• 제목/요약/키워드: Secondary Ion Mass Spectrometry

검색결과 163건 처리시간 0.04초

Chemical Imaging Analysis of the Micropatterns of Proteins and Cells Using Cluster Ion Beam-based Time-of-Flight Secondary Ion Mass Spectrometry and Principal Component Analysis

  • Shon, Hyun Kyong;Son, Jin Gyeong;Lee, Kyung-Bok;Kim, Jinmo;Kim, Myung Soo;Choi, Insung S.;Lee, Tae Geol
    • Bulletin of the Korean Chemical Society
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    • 제34권3호
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    • pp.815-819
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    • 2013
  • Micropatterns of streptavidin and human epidermal carcinoma A431 cells were successfully imaged, as received and without any labeling, using cluster $Au_3{^+}$ ion beam-based time-of-flight secondary ion mass spectrometry (TOF-SIMS) together with a principal component analysis (PCA). Three different analysis ion beams ($Ga^+$, $Au^+$ and $Au_3{^+}$) were compared to obtain label-free TOF-SIMS chemical images of micropatterns of streptavidin, which were subsequently used for generating cell patterns. The image of the total positive ions obtained by the $Au_3{^+}$ primary ion beam corresponded to the actual image of micropatterns of streptavidin, whereas the total positive-ion images by $Ga^+$ or $Au^+$ primary ion beams did not. A PCA of the TOF-SIMS spectra was initially performed to identify characteristic secondary ions of streptavidin. Chemical images of each characteristic ion were reconstructed from the raw data and used in the second PCA run, which resulted in a contrasted - and corrected - image of the micropatterns of streptavidin by the $Ga^+$ and $Au^+$ ion beams. The findings herein suggest that using cluster-ion analysis beams and multivariate data analysis for TOF-SIMS chemical imaging would be an effectual method for producing label-free chemical images of micropatterns of biomolecules, including proteins and cells.

Interaction between Oxygens and Secondary Defects Induced in Silicon by High Energy $B^+$Ion Implantation and Two-Step Annealing

  • Yoon, Sahng-Hyun;Jeon, Joon-Hyung;Kim, Kwang-Tea;Kim, Hyun-Hoo;Park, Chul-Hyun
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.185-186
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    • 2005
  • Intrinsic gettering is usually used to improve wafer quality which is an important factor for reliable ULSI devices. The two-step annealing method was adopted in order to investigate interactions between oxygens and secondary defects during oxygen precipitation process in lightly and heavily boron doped silicon wafers with high energy $^{11}B^+$ ion implantation. Secondary defects were inspected nearby the projected range by high resolution transmission electron microscopy. Oxygen pileup was measured in the vicinity of the projected range by secondary ion mass spectrometry for heavily boron doped silicon wafers.

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전하트랩형 NVSM의 게이트 유전막을 위한 질화산화막의 재산화특성에 관한 연구 (Characteristics of reoxidation of nitried oxide for gate dielectric of charge trapping NVSM)

  • 이상은;한태현;서광열
    • 한국결정성장학회지
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    • 제11권5호
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    • pp.224-230
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    • 2001
  • 초박막 게이트 유전막 및 비휘발성 기억소자의 게이트 유전막으로 연구되고 있는 $NO/N_2O$ 열처리된 재산화 질화산 화막의 특성을 D-SIMS(Dynamic Secondary Ion Mass Spectrometry), ToF-SIMS(Time-of-Flight Secondary Ion Mass Spectrometry), AES(Auger Electron Spectroscopy)으로 조사하였다. 시료는 초기산화막 공정후에 NO 및 $N_2O$ 열처리를 수행하였으며, 다시 재산화공정을 통하여 질화산화막내 질소의 재분포를 형성토록하였다. 재산화에 있어서 습식산화시 공정에 사용된 수소에 의한 영향으로 계면 근처에 축적된 질소가 Si≡N 결합을 쉽게 이탈함에 따라 방출이 촉진되어 건식산화에 비하여 질소의 감소가 더욱 두드러지게 나타났다. 재산화에 따른 질화산화막내 질소의 거동은 외부로의 방출과 기판으로의 확산이 동시에 나타난다. 재산화후 질화산화막내 축적된 질소의 결합종을 분석한 결과, 초기산화막 계면근처의 질소는 SiON의 결합종이 주도적으로 나타나는 반면 재산화 후 새롭게 형성된 $Si-SiO_2$ 계면근처로 확산한 질소는 $Si_2NO$ 결합종이 주로 검출된다. SiON에 의한 질소의 미결합손과 $Si_2$NO에 의한 실리콘의 미겨랍손은 기억특성에 기여하는 결함을 포함하기 때문에 재산화 질화산화막내 존재하는 SiON과 $Si_2$NO 결합종은 모두 전하트랩의 기원과 관련된 결합상태로 예상된다.

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MOVPE of ZnSe with DIPSe and DMZn

  • Soo, Huh-Jeung;Ok, Lim-Jeong
    • 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.

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Organic matrix-free imaging mass spectrometry

  • Kim, Eunjin;Kim, Jisu;Choi, Inseong;Lee, Jeongwook;Yeo, Woon-Seok
    • BMB Reports
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    • 제53권7호
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    • pp.349-356
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    • 2020
  • Mass spectrometry (MS) is an ideal tool for analyzing multiple types of (bio)molecular information simultaneously in complex biological systems. In addition, MS provides structural information on targets, and can easily discriminate between true analytes and background. Therefore, imaging mass spectrometry (IMS) enables not only visualization of tissues to give positional information on targets but also allows for molecular analysis of targets by affording the molecular weights. Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS is particularly effective and is generally used for IMS. However, the requirement for an organic matrix raises several limitations that get in the way of accurate and reliable images and hampers imaging of small molecules such as drugs and their metabolites. To overcome these problems, various organic matrix-free LDI IMS systems have been developed, mostly utilizing nanostructured surfaces and inorganic nanoparticles as an alternative to the organic matrix. This minireview highlights and focuses on the progress in organic matrix-free LDI IMS and briefly discusses the use of other IMS techniques such as desorption electrospray ionization, laser ablation electrospray ionization, and secondary ion mass spectrometry.

초기 산소 농도가 고에너지 이온 주입시 발생하는 산소 축적 및 불순물 확산에 미치는 영향 (Effcets of Initial Oxygen Concentration on Oxygen Pileup and the Diffusion of Impurities after High-energy Ion Impaltation)

  • 고봉균;곽계달
    • 전자공학회논문지D
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    • 제36D권4호
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    • pp.48-56
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    • 1999
  • 본 논문에서는 초기 산소 농도가 고에너지 이온 주입시 결정 격자 손상에 의해 발생하는 산소 축적(pileup) 현상 및 주입된 불순물의 확산에 미치는 영향을 실험적으로 고찰하였다. 초기 산소 농도가 11.5, 15.5 ppma인 p-type (100)실리콘 웨이퍼에 \sup 11\B\sup +\ \sup 31\P\sup +\ 이온을 각각 1.2 MeV, 2.2 MeV 의 에너지로 1×10\sup 15\cm\sup 2\ 주입하고, 700℃(20시간)+1000℃(10시간)의 2단계 열처리를 거치 후 주입된 불순물 및 산소 농도의 분포를 이차이온질량분석기 (Secondary Ion Mass Spectrometry, SIMS)로 관찰하였으며 잔류 2차 결함의 분포는 투과전자현미경(Transmission Electron Microscopy, TEM)으로 관찰하였다. SIMS 측정 결과 산소의 축적이 {{{{ { R}_{ } }}}}\sub p\(projected range) 부근에서 관찰되었으며 열처리 후에도 상당한 양의 2차 결합 띠가 {{{{ { R}_{ } }}}}\sub p\부근에서 관찰되는 것으로 보아 2차 결함에 의해 산소가 포획되었음을 알 수 있다. 또한 붕소와 인의 확산은 웨이퍼의 초기 산소 농도가 클수록 벌크 방향으로의 확산이 증대되는 현상을 볼 수 있었다.

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