다결정 실리콘 박막 위에 P이온 샤워 도핑 후 열처리 방법에 따르는 도펀트 활성화 및 결함 회복에 관한 효과

김동민,노재상,이기용,Kim, Dong-Min,Ro, Jae-Sang,Lee, Ki-Yong 한국전기화학회 2005 한국전기화학회지 Vol.8 No.1

Ion-Shower-Doping장비 및 $PH_/3M_2$혼합 가스를 사용하여 Phosphorous를 ELA방법으로 제조된 Poly-Si에 가속 전압 및 조사량을 변수로 이온 주입하였다. As-implanted된 시편의 결정도는 UV-transmittance spectroscopy를 사용하여 측정하였다. 이 때 UV-transmittance를 이용하여 측정한 값은 Raman spectroscopy를 이용해서 측정한 값과 서로 관련되어 있음을 알았다. 면 저항은 가속전압이 1kV에서 15kV까지 증가함에 따라 감소한다 그러나 가혹한 도핑조건하에서는 가속전압의 증가 시 면 저항이 증가한다. 이는 활성화 열처리 후 치유되지 않은 결함에 의해 전자가 포획되며 이에 따라 전하 운반자의 농도가 감소하는 때문이다. 활성화 열처리는 로열처리, RTA 열처리, ELA 열처리 등의 방법으로 수행하였고 열처리 방법에 따르는 도펀트의 활성화 및 결함의 회복의 거동을 연구하였다 Ion shower doping with a main ion source of $P_2H_x$ using a source gas mixture of $PH_3/H_2$ was conducted on excimer-laser-annealed (ELA) poly-Si.The crystallinity of the as-implanted samples was measured using a UV-transmittance. The measured value using UV-transmittance was found to correlate well with the one measured using Raman Spectroscopy. The sheet resistance decreases as the acceleration voltage increases from 1kV to 15kV at the moderate doping conditions. It, however, increases as the acceleration voltage increases under the severe doping conditions. The reduction in carrier concentration due to electron trapping at uncured damage after activation annealing seems to be responsible for the rise in sheet resistance. Three different annealing methods were investigated in terms of dopant-activation and damage-recovery, such as furnace annealing, excimer laser annealing, and rapid thermal annealing, respectively.

교번자속 인가에 의한 유기 반도체막의 어닐링 효과에 관한 연구

박재훈(Jae Hoon Park),최종선(Jong Sun Choi),이용수(Yong Soo Lee),노재상(Jae Sang Ro),김은석(Eun Seok Kim) 대한전기학회 2003 대한전기학회 학술대회 논문집 Vol.2003 No.7

초 저 에너지 이온주입으로 고 조사량 B 이온 주입된 실리콘의 Deactivation 현상

유승한,노재상,Yoo, Seung-Han,Ro, Jae-Sang 한국재료학회 2003 한국재료학회지 Vol.13 No.6

Shallow $p^{+}$ n junction was formed using a ULE(ultra low energy) implanter. Deactivation phenomena were investigated for the shallow source/drain junction based on measurements of post-annealing time and temperature following the rapid thermal annealing(RTA) treatments. We found that deactivation kinetics has two regimes such that the amount of deactivation increases exponentially with annealing temperature up to $850^{\circ}C$ and that it decreases linearly with the annealing temperature beyond that temperature. We believe that the first regime is kinetically limited while the second one is thermodynamically limited. We also observed "transient enhanced deactivation", an anomalous increase in sheet resistance during the early stage of annealing at temperatures higher than X$/^{\circ}C$. Activation energy for transient enhanced deactivation was measured to be 1.75-1.87 eV range, while that for normal deactivation was found to be between 3.49-3.69 eV.

전자재료 심포지엄 : CMOS Retrograde Well 제조시 MeV B 이온주입에 의한 Buried Layer 형성

장윤택,류한권,노재상 ( Yoon Taek Jang,Han Gwon Ryu,Jae Sang Ro ) 대한금속학회 1998 大韓金屬學會會報 Vol.11 No.5

라만 분석을 통한 비정질 실리콘 박막의 고온 고상 결정화 거동

홍원의(Won-Eui Hong),노재상(Jae-Sang Ro) 한국표면공학회 2010 한국표면공학회지 Vol.43 No.1

Solid phase crystallization (SPC) is a simple method in producing a polycrystalline phase by annealing amorphous silicon (a-Si) in a furnace environment. Main motivation of the crystallization technique is to fabricate low temperature polycrystalline silicon thin film transistors (LTPS-TFTs) on a thermally susceptible glass substrate. Studies on SPC have been naturally focused to the low temperature regime. Recently, fabrication of polycrystalline silicon (poly-Si) TFT circuits from a high temperature polycrystalline silicon process on steel foil substrates was reported. Solid phase crystallization of a-Si films proceeds by nucleation and growth. After nucleation polycrystalline phase is propagated via twin mediated growth mechanism. Elliptically shaped grains, therefore, contain intra-granular defects such as micro-twins. Both the intra-granular and the inter-granular defects reflect the crystallinity of SPC poly-Si. Crystallinity and SPC kinetics of high temperatures were compared to those of low temperatures using Raman analysis newly proposed in this study.

OLED 소자 제조를 위한 주울 가열 봉지 공정 시 도전층 구조에 따르는 열분포

장인구(Ingoo Jang),노재상(Jae-Sang Ro) 한국표면공학회 2013 한국표면공학회지 Vol.46 No.4

Encapsulation is required since organic materials used in OLED devices are fragile to water vapor and oxygen. Laser sealing method is currently used where IR laser is scanned along the glass-frit coated lines. Laser method is, however, not suitable to encapsulating large-sized glass substrate due to the nature of sequential scanning. In this work we propose a new method of encapsulation using Joule heating. Conductive layer is patterned along the sealing lines on which the glass frit is screen printed and sintered. Electric field is then applied to the conductive layer resulting in bonding both the panel glass and the encapsulation glass by melting glass-frit. In order to obtain uniform bonding the temperature of a conductive layer having a shape of closed loop should be uniform. In this work we conducted simulation for heat distribution according to the structure of a conductive layer used as a Joule-heat source. Uniform temperature was obtained with an error of 5% by optimizing the structure of a conductive layer. Based on the results of thermal simulations we concluded that Joule-heating induced encapsulation would be a good candidate for encapsulation method especially for large area glass substrate.

Mesh-type PECVD 방법으로 제조된 비정질 Si박막의 특성 및 레이저 결정화

한상용,최재식,김용수,박성계,노재상,김형준,Han Sang-Yong,Choi Jae-Sik,Kim Yong-Su,Park Sung-Gye,Ro Jae-Sang,Kim Hyoung-June 한국전기화학회 2000 한국전기화학회지 Vol.3 No.1

It is increasingly necessary to use poly-Si n's as high resolution and integration of Tn for LCD. Excimer Laser Crystallization (ELC) of a-Si is mainly used as a low temperature process. But the ELC method for the fabrication of poly-Si has the eruption problems associated with hydrogen in the a-Si film. So we need a dehydro-genation process additionally. Hydrogen in a-Si film can degrade the quality of poly-Si film and electrical properties of device due to the hydrogen eruption and voids which occur during the excimer laser annealing. In this study, we propose mesh-type PECVD as the a-Si film deposition method for achieving the low concentration hydrogen. Mesh-type PECVD was found to reduce the hydrogen content substantially. We could obtain a as-deposited a-Si film with hydrogen contents less than $1\%$ at $300^{\circ}C$. We also investigated the behavior by XeCl excimer laser annealing of a-Si fabricated by mesh-type PECVB. As a result, we were able to confirm the broad process window in contrast to the narrow process range typically obtained in ELC. Hydrogen eruption was not observed in poly-Si films after ELC These results suggests that mesh-type PECVD is a viable method to achieve the low hydrogen content a-Si and improve the process windows for ELC. poly-Si TR는 LCD의 고해상도화, 고집적화에 따라 그 요구가 점점 필요해지고 있다. 그러나 poly-Si의 제조를 위해 주로 사용하는 레이저 결정화 방법은 박막 내에 함유된 수소 때문에 별도의 탈수소 공정을 행하는 실정이다. 막내의 수소는 결정화 시 eruption과 void등의 생성으로 poly Si의 막 특성뿐 아니라 소자 특성에도 나쁜 영향을 미치게 된다. 본 연구에서는 전술한 문제점을 제어하기 위해 mesh-type PECVD를 제안하고 저수소화 박막 증착에 관한 연구를 수행하였다. 증착된 비정질 Si 박막은 $300^{\circ}C$ 이하의 온도에서도 $1 at\%$ 이하의 낮은 수소 함유량을 가진 것으로 조사되었다. mesh에 의한 이런 결과는 막내에 함유되는 수소를 효과적으로 제어하고 별도의 탈수소 공정을 배제하여 공정 감소의 효과를 갖는 장점이 있다. 또한 제조된 비정질 Si을 이용하여 XeCl 레이저 결정화하여 그 거동을 조사하였는데 일반적인 거동과 달리 매우 넓은 공정 영역을 갖고 있는 것을 확인할 수 있었다 또한, 수소에 의한 표면 거칠기 문제는 발견되지 않았으며 비교적 조대하고 균일한 결정립 분포를 하는 것으로 조사되었다 본 결과는 레이저 결정화 공정의 안정성에 기여하고 소자 특성 향상에도 기여할 것으로 기대된다

MeV Si 자기 이온주입된 단결정 Silicon내의 결함 거동

조남훈,장기완,서경수,이정용,노재상,Cho, Nam-Hoon,Jang, Ki-Wan,Suh, Kyung-Soo,Lee, Jeoung-Yong,Ro, Jae-Sang 한국재료학회 1996 한국재료학회지 Vol.6 No.7

본 연구에서는 MeV Si 자기 이온주업을 실시하여 주업원자와 모재 원자와의 화학적 영향이 배제된 결함 형성 거동을 관찰하였다. 자기 이온주업을 위하여 Tandem Accelerator가 사용되었고 1~3 MeV의 에너지 범위의 이온주입이 실시되었다. MeV 이온주입된 시편의 격자결함은 표면으로부터 고립된 $R_p$ 근처에 집중된 것이 관찰되었다. 주입에너지 변화에 따른 격자결함 생성 거동을 관찰하기 위하여 조사량을 $1{\times}10^{15}/cm^2$으로 고정하고 주입에너지를 1~3 MeV로 증가하였다. RBS 분석 결과 격자결함의 형성층 깊이는 에너지 증가에 따라 증가하였고 표면층에는 에너지 증가시 더욱 좋은 결정성을 유지하였다. 또한 주입에너지가 일정한 경우 조사량 증가시 $R_p$ 부근에 집중된 결함층의 농도는 증가하였으나 표면부근의 결함농도는 임계조사량 이상에서 포화되는 것이 관찰되었다. XTEM 분석 결과는 RBS의 결과와 잘 일치하였다. XTEM 관찰 결과 이온주업 상태의 결함층은 dark band의 형태로 관찰되었고 열처리시 이차결함은 이곳으로부터 생성되었다. 2MeV $Si^+$ 자기 이온주입시 이차결함이 형성되는 임계조사량은 $3{\times}10^{14}{\sim}5{\times}10^{14}/cm^2$ 사이로 관찰되었다. 열처리시 dark band의 하단부의 위치는 변화하지 않고 상단부만이 제거되었다. 실험을 통하여 얻은 결과들은 Monte-Carlo technique을 이용한 TRIM-code를 사용하여 해석하였다. SIMS 분석을 통하여 이차결함은 모재내에 존재하는 oxygen 불순물을 gettering함을 관찰하였다. In this study MeV Si self ion implantations were done to reveal the intrinsic behavior of defect formation by excluding the possibility of chemical interactions between substrate atoms and dopant ones. Self implantations were conducted using Tandem Accelerator with energy ranges from 1 to 3 MeV. Defect formation by high energy ion implantation has a significant characteristics in that the lattice damage is concentrated near Rp and isolated from the surface. In order to investigate the energy dependence on defect formation, implantation energies were varied from 1 to 3 MeV under a constant dose of $1{\times}10^{15}/cm^2$. RBS channe!ed spectra showed that the depth at which as-implanted damaged layer formed increases as energy increases and that near surface region maintains better crystallinity as energy increases. Cross sectional TEM results agree well with RBS ones. In a TEM image as-implanted damaged layer appears as a dark band, where secondary defects are formed upon annealing. In the case of 2 MeV $Si^+$ self implantation a critical dose for the secondary defect formation was found to be between $3{\times}10^{14}/cm^24$ and $5{\times}10^{14}/cm^2$. Upon annealing the upper layer of the dark band was removed while the bottom part of the dark band did not move. The observed defect behavior by TEM was interpreted by Monte Carlo computer simulations using TRIM-code. SIMS analyses indicated that the secondary defect formed after annealing gettered oxygen impurities existed in silicon.

고지방식이 비만마우스 모델에서 강지환(降脂丸)과 강지환(降脂丸)+가미소체환(加味消滯丸)의 비알콜성 지방간질환 개선효과 비교

장두현,정양삼,김종훈,김병출,석화준,유재상,구자룡,윤기현,조주흠,이혜림,노종성,윤호영,윤미정,신순식,Jang, Du Hyon,Jung, Yang Sam,Kim, Jong Hoon,Kim, Byeong Chul,Seok, Hoa Jun,Yoo, Jae Sang,Ku, Ja Ryong,Yoon, Ki Hyeon,Jo, Ju Heum,Lee, Hye Rim,Ro 대한한의학방제학회 2014 大韓韓醫學方劑學會誌 Vol.22 No.1

Objectives : This study investigated the improvement effects of Gangjihwan (DF) and combination of Gangjihwan and Gamisochehwan (GSH) on nonalcoholic fatty liver disease in a high fat diet-induced obese mouse model. Methods : Eight-week-old C57BL/6N mice were divided into five groups: a normal lean group given a standard diet, an obese control group given a high fat diet, and atorvastatin, DF, and DF+GSH groups given a high fat diet with atorvastatin (10 mg/kg), DF (40 mg/kg), and DF+GSH (80 mg/kg), respectively. After 8 weeks of treatment, body weight gain, blood lipid markers, ALT concentrations, liver weight and histology were examined. Results : 1. Body weight gain was significantly decreased in DF, DF+GSH and atorvastatin groups compared with control. The extent of decreases was eminent in DF+GSH group. 2. Circulating concentrations of total cholesterol, HDL-cholesterol and LDL-cholesterol were decreased in DF, DF+GSH and atorvastatin groups compared with control. The decreases were significant in DF+GSH and atorvastatin groups. 3. Liver weights were decreased in DF, DF+GSH and atorvastatin groups compared with control. In particular, liver weight was significantly reduced only in DF+GSH group. 4. Hepatic lipid accumulation was significantly decreased in DF, DF+GSH and atorvastatin groups compared with control, and the magnitude of which was more effective in DF+GSH group than in DF-only group. 5. Circulating ALT concentrations were decreased in DF, DF+GSH and atorvastatin compared with control, but ALS levels were significantly reduced only in DF+GSH group. Conclusions : In conclusion, these results suggest that DF decreases body weight gain, improves blood lipid metabolism, and reduces liver weight and hepatic lipid accumulation, contributing to the improvement of nonalcoholic fatty liver disease. In addition, these effects were more effective in DF+GSH combination group than in DF-only group.

비정질 실리콘의 결정화를 위한 줄 가열 유도 결정화 공정에 대한 열적 연구

김동현(Dong Hyun Kim),박승호(Seungho Park),홍원의(Won Eui Hong),노재상(Jae Sang Ro) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.5

대면적 비정질 실리콘 박막의 결정화는 평판 디스플레이 생산에 있어서 핵심 요소로 꼽힌다. 현재 다양한 결정화 기술들이 연구 되고 있으며 그 중 최근에 소개된 줄 가열 유도 결정화는 수십 마이크로초의 짧은 공정 시간, 대면적 결정화 그리고 국부적인 가열로 기판의 열변형 억제 등의 잇점으로 인해 AMOLED 제작에 있어서 기대되는 기술이다. 본 연구에서는 JIC 공정 중 상변화과정에서의 온도를 이론적으로 해석하고 이를 실험과 비교하였다. 이를 통하여 결정화 메커니즘을 결정하는 임계온도를 in-situ 실험과 수치해석을 통해 밝혀내었다. Large area crystallization of amorphous silicon thin-films on glass backplanes is one of key technologies in manufacturing flat displays. Among various crystallization technologies, the Joule induced crystallization (JIC) is recently introduced and considered as the highly promising one in the OLED fabrication industries, since the whole film of amorphous silicon on glass can be crystallized within tens of microseconds, minimizing the thermally and structurally harmful influence on the glass. In this study we have investigated the temperature variation during the phase transformation theoretically and experimentally. Temperatures critical to crystallization are clarified for both solid-solid and solid-liquid-solid transition, based on in-situ measurements of temperature and numerical analysis during the JIC process.