• 대한치과의사협회지
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• 제9권4호
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• pp.157-160
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• 1971

To compare the effects of various pulp capping agents that are usually applied to human pulp tissue, adult dogs were bred for a certain period and each capping agent was applied experimentally to pulp tissue after vital pulpotomy. Histological observations are as follows. 1) In comparison between methods of vital pulpotomy, one and two appointment method, different courses of healing were observed. In one appointment method, the granulation tissue formation at the amputation sur face of pulp tissue had a tendency to be transformed to scar tissue formation. In two appointment method, more transformation than that of one appointment method from scar tissue to dentin matrix formation were observed. 2) Histologic changes that have appeared in pulp tissue are a) fixation at outer layer b) degeneration at middle layer c) hyperemia and round cell infiltration at inner layer 3) With use of formocresol mixed zinc oxide powder in two appointment method complete formation of dentin matrix were observed. 4) Among the methods and aagents described above formocresol mixed zinc oxide powder in two appointment method appeared to be relatively effective.

• 한국재료학회지
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• 제13권11호
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• pp.711-716
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• 2003

Gate length, height, and silicide thickness have all been shrinking linearly as device density has progressively increased over the years. We investigated the effect of the cobalt diffusion during the silicide formation process on the 60$\AA$-thick gate oxide lying underneath the Ti/Co and Co/Ti bilayers. We prepared four different cobalt silicides, which have similar sheet resistance, made from the film structure of Co/Ti(interlayer), and Ti(capping layer)/Co, and peformed the current-voltage, time-to-break down, and capacitance-voltage measurements. Our result revealed that the cobalt silicide process without the Ti capping layer allowed cobalt atoms to diffuse into the upper interface of gate oxides. We propose that 100$\AA$-thick titanium interlayer may lessen the diffusion of cobalt to gate oxides in 1500-$\AA$ height polysilicon gates.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.15-16
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• 2006

The thermal stability of nickel silicide with compressively and tensilely stressed nitride capping layer has been investigated in this study. The Ni (10 nm) and Ni/Co/TiN (7/3/25 nm) structures were deposited on the p-type Si substrate. The stressed capping layer was deposited using plasma enhanced chemical vapor deposition (PECVD) after silicide formation by one-step rapid thermal process (RTP) at $500^{\circ}C$ for 30 sec. It was found that the thermal stability of nickel silicide depends on the stress induced by the nitride capping layer. In the case of Ni (10 nm) structure, the high compressive sample shows the best thermal stability, whereas in the case of Ni/Co/TiN (7/3/25 nm) structure, the high compressive sample shows the worst thermal stability.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권4호
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• pp.199-203
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• 2006

This paper presents an ASER (Accelerated Soft Error Rate) integral model. The model is based on the facts that the generated EHP/s(electron hole pairs) are diminished after some residual range of the incident alpha particle, where residual range is a function of the incident angle and the capping layer thickness over the semiconductor junction. The ASER is influenced by the flux of the alpha particles, the junction area ratio, the alpha particle incident angle when the critical charge is same as the collected charge, and the sizes of the alpha source and the chip. The model was examined with 8M static RAM samples. The measured ASER data showed good agreement with the calculated values using the model. The ASER decreased exponentially with respect to the operational voltage. As the capping layer thickness increases up to $16{\mu}m$, the ASER increases, and after that thickness, the ASER decreases. The ASER increased as the depth of BNW increased from $0{\mu}m\;to\;4{\mu}m$. and then saturated. The ASER decreased as the node capacitance increased from 2fF to 5fF.

• 한국농공학회논문집
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• 제56권3호
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• pp.11-17
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• 2014

We investigated the applicability of steel slag as a capping material in order to minimize phosphorus(P) release into seawater. Steel slag is a byproduct from the iron and steel industries and the use of steel slag has some advantages in respect of both cost and environmental concern. P removal by steel slag were studied in a batch system with respect to changes in contact time and initial concentration. Kinetic adsorption data were described well by pseudo 2nd order model, indicating rate limiting step for P adsorption to steel slag is chemical sorption. Equilibrium adsorption data fitted well to Langmuir isotherm model which describes for single layer adsorption. The maximum P adsorption capacity of steel slag was 7.134 mg-P/L. Increasing the depth of steel slag produced a positive effect on interruption of P release. More than 3 cm of steel slag was effective for blocking P release and 5 cm of steel slag was recommended as the depth for capping of P contaminated marine sediments. Increasing P concentration and flow rate had a negative effect on P removal ratio. It was concluded that the steel slag has a potential capping material for blocking P release from marine sediments.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2007년도 춘계학술대회
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• pp.193-198
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• 2007

The NiSi is very promising candidate for the metallization in 60nm CMOS process such as FUSI(fully silicided) gate and source/drain contact because it exhibits non-size dependent resistance, low silicon consumption and mid-gap workfunction. Ni film was first deposited by using ALD (atomic layer deposition) technique with Bis-Ni precursor and $H_2$ reactant gas at $220^{\circ}C$ with deposition rate of $1.25{\AA}/cycle$. The as-deposited Ni film exhibited a sheet resistance of $5{\Omega}/{\square}$. RTP (repaid thermal process) was then performed by varying temperature from $400^{\circ}C$ to $900^{\circ}C$ in $N_2$ ambient for the formation of NiSi. The process window temperature for the formation of low-resistance NiSi was estimated from $600^{\circ}C$ to $800^{\circ}C$ and from $700^{\circ}C$ to $800^{\circ}C$ with and without Ti capping layer. The respective sheet resistance of the films was changed to $2.5{\Omega}/{\square}$ and $3{\Omega}/{\square}$ after silicidation. This is because Ti capping layer increases reaction between Ni and Si and suppresses the oxidation and impurity incorporation into Ni film during silicidation process. The NiSi films were treated by additional thermal stress in a resistively heated furnace for test of thermal stability, showing that the film heat-treated at $800^{\circ}C$ was more stable than that at $700^{\circ}C$ due to better crystallinity.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.239-239
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• 2007

• 한국재료학회지
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• 제15권5호
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• pp.318-322
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• 2005

Ti-capped NiSi contacts were formed on $p^+/n$ junctions to improve the leakage problem and then Cu was deposited without removing the Ti-capping layer in an attempt to utilize as a diffusion barrier. The electrical characteristics of these $p^+/n$ diodes with Cu/Ti/NiSi electrodes were measured as a function of drive-in RTA(rapid-thermal annealing) and silicidation temperature and time. When drive-in annealed at $900^{\circ}C$, 10 sec. and silicided at $500^{\circ}C$, 100 sec., the diodes showed the most excellent I-V characteristics. Especially, the leakage current was $10^{-10}A$, much lower than reported data for diodes with NiSi contacts. However, when the $p^+/n$ diodes with Cu/Ti/NiSi contacts were furnace-annealed at $400^{\circ}C$ for 40 min., the leakage current increased by 4 orders. The FESEM and AES analysis revealed that the Ti-capping layer effectively prohibited the Cu diffusion, but was ineffective against the NiSi dissociation and consequent Ni diffusion.

• 반도체디스플레이기술학회지
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• 제10권1호
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• pp.57-61
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• 2011

To develop high efficiency crystalline solar cells, the rear surface passivation is very important. In this paper, $Al_2O_3$ films deposited by thermal ALD(atomic layer deposition) method were studied for rear surface passivation of crystalline solar cells and their passivation properties were evaluated. After the deposition of $Al_2O_3$ films on p-type Si wafers, the lifetime was increased very much due to the reduction of interface state density and the field effects of the negative fixed charge in the films. Also, optimum annealing condition and effects of SiNx capping layer were investigated. The best lifetime was obtained when the films were annealed at $400^{\circ}C$ for 15min. And the lifetime degradation of the $Al_2O_3$ films with SiNx capping layers was improved compared to those without the capping layers.

• 한국산학기술학회논문지
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• 제6권3호
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• pp.270-272
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• 2005

코발트 실리사이드는 낮은 전기 저항성 때문에 고효율 소자를 제조하는데 적합한 물질이다. 이는 전자소재가 소형화되면서 접촉저항과 혼합을 줄이기 위해 더욱 필요하게 되었다. 본 연구에서는 티타늄의 표면산화에 미치는 영향과, RTO 조건에서 온도에 따른 코발트 실리사이드 박막의 산화정도를 측정했다. 기질로서 p-형 실리콘웨이퍼를 사용하였고, 고속 열 가공을 통하여 박막을 가공하였다. 티타늄 층을 입혔을 때 산화충의 두께는 $500{\AA}$정도 성장하였다. 고속 열산화의 온도변화에 따라 산화막은 $550^{\circ}C\~700^{\circ}C$까지는 성장을 보였으나 $700^{\circ}C$이상에는 산화막 성장이 포화상태를 보였다.