고밀도 평판형 유도결합 BCl₃/SF₆ 플라즈마를 이용한 GaAs/AlGaAs와 InGaP 반도체의 선택적 식각에 관한 연구

유승열,류현우,임완태,이제원,조관식,전민현,송한정,이봉주,고종수,고정상,Yoo Seungryul,Ryu Hyunwoo,Lim Wantae,Lee Jewon,Cho Guan Sik,Jeon Minhyon,Song Hanjung,Lee BongJu,Ko Jong Soo,Go Jeung Sang,Pearton S. J. 한국재료학회 2005 한국재료학회지 Vol.15 No.3

We investigated selective dry etching of GaAs over AlGaAs and InGaP in high density planar inductively coupled $BCl_3/SF_6$ plasmas. The process parameters were ICP source power (0-500 W), RE chuck power (0-30W) and gas composition $(60-100\%\;BCl_3\;in\;BCl_3/SF_6)$. The process results were characterized in terms of etch rate, selectivities of GaAs over AlGaAs and InGaP, surface morphology, surface roughness and residues after etching. $BCl_3/SF_6$ selective etching of GaAs showed quite good results in this study. Selectivities of GaAs $(GaAs:AlGaAs\~36:1,\;GaAs:InGaP\~45:1)$ were superior at $18BCl_3/2SF_6$, 20 W RF chuck power, 300 W ICP source power and 7.5 mTorr. Addition of $(5-15\%)SF_6\;to\;BCl_3$ produced relatively high selectivities of GaAs over AlGaAs and InGaP during etching due to decrease of etch rates of AlGaAs and InGaP (boiling points of etch products: $AlF_3\~1300^{\circ}C,\;InF_3>1200^{\circ}C$ at atmosphere) at the condition. SEM and AFM data showed slightly sloped sidewall and somewhat rough surface$(RMS\~9nm)$. XPS study on the surface of processed GaAs proved a very clean surface after dry etching. It shows that planar inductively coupled $BCl_3/SF_6$ plasmas could be a good candidate for selective dry etching of GaAs over AlGaAs and InGaP.

솔레노이드의 고속 동작을 위한 모델링 및 제어

유승열,신동훈 한국반도체디스플레이기술학회 2011 반도체디스플레이기술학회지 Vol.10 No.4

Electronics in modern life have become more miniaturized and precise and new technology of electronic components has made these trends possible. The explosive demand of electronic components needs more high-speed and accurate performance of manufacturing processes. For high-speed actuation, solenoids, voice coil motors and piezo motors have been used. A solenoid actuator characterized by low price, available small size, and convenience is one of the main components of production equipments requiring compact and high-speed actuators. Since these actuators show millisecond order responsiveness, the improvement of 1~2msec is very important in industrial applications. In this paper, the mathematical model of the solenoid is formulated and simulated using SIMULINK^®. To verify the model, the responses for step input with open-loop control is obtained and compared with the simulation result. In order to improve the responsiveness, Hold voltage method is introduced and optimal value between spring constant and hold voltage is suggested.

Optimal Design of Non-Contact Thrust Bearing Using Permanent Magnet Rings

유승열,김우연,김승종,이욱련,배용채,노명규 한국정밀공학회 2011 International Journal of Precision Engineering and Vol. No.

This paper describes an optimal design process of a permanent-magnet thrust bearing. The bearing consists of two sets of permanent magnet rings. One set is located inside the other. An axial displacement between the two sets creates an axial force, thereby achieving a thrust bearing function. In order to obtain an optimal design of the bearing where the required load capacity of bearing is achieved with the least magnet volume, we derived analytical design equations based on the equivalent current sheet (ECS) method. We considered two types of magnet arrays: axial arrays and Halbach arrays. Optimization is carried out for these two types. The results show that the Halbach array can achieve the load capacity requirement with smaller magnet volume than the axial array. We also found that there exists an optimal axial separation of rings for the axial array. The efficacy of the ECS method is verified against the results from three-dimensional finite element analyses and experiments. It is found that the Halbach array is more sensitive to the underlying assumptions of ECS method than the axial array.

㈜모바일에코 - 사물통신용 IoT 통신 단말 및 IoT 서비스

유승열 한국전자파학회 2019 전자파기술 Vol.30 No.3

금속판재 적층을 이용한 쾌속금형 제작기술 개발

유승열 한국기술교육대학교 2006 論文集 Vol.13 No.1

The design and fabrication of dies and molds used in manufacturing operations represents one of the most time consuming and costly phases in the development of new products. New realities of the product market require faster product development and reduced time to market. To reduce the time and cost of the product development and manufacturing processes, the new technologies of Rapid Prototyping (RP) and Rapid Tooling (RT), which have been developed over the last two decades, are revolutionizing manufacturing development. One type of RT technology, which is the focus of this paper, is Profiled Edge Laminate (PEL) tooling. To facilitate adoption of the PEL method by industry, a complete tooling design process has been developed. PEL tooling is a laminated tooling method involving the assembly of an array of laminations whose top edges are simultaneously profiled and beveled based on a CAD model of the intended tool surface. The main goal of this research is to develop an advanced design process for PEL Tooling, that is, the required synthesis and analysis tools, and methodologies for designing PEL tools. The advanced PEL Tooling design process consists of slicing, simulation, and fabrication processes. The resulting design process is demonstrated by completely designing and fabricating a simple industrial PEL tool based on a CAD part shape.

"동의보감(東醫寶鑑)" "담음문(痰飮門)"의 병증(病症)에 따른 처방(處方) 고찰(考察)

유승열,국윤범,You, Seung-Yeol,Kook, Yoon-Bum 대한한의학방제학회 2011 大韓韓醫學方劑學會誌 Vol.19 No.1

Objectives : This study was performed to investigate 93 prescriptions which are all affiliated Phlegm-Fluid Substances chapter depending on Symptoms in Dongeuibogam. Methods : The following conclusions are reached through investigations on the applications of prescriptions which are all affiliated Phlegm-Fluid Substances chapter Depending on Symptoms in Dongeuibogam. Results : 1. Fluid detention disease article represents that Byukeum(癖飮), Hyuneum(懸飮) and Yueum(流飮) have the same treat criteria, in effect, there is not any problem left in case it is reached fluid detention disease is not 8 but 6. 2. Strong water-utilization herbs can be mainly used in treating Fluid detention disease, eliminating phlegm warm herbs are almost used two times more than eliminating phlegm cold herbs in eliminating phlegm disease. 3. Arisamatis Rhizoma is only used by itself in Chongmongseok-hwan, the others are used at the same time with Pinelliae Rhizoma. As a result of this, Arisamatis Rhizoma has an effects on eliminating Wind relative dusease but eliminating phlegm disease which can cause upper body phlegm disease. 4. Fritillariae Cirrhosae Bulbus and Tricosanthis Radix are able to get rid of obstinate phlegm-Fluid disease in eliminating phlegm cold herbs. 5. Gamisachil-tang and Gamieejin-tang which are located in throat chapter are more proper prescriptions to treat phlegm at throat than Gwache-san or Jeoljehwadam-hwan which is located in Phlegm-Fluid Substances chapter in Dongeuibogam. 6. Glycyrrhizae Radix is used 46 times(49%) at total 93 prescriptions in eliminating phlegm disease herbs. It seems to be needed more study whether Glycyrrhizae Radix can control the Phlegm-Fluid disease or not. Conclusions : The 93 prescriptions for eliminating Phlegm-Fluid Substances in Dongeuibogam are mainly composed of Sobanha-tang, Eejin-tang and Baeksang-hwan, etc.

CO₂플라즈마를 이용한 카본 분체 친수처리

유승열,석동찬,정용호 한국진공학회 2021 한국진공학회 학술발표회초록집 Vol.2021 No.2

카본 분체는 표면 기능기가 거의 존재하지 않으며, 대부분 C-C bonds 로 인해 낮은 surface energy를 가지고 있어 wetting이 어렵다. 카본 분체는 표면의 카본 기가 산소 관련 라디칼과 결합하여 C-O, C=O, COOH등의 기능기를 형성하면서 친수화 되므로, C, O가 포함된 CO₂gas를 해리 시키면 친수처리 할 수 있다. 적용된 전극은 직렬로 연결된 stacked DBD 전극을 사용하였고[1], QMS와 OES로 방전부산물을 측정하였다[2]. 플라즈마 처리된 카본 분체는 표면의 COOH 기능기가 증가하였고, SEM, EDS, XPS, Washburn method를 이용한 powder wettability, BET, 분체저항 및 수분산후 충분히 속도 비교로 친수처리 됨을 확인하였다.

알레르기성 비염 환자의 피부반응검사 및 RAST 검사의 비교

유승열,홍승인,김성완,이성만,김광일,유성근 대한이비인후과학회 1991 대한이비인후과학회지 두경부외과학 Vol.34 No.6

전자부품의 고속 외관검사를 위한 시스템 설계

유승열 한국반도체디스플레이기술학회 2012 반도체디스플레이기술학회지 Vol.11 No.3

Electronics in modern lives have become more miniaturized and precise. Multi Layered Ceramic Capacitor (MLCC) occupies 50% of electronic components consisting of electronics. This high volume of the production needs high speed and more precise machine performances. The dominate parts of the production equipments are the module transporting components and the visual inspection module. Most visual inspection has been off-line because of the image processing time. In this paper, a new image processing method is proposed to reduce thousands of matrix calculation for image processing and realize on-line high speed inspection.

동의보감(東醫寶鑑) 중 보중익기탕(補中益氣湯)의 임상응용(臨床應用) 연구(硏究) - 문헌고찰 및 활용성을 중심으로 -

유승열,임영환,국윤범,You, Seung-Yeol,Lim, Young-Hwan,Kook, Yoon-Bum 대한한의학방제학회 2009 大韓韓醫學方劑學會誌 Vol.17 No.1

To beef up natural immunity, we have used Bojoongikgitang which has been known to treat enervation in the oriental medicine. This study is analyzed out structure material and the chief virtue of a prescription through Literature Study on Bojoongikgitang and Clinical Application. And this study is investigated to make sure of the necessity and additional symptoms in using Bojoongikgitang. The results are as follows : 1. It is regarded that the structure materials of Bojoongikgitang consist of Astragali Radix one jeon(錢) five poon(分), Ginseng Radix, Atractylodis Macrocephalae Rhizoma, Glycyrrhizae Radix one jeon for each, Citri Pericarpium, Angelicae Gigantis Radix five poon for each, Cimicifugae Rhizoma, Bupleuri Radix three poon for each. 2. The necessity symptoms in using Bojoongikgitang are a pale complexion, drowsy eyes(目無精光), vigorless, lethargy, sluggish talk. 3. The fittest prescriptions prior to the necessity symptoms in using Bojoongikgitang are Bojoongikgitang added Paeoniae Radix Alba, Scutellariae Radix in fever, exterior heat, mild fever, Bojoongikgitang added Ephedrae Radix, Tritici Fructus Levis, Aconiti Iateralis Preparata Radix in spontaneous sweating, spontaneous sweating by yang deficiency, Bojoongikgitang added Paeoniae Radix Alba, Scutellariae Radix in feeling the pulse like a flood, largeness and weakness, scatter and largeness, flood and largeness for diagnosis respectively. Bojoongikgitang Entering the heart channel by culturing the blood prescription in vexation, vexation and anxiety, Soongihwajoongtang in headache, DossiBojoongikgitang in rigor, Bojoongikgitang annexed Saengmaecsan in thirst, Daninsamtang or Jojoongikgitang in asthma, asthma by congestion of the upwardness, Eeegongsan in light eating, eschewing food, losing one's appetite, Ikweeseungyangtang in deficiency failing to control blood and blood collapsey. 4. To treat a functional disease is superior to organic one in using Bojoongikgitang.