• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.62-62
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• 2003

Charged particles can be accelerated to relativistic high energies by high power (＞ terawatt) laser beams. We have a research project on laser and plasma-based advanced accelerators in Center for Advanced Accelerators at Korea Electrotechnology Research Institute (KERI), in which the 2 TW (1.4 J／700 fs) Ti：sapphire／Nd：glass hybrid laser system and a He plasma will be used for particle acceleration experiments. In this presentation, we introduce the ongoing research activities and the planned experiments at KERI.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.50-50
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• 2009

In this paper, the plasma doping is performed on p-type wafers using $PH_3$ gas(10 %) diluted with He gas(90 %). The wafer is placed in the plasma generated with 200 W and a negative DC bias (1 kV) is applied to the substrate for 60 sec under no substrate heating. the flow rate of the diluted $PH_3$ gas and the process pressure are 100 sccm and 10 mTorr, respectively. In order to diffuse and activate the dopant, annealing process such as rapid thermal annealing (RTA) is performed. RTA process is performed either in $N_2$, $O_2$ or $O_2+N_2$ ambient at $900{\sim}950^{\circ}C$ for 10 sec. The sheet resistance is measured using four point probe. The shallow n+/p doping profiles are investigated using secondary ion mass spectromtry (SIMS). The analysis of crystalline defect is also done using transmission electron microscopy (TEM) and double crystal X-ray diffraction (DXRD).

• Journal of the Korean Vacuum Society
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• v.8 no.4A
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• pp.490-495
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• 1999

In 0.18 $\mu \textrm m$ LOGIC device, the etch rate of NMOS polysilicons is different from that of PMOS polysilicons due to the state of polysilicon to manufacture gate line. To control the etch profile, we tested the ratio of $Cl_2$/HBr gas and the total chamber pressure, and also we reduced Back He pressure to get the vertical profile. In the case of manufacturing the gate photoresist line, we used Bottom Anti-Reflective Coating (BARC) to protect refrection of light. As a result we found that $CF_4O_2$ gas is good to etch BARC, because of high selectivity and good photoresist line profile after etching BARC. in the results of the characterization of plasma damage to the antenna effect of gate oxide, NO type thin film(growing gate oxide in 0, ambient followed by an NO anneal) is better than wet type thin film(growing gate oxide in $0_2+H_2$ ambient).

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.4
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• pp.47-50
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• 2006

SCM415 alloy was implanted with nitrogen ions using plasma source ion implantation (PSII), at a dose range of $1{\times}10^{17}\;to\;6{\times}10^{17}\;N^+cm^{-2}$ Auger electron spectrometry (AES) was used to investigate the depth profile of the implanted layer. Friction and wear tests were carried out on a block-on-ring wear tester. Scanning electron microscopy (SEM) was used to observe the micro-morphology of the worn surface. The results revealed that after being implanted with nitrogen ions, the frictional coefficient of the surface layer decreased, and the wear resistance increased with the nitrogen dose. The tribological mechanism was mainly adhesive, and the adhesive wear tended to become weaker oxidative wear with the increase in the nitrogen dose. The effects were mainly attributed to the formation of a hard nitride precipitate and a supersaturated solid solution of nitrogen in the surface layer.

• Archives of Plastic Surgery
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• v.44 no.6
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• pp.554-558
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• 2017

In many cases of complete ear amputation, microvascular surgery is required for tissue perfusion and organ survival. However, microvascular reconstruction is not always feasible in the absence of suitable vessels. Here, we present the case of a 76-year-old man who underwent complete amputation of the left ear after a collapse at home because of cardiogenic syncope. He was treated with primary replantation and underwent a postoperative salvage course including continuous local hyperbaric oxygen therapy (HBOT), platelet-rich plasma (PRP) injections, and polydeoxyribonucleotide (PDRN) injections. The ear was almost completely salvaged, with a tiny eschar at the mid-scapha on both the anterior and posterior aspects. This case demonstrates the efficacy of local HBOT with PRP and PDRN injections.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.175-176
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• 2000

Electric fields and the wall voltages in a surface-type AC PDP cell were measured using a Laser Induced Fluorescence Spectroscopy. For the condition of He 100Torr, 200V sustain voltage and 50kHz sustain frequency, the wall voltage dropped from about 50V to about -75V within $1{\mu}sec$ after the main discharge. And the wall voltage decreased with the rate of $10.8V/{\mu}sec$ due to the accumulation of the space charges after $1{\mu}sec$. But when the operating pressure was 40Torr, it increased with the rate of $4.5V/{\mu}sec$ because the diffusion effect of the wall charge on MgO surface was more dominant than the accumulation effect of the space charges. During the pulse-off period, the wall voltage decreased slightly due to the diffusion of the wall charge. When the sustain voltage was 250V, the self-erasing discharge occurred, and the absolute value of the wall voltage decreased rapidly just after the pulses were off, which was caused by the accumulation of the charges generated by the self-erasing discharge.

• The Korean Journal of Ceramics
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• v.3 no.3
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• pp.159-162
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• 1997

Diamond was uniformly nucleated on large area Si(001) substrate (3cm$\times$4cm) using the low pressure magnetoactive microwave plasma chemical vapor deposition. $CH_4/He$ gas mixture was used as source gas in order to obtain high radical density in the nucleation enhancement step. $CH_3$radical density was measured by means of infrared laser absorption spectroscopy. The effect of substrate bias voltage on diamond nucleation was examined. The results showed that a suitable positive bias voltage appled to the substrate with respect to the chamber could enhance diamond nucleation while a negative bias voltages leaded to deposition of only non-diamond phase carbon.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.1
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• pp.99-102
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• 2002

Pinholes on the thermally grown oxide, which is called gate oxide, on silicon substrate under polysilicon layer are found and its mechanism is analyzed in this paper. The oxide under a polysilicon layer is broken during the plasma etching process of other polysilicon layer. Both polysilicon layers are separated with 0.8${\mu}{\textrm}{m}$ thick oxide deposited by CVD (Chemical Vapor Deposition). Since broken oxide points are found scattered around an arc occurrence point, it is assumed that an extremely high electric field generated near the arc occurrence point makes the gate oxide broken. 1'he arc occurrence point has been observed on the alignment key and is the mark of low yield. It is found that any arc occurrence can cause chips to fail by breaking the gate oxide, even if are occurrence points are found on scribeline.

• Journal of The Korean Society of Clinical Toxicology
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• v.16 no.2
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• pp.172-175
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• 2018

Acute nicotine poisoning by liquid nicotine for electronic cigarettes is becoming an increasing problem worldwide. On the other hand, there are no regulations regarding its concentration, container or labelling in Korea. This is the first case of a cardiac arrest after liquid nicotine ingestion that was confirmed by plasma nicotine detection in Korea. A 34-year-old male was found with a cardiac arrest at home by the emergency medical services crew, and had a return of spontaneous circulation after 27 minutes of cardio-pulmonary resuscitation. The cause of his cardiac arrest was suspected to be acute nicotine poisoning by the ingestion of liquid nicotine. Toxicology analysis of the National Forensic Service confirmed plasma nicotine, and the pharmacokinetic estimated average concentration of plasma nicotine at the time of the cardiac arrest was 29.7 mg/L, a lethal dose. He was hospitalized for further treatment, but was discharged after 20 days without any improvement. Considering the strong toxicity of nicotine, appropriate policy decisions are required for sales and distribution.

• Proceedings of the Korean Vacuum Society Conference
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• 1997.07a
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• pp.173-176
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• 1997

A numerical analysis of the micro-discharge in an AC pplasma dispplay cell has been made using time-deppendent, 2-dimensional multi-fluid equations to understand the discharge pphysics of He-Xe discharge. The time deppendent distribution of the electron tempperature, densities of electrons, various ions and excited sppecies, and the effects fo the wall charge accumulated on the dielectric surface are obtained and comppared with the results of direct observation of time deppendent behavior of VUV and visible sppectra from single discharge cell observed using a gated, image intensified CCD to elucidate the discharge physics.