.2-16.2
• /
• 2007

• Laser Solutions
• /
• v.12 no.4
• /
• pp.17-25
• /
• 2009

The surface cleaning method based on the laser-induced breakdown (LIB) of gas and subsequent plasma and shock wave generation can remove small particles from solid surfaces. In the laser shock cleaning (LSC) process, a high-power laser pulse induces optical breakdown of the ambient gas above the solid surface covered with contaminant particles. The subsequently created shock wave followed by a high-speed flow stream detaches the particles. In this work, a novel surface cleaning process using laser-induced breakdown of liquid is introduced and demonstrated. LIB of a micro liquid jet increases the shock wave intensity and thus removes smaller particle than the conventional LSC method. Experiments demonstrate that the cleaning force and cleaning efficiency are also increased significantly by this method.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.8
• /
• pp.31-36
• /
• 2004

we developed a technique to manufacture more reliable polycrystalline silicon TFT-LCDs using UV cleaning and buffered oxide etch(BOE) cleaning which remove the native oxide of the silicon surface before laser annealing. To investigate the effects of pre-treatments on the surface roughness of polycrystalline silicon, we measured atomic force microscopy(AFM). Also the electrical characteristics of polysilicon TFTs, breakdown characteristic and switching Performance, were tested for various pre-treatment conditions and several locations in large glass substrate.

• Journal of the Korean Vacuum Society
• /
• v.6 no.1
• /
• pp.9-19
• /
• 1997

The reaction mechanisms of dry cleaning with UV-excited chlorine radical for Zn, Fe and Ti trace contaminants on the Si wafer have been studied by SEM, AFM and XPS analyses in this work. The patterned Zn, Fe and Ti films were deposited on the Si wafer surface by thermal evaporation and changes in the surface morphology after dry cleaning with $Cl_2$and UV/$Cl_2$at $200^{\circ}C$ were studied by optical microscopy and SEM. In addition, changes in the surface roughness of Si wafer with the cleaning was observed by AFM. The chemical bonding states of the Zn, Fe and Ti deposited silicon surface were observed with in-line XPS analysis. Zn and Fe were easily cleaned in the form of volatile zinc-chloride and iron-chloride as verified by the surface morphology changes. Ti which forms involatile oxides was not easily removed at room temperature but was slightly removed by UV/$Cl_2$at elevated temperature of $200^{\circ}C$. It was also found that the surface roughness of the Si wafer increased after $Cl_2$and UV/$Cl_2$cleaning. Therefore, the metallic contaminants on the Si wafer can be easily removed at lower temperature without surface damage by a continuous process using wet cleaning followed by UV/$Cl_2$dry cleaning.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2006.05a
• /
• pp.20.1-20.1
• /
• 2006

• Journal of Dental Rehabilitation and Applied Science
• /
• v.31 no.4
• /
• pp.340-348
• /
• 2015

Peri-implantitis is the most common reason for a late failure and can occur even after years of successful osseointegration. The role of microbial plaque accumulation in the development of peri-implantitis has been well documented. On the other hand, the ideal method of implant surface decontamination to re-establish the health of peri-implant tissue remains to be determined. Removal of bacterial deposits is essential in the treatment of peri-implant infections, and various therapeutic approaches have been described in the literature, including mechanical debridement, disinfection with chemotherapeutic agents, and laser therapy. Recently, there has been a plenitude of scientific data regarding the use of laser irradiation to achieve titanium surface decontamination. Thus, research is focusing on lasers' potential use in the treatment of peri-implantitis. The aim of this literature review is to analyze and evaluate the efficacy of laser therapy for the treatment of peri-implantitis.

• Journal of Conservation Science
• /
• v.34 no.6
• /
• pp.525-538
• /
• 2018

Myazedi Quadrilingual Stone Inscription of Myanmar, inscribed to the World Heritage List in 2015, is a rare historical artifact which has an exact date of inscription. It is a written record that displays the history, religion, and culture of Myanmar. Since the surface of the Stone Inscription has been rubbed with ink many times during the process of making printed copies for interpretation and academic research, it has developed a serious stain problem. Therefore, scientific analysis of the stain and research on the treatment for its removal have been conducted. In particular, an experiment was conducted on stain removal using laser cleaning and chemical treatment. The stains are mostly ink dirt, which accumulated from previous ink-rubbing processes. In order to conduct the experiment under similar conditions, a sample with similar stain has been reproduced, and a set of different conditions for treatment was applied to the sample to determine an effective solution. Laser cleaning was found to be effective in removing stains from most samples. However, chemical treatment showed different results. The physical friction method using ethanol provided the best result. In conclusion, laser cleaning is an effective universally-applicable technique but chemical treatment with laser cleaning can be considered an alternative method in certain situations.