• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1327-1329
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• 1998

It is very important to select superior inter-layer PMD(Pre Metal Dielectric) materials which can act as penetration barrier to various impurities created by CMP processes. In this paper, hot carrier degradation and device characteristics were studied with material variation of PMD-1 layers, which were split by LP-TEOS, SR-Oxide, PE-Oxynitride, PE-Nitride, PE-TEOS films. It was observed that the oxynitride and nitride using plasma was greatly decreased in hot carrier effect in comparison with silicon oxide. Consequently, silicon oxide turned out to be a better PMD-1 material than PE-oxynitride and PE-nitride. Also, LP-TEOS film was the best PMD-1 material Among the silicon oxides.

• 한국철도학회논문집
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• 제9권3호
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• pp.305-312
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• 2006

Gravel ballasted tracks are used as a basic structure for the domestic railway tracks. However, such kind of tracks has few disadvantages with service life of the structure, such as rapid deterioration of the tracks. Due to this reason, there is a need to develop low maintenance track to improve the service life of the conventional line tracks. CMP paved tacks are one of the kind of concrete tracks those were manufactured by using the prepacked concrete techniques. The purpose to develop paved tracks is to reduce the maintenance cost. The most important controlling factors to design the paved tracks are surrounding environmental condition and repeated train loading. In this study, in order to investigate the deformation characteristics such as displacement, earth pressure, strain ratio, and crack along the repeated loading cycle, cyclic loading test through real scale model was carried out.

• 한국시뮬레이션학회논문지
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• 제11권1호
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• pp.23-30
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• 2002

An STI(Shallow Trench Isolation) by using a CMP(Chemical Mechanical Polishing) process has been one of the key issues in the device isolation[1] In this paper we fabricated N, P-MOSFEET tall analyse hump characteristics in various rounding oxdation thickness(ex : Skip, 500, 800, 1000$\AA$). As a result we found that hump occurred at STI channel edge region by field oxide recess. and boron segregation(early turn on due to boron segregatiorn at channel edge). Therefore we improved that hump occurrence by increased oxidation thickness, and control field oxide recess( 20nm), wet oxidation etch time(19HF,30sec), STI nitride wet cleaning time(99HF, 60sec+P 90min) and fate pre-oxidation cleaning time (U10min+19HF, 60sec) to prevent hump occurring at STI channel edge.

• Korean Journal of Radiology
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• 제22권12호
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• pp.1996-2005
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• 2021

Objective: To investigate the multidetector computed tomography (MDCT) features of fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC) with germline or somatic mutations, and compare them with those of papillary type II RCC (pRCC type II). Materials and Methods: A total of 24 patients (mean ± standard deviation, 40.4 ± 14.7 years) with pathologically confirmed FH-deficient RCC (15 with germline and 9 with somatic mutations) and 54 patients (58.6 ± 12.6 years) with pRCC type II were enrolled. The MDCT features were retrospectively reviewed and compared between the two entities and mutation subgroups, and were correlated with the clinicopathological findings. Results: All the lesions were unilateral and single. Compared with pRCC type II, FH-deficient RCC was more prevalent among younger patients (40.4 ± 14.7 vs. 58.6 ± 12.6, p < 0.001) and tended to be larger (8.1 ± 4.1 vs. 5.4 ± 3.2, p = 0.002). Cystic solid patterns were more common in FH-deficient RCC (20/24 vs. 16/54, p < 0.001), with 16 of the 20 (80.0%) cystic solid tumors having showed typical polycystic and thin smooth walls and/or septa, with an eccentric solid component. Lymph node (16/24 vs. 16/54, p = 0.003) and distant (11/24 vs. 3/54, p < 0.001) metastases were more frequent in FH-deficient RCC. FH-deficient RCC and pRCC type II showed similar attenuation in the unenhanced phase. The attenuation in the corticomedullary phase (CMP) (76.3% ± 25.0% vs. 60.2 ± 23.6, p = 0.008) and nephrographic phase (NP) (87.7 ± 20.5, vs. 71.2 ± 23.9, p = 0.004), absolute enhancement in CMP (39.0 ± 24.8 vs. 27.1 ± 22.7, p = 0.001) and NP (50.5 ± 20.5 vs. 38.2 ± 21.9, p = 0.001), and relative enhancement ratio to the renal cortex in CMP (0.35 ± 0.26 vs. 0.24 ± 0.19, p = 0.001) and NP (0.43 ± 0.24 vs. 0.29 ± 0.19, p < 0.001) were significantly higher in FH-deficient RCC. No significant difference was found between the FH germline and somatic mutation subgroups in any of the parameters. Conclusion: The MDCT features of FH-deficient RCC were different from those of pRCC type II, whereas there was no statistical difference between the germline and somatic mutation subgroups. A kidney mass with a cystic solid pattern and metastatic tendency, especially in young patients, should be considered for FH-deficient RCC.

• 지질공학
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• 제7권3호
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• pp.161-171
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• 1997

토공사의 안전시공과 품질향상을 위해서는 지반의 지질구조 및 특성에 대한 정확한 정보의 획득이 무엇보다 중요하다. 지하레이더 탐사법은 수~수십 m 이내의 얕은 심도 지반을 조사할수 있는 간편한 지구물리탐사법의 하나이다. 본 연구는 토공사의 주요한 관심 대상인 지질 경계면 추정에 지하레이데 탐사법을 적용한 사례에 관한 것이다. 탐사지역의 기반암은 안산암이며, 풍화토층, 풍화암층, 연암층 등으로 구성되어 있음이 시추조사 결과로 알려졌다. 여기에 지하레이더 탐사를 실시하여 이들 지질 경계면의 심도를 추정하였다. 지질 경계면 심도를 추정하기 위해서는 지하 매질에서의 전자기파 속도를 분석하여야 하는데, 본 연구에서는 공통 중간점 (CMP, Common Mid-Point) 방법으로 전자기파 평균 속도 0.096m/ns를 구하여 자료를 처리하였다. 이렇게 추정된 심도와 시추조사 결과가 거의 일치하고 있는 점을 확인하였다. 또한 시추조사로는 밝히지 못했던, 연암층 상부경계에서의 차별풍화로 인한 지층의 기복을 확인하였다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (2)
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• pp.674-676
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• 1998

소자가 sub-quarter um급으로 축소됨에 따라 STI(Shallow Trench Isolation) 기술은 고 집적도의 ULSI 구현에 있어서 중요한 격리 방법으로 많이 사용되고 있다. 현재의 STI 기술은 주로 실리콘 기판을 식각 후 절연물질로 빈 공백이 없이 채우는 (void-free gap filling) 방법 [1,2]과 절연물질을 다시 표면 근처까지 CMP(Chemical Mechnical Polishing)로 etchback하여 평탄화를 하는 방법이 주요한 기술이 되고 있다. 또한 STI 구조로된 격리구조에서 만들어진 MOSFET의 전기적인 특성은 트랜치 격리의 상부 부분의 형태와 gap-filling 물질에 따라 큰 영향을 받게된다. 따라서 본 논문에서는 STI 구조로 만들어진 격리 구조에서 MOSFET의 hump 특성에 관해 연구하였다. 그 결과 hump는 STI 모서리에서 필드 옥사이드의 recess에 의한 모서리 부분에서의 전계 집중과 boron의 segration에 기인한 농도 감소로 인해 hump가 발생하는 것으로 나타났다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.544-544
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• 2008

Metal-CMP 공정시 높은 압력을 가해 줌으로 인하여 금속배선의 디싱 현상과 에로젼 현상이 발생하고 다공성의 하부층에 균열이 생기는 문제점을 개선하고자, 낮은 하력에서 금속막의 광역 평탄화를 이룰 수 있는 ECMP(Electrochemical Chemical Mechanical Polishing)가 생겨나게 되었다. 본 논문에서는 다양한 전해액의 전류-전압 특성 곡선을 비교 분석하여, 패시베이션막이 형성되는 곳을 알 수 있었고, CV와 LSV 법을 통해 전기화학적인 특성을 고찰하였다.

• 한국전기전자재료학회논문지
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• 제20권3호
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• pp.234-239
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• 2007

This paper describes the TiW ohmic contact characteristics under the surface treatment of the polycrystalline 3C-SiC thin film grown on $SiO_2/Si(100)$ wafers by APCVD. The poly 3C-SiC surface was polished by using CMP(chemical mechanical polishing) process and then oxidized by wet-oxidation process, and finally removed SiC oxide layers. A TiW thin film as a metalization process was deposited on the surface treated poly 3C-SiC layer and was annealed through a RTA(rapid thermal annealing) process. TiW/poly 3C-SiC was investigated to get mechanical, physical, and electrical characteristics using SEM, XRD, XPS, AFM, optical microscope, I-V characteristic, and four-point probe, respectively. Contact resistivity of the surface treated 3C-SiC was measured as the lowest $1.2{\times}10^{-5}{\Omega}cm^2$ at $900^{\circ}C$ for 45 sec. Therefore, the surface treatments of poly 3C-SiC are necessary to get better contact resistance for extreme environment MEMS applications.

• 한국재료학회지
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• 제9권2호
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• pp.124-131
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• 1999

Copper film, which is expected to be used as interconnection material for 1 giga DRAM integrated circuits was deposited on hole and trench patterns by Metal Organic Chemical Vapor Deposition(MOCVD) method. After a reflow process, contact and L/S patterns were filled by copper and the characteristics of the Cu reflow process were investigated. When deposited Cu films were reflowed, grain growth and agglomeration of Cu have occurred in surfaces and inner parts of patterns as well as complete filling in patterns. Also Cu thin oxide layers were formed on the surface of Cu films reflowed in $O_2$ambient. Agglomeration and oxidation of Cu had bad influence on the electrical properties of Cu films especially, therefore, their removal and prevention were studied simultaneously. As a pattern size is decreased, preferential reflow takes place inside the patterns and this makes advantages in filling patterns of deep submicron size completely. With Cu reflow process, we could fill the patterns with the size of deep sub-micron and it is expected that Cu reflow process could meet the conditions of excellent interconnection for 1 giga DRAM device when it is combined with Cu MOCVD and CMP process.

• 한국결정성장학회지
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• 제28권1호
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• pp.51-56
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• 2018

PVT법으로 성장된 AlN 단결정의 표면 평탄화 최적화 하기 위하여 기계적 연마 후 $SiO_2$ slurry를 이용한 CMP 공정을 진행하였고 이에 따른 표면 형상, slurry 변화에 따른 가공 특성을 분석하였다. Slurry의 pH가 표면 연마 과정에 미치는 영향을 알아보기 위해 $SiO_2$ slurry의 pH를 조절하였으며, 제타전위측정기를 통해 각각의 pH에 따른 zeta potential의 영향과 MRR(material removal rate) 결과를 비교하였으며, 최종적으로 원자간력 현미경(atomic force microscope)을 이용한 표면 거칠기 RMS(0.2 nm)를 얻을 수 있었다.