XRD 패턴에 따른 유무기 복합화합물의 유전특성

오데레사,김경식 제주대학교 공과대학 첨단기술연구소 2006 尖端技術硏究所論文集 Vol.17 No.1

This paper reports the correlation between dielectric constant and degree of amorphism of the hybrid type Si-O-C thin films. Si-O-C thin films were deposited by high density plasma chemical vapor deposition using bistrimethyl-silylmethane (BTMSM, H9C3-Si-CH2-Si-C3H9) and oxygen precursors with various flow rate ratio. As-deposited film and annealed films at 400℃ were analyzed by XRD. The Si-O-C thin films were amorphous from XRD patterns. For quantitative analysis, the diffraction pattern of the samples was transformed to radial distribution function by Fourier analysis, and then compared with each other. The degree of amorphism of annealed films was higher than that of as-deposited ones. The dielectric constant varied in accordance with flow rate ratio of precursors. The lowest dielectric constant was obtained from the as-deposited film which has the highest degree of amorphism after annealing.

반도체 절연박막의 두께변화와 결정성에 대한 누설전류의 의존성

오데레사(Oh, Teresa) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.12

디스플레이를 위한 반도체 절연막으로 적합한 SiOC 박막의 특성을 살펴보기 위해서 스퍼터를 이용한 SiOC 박막을 증착하고 전기적인 특성을 조사하였다. SiOC 박막의 절연성은 열처리 온도에 따라서도 달라졌으며, 100도에서 열처리한 박 막의 두께는 증가하고 굴절률은 감소하였으며, XRD의 비정질 특성이 높아지고, 커패시턴스의 감소와 누설전류가 감소하는 특성이 관찰되었다. SiOC 박막의 누설전류 감소의 특성은 절연막으로서의 특성이 개선되고 있다는 것을 의미하며, 두께의 증가현상 또한 누설전류가 감소할 수 있는 조건을 잘 만들고 있었다. 분극의 감소에 의한 비정질의 특성은 SiOC박막을 구성 하고 있는 원자 간의 배열이 불규칙적으로 변하고 원자 사이의 결합길이가 최대한 길어지면서 이루어졌기 때문이며, 따라서 두께가 증가하였다. 100도에서 열처리 한 박막에서 두께가 증가하였으며, 누설전류가 감소하였다. 스퍼터에 의한 SiOC 박막 의 100도 온도에 의한 극적인 누설전류의 감소는 저온공정이 필수적인 디스플레이용 반도체소자에서 적합한 절연막 임을 확인할 수 있었다. SiOC films were prepared as insulators for displays by sputtering at low temperatures, and the relationship with the electrical properties waaas examined. The electrical properties of SiOC films were affected by the annealing process, and SiOC films annealed at 100 oC showed a significant increase in thickness and a decrease in the reflective index. XRD revealed an increase in the degree of the amorphous structure. Moreover, the capacitance and leakage current of the SiOC films annealed at 100 oC decreased. These characteristics of SiOC films highlight their potential as ideal insulators. Amorphous SiOC films by the reduction of polarization are dependent on the elongation effect of the bonding lengths in the structure and the thickness. The properties of these SiOC films are suitable for low temperature displays.

Study on the Dielectric Constant and on the Degree of Amorphous Structure Induced in Fluorinated Amorphous Carbon Films by Using X-ray Diffraction

오데레사,이광만,최치규 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.4

This work examined the bonding structure of organic materials with low dielectric constants. Fluorinated amorphous carbon films have received much attention because of their similarities to materials with low dielectric constants and because of their hardness, which is similar to that of sp3 carbon structures. The degree of the amorphous structure can be calculated from the Fourier transform of the reduced intensity function by using the corresponding X-ray diffraction patterns. The degree of the amorphous structure is related to the electron density, with the electron density of the fluorinated amorphous carbon films being defined as the result of a nucleophilic reaction based on the C=C bond, for various flow rate ratios. The reaction between the electron-deficient substituent group and the highly electronegative atom leads to the sp3 carbon structure generated by the weak boundary condition due to the high electronegativity of fluorine atoms.

Diels-Alder Reaction by Dienophile with Substitute Group and Bonding Structure of Organic Materials

Oh, Teresa,Kim, Kyung-Sik 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.2

Fluorinated amorphous carbon films have received considerable attention due to their similar properties to low dielectric materials and their hardness similar to the sp3 carbon structure. The degree of the amorphous structure can be calculated by a Fourier transform of the radial distribution function, using the X-ray diffraction patterns. The tendency of amorphous structures in fluorinated amorphous carbon films is divided into two types: high and low degree amorphous structures. The division is originated by the Diels-Alder reaction of organic materials. Among these reactions, the Diels-Alder reaction between the dienophile with electrondeficient substitution group and the diene makes the sp3 carbon structure, and improves the mechanical properties of the surface by a weak boundary condition due to high electronegativity of fluorine atoms.

구미시에 있는 편마암과 관입암체의 카리장석에 대한 상변화 분석

김중욱 大邱敎育大學校 科學敎育硏究所 2001 과학·수학교육연구 Vol.24 No.-

화강암질의 카리장석을 29도에서 31도까지 XRD 회절도 패턴으로 분석하였다. 화강암질 편마암의 카리장석은 최대미사장석 상이며, 그에 반하여 선산화강섬록암은 최대미사장석, 중간미사장석 및 정장석 상이 함께 존재한다. 그러나 석적화강암에서는 정장석 상만이 산출한다. 화강암질편마암의 (131)과 (13￣1) 봉우리들은 선산화강섬록암에 비하여 낮고 안정한 배경값을 지니며, 간격도 넓고 강도도 높은 편이다. 후기암체의 접촉부와 각 암체 안에서 선산화강섬록암의 미사장석은 정장석이나 중간미사장석으로 전이하고 있으나, 화강암질편마암의 미사장석은 정정석까지 전이가 없고, 최대미사장석의 범위에서 트리클리시시티값만 변하고 있다. 이와 같은 카리장석의 상전이 상태로 보아서 화강암질편마암의 카리장석은 선산화강섬록암의 것보다도 후기관입체에 수반한 열과 교대작용으로부터 안정한 것으로 사료된다. K-feldspar in gneiss and intrusives was analyzed by the XRD diffraction patterns from 29˚to 31˚2θ. Granitic gneiss has the maximum microcline phase, whereas Seonsan granodiorite has both the maximum and intermediate microcline phase as well as orthoclase phase. But only orthoclase phase occurs in the Seokjeok granite. The (131) and (13￣1) peaks of k-feldspar in the granitic gneiss have more stable and lower background value, and their intensities are higher and the spacing between two peacks is wider than those of k-feldspar in the Seonsan granodiorite. Microcline of the Seonsan granodiorite has been transformed to intermediate microcline or orthoclase at the contact of the later intrusive pluton and in the inner zone of the Seonsan mass. Whereas mircocline of the granitic gneiss has not been changed to orthoclase, and only the maximum microcline phase has changed from 0.80 to 0.98 in triclinicity(??). From these phase transition trends of k-feldspar in the gneiss and intrusives, it is suggested that k-feldspar of the granitic gneiss is more stable rather than that of Seonsan granodiorite from heating and chemical replacement followed by the later intrusive pluton.

PtMn계 GMR-SV 다층 박막의 열처리 효과 및 저온에서 등방성 자기 저항 특성 연구

최종구,강병욱,이상석 한국물리학회 2018 New Physics: Sae Mulli Vol.68 No.9

Double-type PtMn based on a giant magnetoresistance-spin valve (GMR-SV) multilayer structure was fabricated, and the effect of post-annealing treatment in a magnetic field was investigated. The thin film samples were subjected to a post-annealing treatment, and the isotropic magnetoresistance (MR) characteristics of the thin film crystal structures were analyzed from the X-ray diffraction (XRD) patterns and the magnetoresistance curves measured at room temperature and at liquid-nitrogen temperature, respectively. After annealing, the (111) peak for the face centered cubic (fcc) structure of PtMn had shifted by about 0.5$^\circ$ to the location of the peak for the face centered tetragonal (fct). The exchange coupling field (H$_{ex}$), the coercivity (H$_c$) and the MR ratio having an isotropic magnetic property from the MR curve were 0 Oe, 285 Oe, and 13.0% and 9.2% at 77 K, respectively. These results suggest that the isotropic GMR-SV device composed of two PtMn layers can be used as a biosensor. 이층(double layer) 복합 구조의 PtMn계 거대 자기 저항-스핀밸브(giant magnetoresistance-spin valve, GMR-SV) 다층 박막을 제작하여 자장 내 열처리 효과를 조사하였다. 박막 시료를 후 열처리하여 X-선 회절기(X-ray diffraction, XRD) 패턴으로 상온과 액체질소 온도 상에서 각각 측정한 자기 저항 곡선들부터 박막 결정 구조의 변화에 따른 등방성 자기 저항 특성을 분석하였다. 두 개의 PtMn층이 분리되어 적층한 이층 구조의 스핀밸브 다층 박막을 열처리 후 PtMn 면심입방구조(face centered cubic, fcc)(111) 피크가 면심정방정구조(face centered tetragonal, fct)(111) 피크로 약 0.5$^\circ$ 정도 천이되었다. 열처리 전과 후 박막 시료에 대해 교환결합세기(H$_{ex}$)와 보자력(H$_c$)은 각각 0 Oe와 285 Oe이며, 겹쳐진 자기 저항(magnetoresistance, MR)비는 13.0%와 9.2%으로 향상된 등방성 자기적 특성을 나타내었다. 이러한 결과는 두 개의 PtMn 층으로 구성된 GMR-SV 소자를 바이오센서로 활용할 수 있음을 제시하였다.

아코야 진주의 화학조성과 내부구조가 진주광택에 미치는 영향에 관한 연구

성민준,박지민,장윤득 한국패류학회 2012 The Korean Journal of Malacology Vol.28 No.2

The patterns in X-ray diffraction (XRD) spectroscopy provide useful clue at 29.4˚ to discriminate two types of Akoya cultured pearl which occurs difference of surface luster. Using the optical microscope, we could be confirmed that the nareous layer of each sample consist of different crystal form. In Fourier Transform Infrared (FT-IR) Spectroscopy analysis, the nareous layer of Akoya cultured pearls with poor luster shows some peaks at 712, 699, 1435, 1444 cm-1 region and these peaks depend on the Calcite. But the nareous layer of pearls with excellent luster could not observed those peaks related with Calcite, we could observed Aragonite band at 699, 1085 cm-1 region. Though this result, we know that the nareous layer of Akoya cultured pearls with excellent luster is mainly composed by Aragonite. Raman bands are also clearly demonstrated to occur difference of band intensity by difference of Aragonite content. In the Scanning Electron Microscope (SEM) analysis, we found that the Akoya cultured pearl luster and surface condition is associated with internal structure. 우리는 같은 지역에서 생성된 진주의 표면품질 차이점의 원인을 다양한 분석을 통해 분석하고자 하였다. 본 연구들을 토대로 진주의 표면품질은 진주를 구성하고 있는 아라고나이트와 방해석의 함유량의 차이에 의해 발생되는 것으로 추정되었다. 또한, 내부 구조분석을 통해 표면품질이 서로 다른 진주의발생원인은 내부구조와 일정한 연관성이 있는 것으로 판단되었으며 진주의 생성환경 또한 영향을 줄 것이라 사료되었다. 하지만 앞서 실시한 대부분의 실험들이 파괴분석이며 이러한분석들은 진주와 같은 가치 있는 샘플에 부적합하므로 앞으로새로운 방법의 실험들이 진행되어야 할 것이다.

Improvement in the Hydrogen-Storage Properties of Mg2Ni by Adding LiBH4

Young Jun Kwak,Myoung Youp Song,Ki-Tae Lee 대한금속·재료학회 2024 대한금속·재료학회지 Vol.62 No.4

To improve the hydrogen-storage properties of Mg2Ni, LiBH4 was added by milling in hydrogenatmosphere (reactive mechanical milling, RMM). Mg2Ni-10LiBH4 was prepared with a composition of 90 wt%Mg2Ni + 10 wt% LiBH4. The quantity of released hydrogen (Hr) versus temperature T curve for Mg2Ni-10LiBH4 was obtained by heating at a rate of 4~5 K in 1.0 bar hydrogen. The hydrogen-storage propertiesof the sample were investigated. The phases formed were examined from the x-ray diffraction (XRD) patternsof the samples after RMM, and after hydrogen-absorption and release cycling. The XRD pattern of Mg2Ni-10LiBH4 showed that this sample contained Mg2Ni, Mg2NiH4, o-LiBH4, h-LiBH4, Ni, and MgH2. The dHr/dTversus T curve exhibited three peaks at 325 K, 563 K, and 600 K, respectively. The peak at 325 K is for thehydrogen release from o-LiBH4 and h-LiBH4. The peak at 563 K is for the hydrogen release from Mg2NiH4and the peak at 600 K is for the hydrogen release from Mg2NiH4 and MgH2. The RMM of Mg2Ni with addedLiBH4 creates defects and cracks. RMM facilitates nucleation, increases reactivity, and shortens the diffusiondistances of hydrogen atoms. Expansion and contraction of lattices due to cycling has effects similar to, butweaker than, the effects of RMM.

베타전지용 PN 접합 반도체 표면에 도금된 Ni 후막의 특성

김진주,엄영랑,박근용,손광재 한국방사선산업학회 2014 방사선산업학회지 Vol.8 No.3

Nickel (Ni) electroplating was implemented by using a metal Ni powder in order toestablish a 63Ni plating condition on the PN junction semiconductor needed for production of betavoltaicbattery. PN junction semiconductors with a Ni seed layer of 500 and 1000 Å were coatedwith Ni at current density from 10 to 50 mA cm-2. The surface roughness and average grain size ofNi deposits were investigated by XRD and SEM techniques. The roughness of Ni deposit wasincreased as the current density was increased, and decreased as the thickness of Ni seed layer wasincreased. The results showed that the optimum surface shape was obtained at a current density of10 mA cm-2 in seed layer with thickness of 500 Å, 20 mA cm-2 of 1000 Å. Also, pure Ni deposit waswell coated on a PN junction semiconductor without any oxide forms. Using the line width of (111)in XRD peak, the average grain size of the Ni thick firm was measured. The results showed thatthe average grain size was increased as the thickness of seed layer was increased.

Sol–gel synthesis and structural and luminescent characteristics of a Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 polycomponent solid solution

Palatnikov Mikhail N.,Shcherbina Olga B.,Masloboeva Sofja M.,Smirnov Maxim V.,Sidorova Olga V.,Kadetova Alexandra V.,Zelenina Elena V.,Efremov Vadim V.,Fedorinova Yulia P. 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.4

In the work, a fine powder of GdNb0.9Ta0.1O4-mixed gadolinium tantalum niobate activated with rare earth (REE) cations (Sm3+, Eu3+, Tb3+ and Er3+) was obtained by sol–gel synthesis. The evolution of the powder from amorphous to crystalline form was also studied in the work. The evolution was studied by synchronous thermal and X-ray analysis. The phase composition and structure of the resulting Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 powders were analyzed in detail. Ceramic samples of the Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 polycomponent solid solution were prepared from the sol–gel synthesized powder using traditional ceramic technology. The phase composition and characteristics of the structure of individual phases of the Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 ceramic solid solution was determined by full-profile analysis of XRD patterns of polycrystals. We established that incorporation of REE (Tb, Er, Eu, Sm) into the gadolinium site in GdNb0.9Ta0.1O4 solid solution leads to various distortions of the corresponding polyhedra. Note that the distortion degree in this case is much greater than the distortion of the initial GdNbO4 structure. The photoluminescent (PL) properties of the Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 solid solution were studied in the visible wavelength range. Analysis of literature and our own data revealed: electronic relaxation pathways in Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 ceramics can be different depending on the energy of the exciting radiation. Excitation by the 376 nm line leads to internal energy conversion over 4fn–4fn levels of REE cations (Sm3+, Eu3+, Tb3+ and Er3+). The energy transfer between the Nb4+–O−–Ta4+–O− groups and REE is maximal in this case, while the radiation of the matrix from Nb4+–O−–Ta4+–O− emission centers is minimal. Upon excitation in the near-UV range (376 nm), Gd3+ cations do not participate in the energy transfer between the matrix and 4fn–4fn levels of REE dopants. The maximum PL of Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 ceramics is observed in the green–red region of the spectrum from 5D0–7F2 and 4G5/2–6H7/2 transitions of Eu3+ and Sm3+. The emission is maximal at ~ 612 nm; it corresponds to the 5D0–7F2 electric dipole transition of the Eu3+ cation. We established that the efficiency of energy transfer between the matrix and doping REE cations for Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 ceramics strongly depends on the energy of the exciting radiation.