• Mass Spectrometry Letters
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• 제11권4호
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• pp.65-70
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• 2020

Despite its great success in the field of proteomics, mass spectrometry has limited use for determining structural details of peptides, proteins, and their assemblies. Emerging ion mobility spectrometry-mass spectrometry has enabled us to explore the conformational space of protein ions in the gas phase, and further combinations with the gas-phase ion spectroscopy and the collision-induced unfolding have extended its abilities to elucidating the secondary structure and local details of conformational transitions. This review will provide a brief introduction to the combined approaches of IMS-MS with gas-phase ion infrared spectroscopy or collision-induced unfolding and their most recent results that successfully revealed higher-order structural details.

• 대한치과보철학회지
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• 제33권2호
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• pp.354-357
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• 1995

The secondary ion of titanium from commercially pur titanium implant which installed at Rabbit tibia. Was analyzed by Secondary lon Mass Spectroscopy. And we detected about 3476 ppm ion from $10-50{\mu}m$ distance from interface.

• 한국진공학회지
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• 제10권3호
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• pp.328-334
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• 2001

초박막 게이트 유전막 및 비휘발성 기억소자의 게이트 유전막으로 연구되고 있는 NO/$N_2$O 질화산화막 및 재산화질화산화막의 특성을 D-SIMS(dynamic secondary ion mass spectrometry), ToF-SIMS(time-of-flight secondary ion mass spectrometry), XPS(x-ray Photoelectron spectroscopy)으로 조사하였다. 시료는 초기산화막 공정후에 NO 및 $N_2$O 열처리를 수행하였으며, 다시 재산화공정을 통하여 질화산화막내 질소의 재분포를 형성토록 하였다. D-SIMS 분석결과 질소의 중심은 초기산화막 계면에 존재하며 열처리 공정에서 NO에 비해서 $N_2$O의 경우 질소의 분포는 넓게 나타났다. 질화산화막내 존재하는 질소의 상태를 조사하기 위하여 ToF-SIMS 및 XPS 분석을 수행한 결과 SiON, $Si_2$NO의 결합이 주도적이며 D-SIMS에서 조사된 질소의 중심은 SiON 결합에 기인한 것으로 예상된다. 재산화막/실리콘 계면근처에 존재하는 질소는 $Si_2$NO 결합형태로 나타나며 이는 ToF-SIMS로 얻은 SiN 및 $Si_2$NO 결합종의 분포와 일치하였다.

• 한국재료학회지
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• 제11권1호
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• pp.55-60
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• 2001

고 에너지 (1.5 MeV) 이온 주입된 Boron의 농도와 silicon 기판의 초기 산소 농도의 변화에 따라 silicon기판에 형성된 결정 결함 및 금속 불순물의 Gettering 효율에 대하여 DLTS(Deep Level Transient Spectroscopy), SIMS(Secondary ion Mass Spectroscopy), BMD(Bulk Micro-Defect) analysis 및 TEM (Transmission Electron Microscopy)을 이용하여 연구하였다. 이온 주입 전후의 DLTS 결과를 확산로 및 RTA를 이용한 열처리 전후의 DLTS 결과와 비교할 때 이온 주입 전 시편에서 볼 수 있는 공공에 의한 깊은 준위는 열처리 온도의 증가에 따라 금속 불순물과 관련된 깊은 준위로 천이함을 알 수 있다. 또한 고온 열처리의 경우, 초기 산소 농도가 높을수록 깊은 준위의 농도가 감소함을 볼 때 초기 산소 농도가 높을 수록 gettering 효율 측면에서 유리한 것으로 사료된다

• 한국공작기계학회논문집
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• 제14권1호
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• pp.44-51
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• 2005

Material degradation is a multibillion-dollar problem which affects all the industries amongst others. The last decades have seen the development of newer and more effective techniques such as Focused-ion beam(FIB), Transmission electron microscopy(TEM), Secondary-ion mass spectroscopy(SIMS), auger electron spectroscopy(AES), X-ray Photoelectron spectroscopy(XPS) , Electrochemical impedance spectroscopy(EIS), Photo- stimulated luminescence spectroscopy(PSLS), etc. to study various forms of material degradation. These techniques are now used routinely to obtain information on the chemical state, depth profiling, composition, stress state, etc. to understand the degradation behavior. This paper describes the use of these techniques specifically applied to materials degradation and failure analysis.

• Journal of Korean Vacuum Science & Technology
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• 제2권2호
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• pp.118-121
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• 1998

Diisopropylselenide (DIPSe) is employed for the metalorganic vapor phase epitaxy (MOVPE) of ZnSe in order to eliminate premature gas phase reaction while maintaining negligible carbon incorporation and preserving relatively low growth temperature. In combination with dimethylzinc, single crystalline ZnSe layers were grown on GaAs at temperature around 450$^{\circ}C$. Secondary ion mass spectrometry showed a negligible carbon incorporation in ZnSe films grown from DIPSe even at high [Ⅵ]/[II] ratios, in contrast of a carbon concentration of 1021 cm-3 in ZnSe films grown from diallyselenide (DASe). Crystalline and interface quality are demonstrated by secondary electron microscopy, secondary ion mass spectroscopy and double crystal X-ray diffraction.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.91-94
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• 2008

Newly developed Atom Probe Tomography (APT) technique can provide the highest available spatial resolution, 3D tomography imaging and quantitative chemical analysis in a sub-nm scale. As a complementary technique to APT, Nano-secondary ion Mass Spectroscopy (SIMS) also provides the boron distribution in micro-scale. Therefore, the exact behavior of boron at either grain boundary or grain interior in steels can be investigated by the combination of APT and SIMS techniques from the sub-nanometer scale to the micrometer scale. The results obtained by both APT and SIMS revealed that the boron atoms were mainly segregated to the grain boundaries rather than to the grain interior in the steels containing 50ppm and 100ppm boron. It also found that carbon atoms were segregated at the boron enriched regions, which were thought to be retained austenite phase due to the chemical composition of carbon atoms.

• 한국재료학회지
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• 제25권9호
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• pp.497-502
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• 2015

The hardenability of boron steel specimens with different molybdenum and chromium contents was investigated using dilatometry and microstructural observations, and then was quantitatively measured at a critical cooling rate corresponding to 90 % martensite hardness obtained from a hardness distribution plotted as a function of cooling rate. Based on the results, the effect of an austenitizing temperature on the hardenability and tensile properties was discussed in terms of segregation and precipitation behavior of boron atoms at austenite grain boundaries. The molybdenum addition completely suppressed the formation of pro-eutectoid ferrite even at the slowest cooling rate of $0.2^{\circ}C/s$, while the chromium addition did at the cooling rates above $3^{\circ}C/s$. On the other hand, the hardenability of the molybdenum-added boron steel specimens decreased with an increasing austenitizing temperature. This is associated with the preferred precipitation of boron atoms since a considerable number of boron atoms could be concentrated along austenite grain boundaries by a non-equilibrium segregation mechanism. The secondary ion mass spectroscopy results showed that boron atoms were mostly segregated at austenite grain boundaries without noticeable precipitation at higher austenitization temperatures, while they formed as precipitates at lower austenitization temperatures, particularly in the molybdenum-added boron steel specimens.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.339.1-339.1
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• 2014

In this paper we studied the application of inter-poly dielectric as silicon dioxide-like film was deposited by the higher energy assisting deposition (HEAD) process the modified CCP process, which enables low temperature (LT) process and improving film density. In these experiments the relative hydrogen concentration of $SiO_2$-like films deposited on silicon substrate were analyzed by the secondary ion mass spectroscopy (SIMS) and it was shown that our lower hydrogenated oxide (LHO) film prepared by HEAD process with the precursor contained the siloxane species had lower hydrogen concentration, $8{\times}10{\cdot}^{22}cm{\cdot}^3$ than that of the commercial undoped silicon glass (USG) film ($1{\times}10{\cdot}^{21}cm{\cdot}^3$) prepared by the high density plasma-chemical vapor deposition (HDP-CVD). We consider that the LHO film deposited by HEAD process used as high performance material into Flash memory devices.

• 한국재료학회지
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• 제23권10호
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• pp.555-561
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• 2013

The hardenability of low-carbon boron steels with different molybdenum and chromium contents was investigated using dilatometry, microstructural observations and secondary ion mass spectroscopy (SIMS), and then discussed in terms of the segregation and precipitation behaviors of boron. The hardenability was quantitatively evaluated by a critical cooling rate obtained from the hardness distribution plotted as a function of cooling rate. It was found that the molybdenum addition was more effective than the chromium addition to increase the hardenability of boron steels, in contrast to boron-free steels. The addition of 0.2 wt.% molybdenum completely suppressed the formation of eutectoid ferrite, even at the slow cooling rate of $0.2^{\circ}C/s$, while the addition of 0.5 wt.% chromium did this at cooling rates above $3^{\circ}C/s$. The SIMS analysis results to observe the boron distribution at the austenite grain boundaries confirmed that the addition of 0.2 wt.% molybdenum effectively increased the hardenability of boron steels, as the boron atoms were significantly segregated to the austenite grain boundaries without the precipitation of borocarbide, thus retarding the austenite-to-ferrite transformation compared to the addition of 0.5 wt.% chromium. On the other hand, the synergistic effect of molybdenum and boron on the hardenability of boron steels could be explained from thermodynamic and kinetic perspectives.