• Title/Summary/Keyword: the preferred orientation

Search Result 654, Processing Time 0.027 seconds

A Study on the Preferred Orientation Characteristics of AlN Thin Films by Reactive Evaporation Method using NH3 (NH3를 이용한 반응성 증착법에 의한 AlN 박막의 우선배향특성에 관한 연구)

  • Oh, Chang-Sup;Han, Chang-Suk
    • Korean Journal of Metals and Materials
    • /
    • v.50 no.1
    • /
    • pp.78-85
    • /
    • 2012
  • Aluminum nitride(AlN) is a compound (III-V group) of hexagonal system with a crystal structure. Its Wurzite phase is a very wide band gap semiconductor material. It has not only a high thermal conductivity, a high electrical resistance, a high electrical insulating constant, a high breakdown voltage and an excellent mechanical strength but also stable thermal and chemical characteristics. This study is on the preferred orientation characteristics of AlN thin films by reactive evaporation using $NH_3$. We have manufactured an AlN thin film and then have checked the crystal structure and the preferred orientation by using an X-ray diffractometer and have also observed the microstructure with TEM and AlN chemical structure with FT-IR. We can manufacture an excellent AlN thin film by reactive evaporation using $NH_3$ under 873 K of substrate temperature. The AlN thin film growth is dependent on Al supplying and $NH_3$ has been found to be effective as a source of $N_2$. However, the nuclear structure of AlN did not occur randomly around the substrate a particle of the a-axis orientation in fast growth speed becomes an earlier crystal structure and is shown to have an a-axis preferred orientation. Therefore, reactive evaporation using $NH_3$ is not affected by provided $H_2$ amount and this can be an easy a-axis orientation method.

The Preferred Orientation of CdSe and CdS Thin Films on the AlOx and SiO2 Templates (AlOx와 SiO2 형판위 CdSe와 CdS 박막의 우선방위(Preferred Orientation) 특성)

  • Lee, Young-Gun;Chang, Ki-Seog
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.15 no.4
    • /
    • pp.502-506
    • /
    • 2012
  • In order to find the structural characteristics of the thin films of group II-VI semiconductor compounds compared with those of powder materials, films were made of 4 powders of ZnS, CdS, CdSe, and CdTe(Aldrich), each with 99.99 % purity. For the ZnS/CdS multi-layers, the ZnS layer was coated over the CdS layer on an $AlO_x$ membrane, which served as a protective layer within a vacuum at the average speed of 1 ${\AA}$/sec. After studying the structures of the group II-VI semiconductor thin films by using X-ray spectroscopy, we found that the ZnS, ZnS/CdS, CdS, and CdSe films were hexagonal and exhibited some degree of preferred orientation. Also, the particles of the thin films of II-VI semiconductor compounds proved to be more homogeneous in size compared to those of the powder materials. These results were further verified through scanning electron microscopy(SEM), EDX analysis, and powder and thin film X-ray diffraction.

Sensation Seeking Tendency and Shopping Orientation affect on Preferred Fashion Style of Female College Students (여대생의 감각추구 및 쇼핑성향에 따른 패션스타일 선호도)

  • Park, Hyun-Jeong;Na, Young-Joo
    • Fashion & Textile Research Journal
    • /
    • v.5 no.5
    • /
    • pp.495-502
    • /
    • 2003
  • This study aims to investigate the relationships among sensation seeking tendency and shopping orientation and the preferences of fashion styles of female college students. The sensation seeking was found related with shopping orientation, and style preference. 'Seeking change' tendency and 'seeking unusual sensation' are related to 'hedonic shopping orientation', while 'seeking adventure/satisfying curiosity' is related to 'impulsive shopping orientation'. As 'seeking adventure/satisfying curiosity' increased, the preference of 'vivid character style' increased. The cross-effect of seeking sensation and shopping orientation affected style preference. Allowance and residential location affected the seeking sensation, shopping orientation and preference styles, while monthly spending on clothing and residential type affected shopping orientation only. The students with large allowance showed high 'seeking adventure/satisfying curiosity', high 'brand loyalty and impulsive' shopping orientation, and high preference in 'accessory and conspicuous style'. The students residing in Inchon showed high 'seeking unusual sensation', and 'practical shopping orientation', and low 'accessory and conspicuous style' than Seoul students.

Effects of Physico-chemical Factors of Sol on the Degree of Preferred Orientation in $Pb(Mg, Zn)_{1/3}Nb_{2/3}O_3$ Thin Films (Sol의 물리화학적 변수들이 $Pb(Mg, Zn)_{1/3}Nb_{2/3}O_3$ 박막의 우선 배향성에 미치는 효과)

  • 조문규;장현명;김광수
    • Journal of the Korean Ceramic Society
    • /
    • v.32 no.3
    • /
    • pp.305-312
    • /
    • 1995
  • Thin films of Pb(Mg, Zn)1/3Nb2/3O3 were fabricated by spin coating the Pb-Mg-Zn-Nb-O complex alkoxide sols on(111) Pt-coated MgO (100) planes. It was observed that the content of H2O and the rheological characteristics of sol greatly influenced the orientation of perovskite grains after thin-film formation. A strong preferential orientation of (100)-type planes of the perovskite grains was obtained for the sol aged for 15 days with the molar ratio of H2O to total metal alkoxides=2. As small angle X-ray scattering experiment in the Porod region was performed to correlate the observed preferential orientation with the network structure of precursors at various stage of aging. It was shown that the degree of branching of the Pb-Mg-Zn-Nb-O precursor chain had a direct effect on the preferred oreintation, and weakly branched precursor systems led to highly oriented grains after thin-film formation.

  • PDF

Microstructure of Zinc electrodeposit in Cyanide Solution (시안화아연욕을 사랑한 아연 전착층의 조직특성)

  • Ye G.C;Cho E.H.
    • Journal of the Korean institute of surface engineering
    • /
    • v.17 no.2
    • /
    • pp.41-58
    • /
    • 1984
  • Zinc was electrodeposited from cyanide solutions at temperature from 20$^{\circ}C\;to\;40^{\circ}C$ in the range of current density from 0.5 to 8A/$dm^2$. The preferred orientation changed from (10.3)+(11.0) to (11.0) texture with increasing cathode overpotential in the additive free solution, while the (11.0) preferred orientation developed at lower overpotentials (800-1270 mV) and the (11.0)+(10.0) preferred orientation was formed at higher overpotential (1300-1400mV) in the solution with brightner. Mossy type of morphology developed mostly in the additive free deposits and the microstructure of the cross section of the above deposits changed from columar structure to granular structure with increasing overpotential. The surface appearance of the deposits with additive having (11.0) texture was the smooth deposit of very small crystallite, while that of the deposits having (11.0)+(10.0) texture was fine crystalline deposit. The microstructure of the cross section of them was the fine field oriented type of structure.

  • PDF

The Relationships between the Preservice Elementary Teachers' Goal Orientations for Science Teaching and Their Images of Science Class (초등학교 예비교사의 교수목표 지향성과 과학 수업 이미지 사이의 관계)

  • Jeon, Kyungmoon
    • Journal of Korean Elementary Science Education
    • /
    • v.37 no.4
    • /
    • pp.430-439
    • /
    • 2018
  • The preservice elementary teachers' goal orientations for science teaching (mastery/ability-approach/ ability-avoidance/work-avoidance goal) were measured. We also examined how the goal orientations were related to their images of science class (preferred/avoided). The results showed that the student teachers (75 males and 82 females) tended to have the mastery or ability-approach goals rather than the ability-avoidance or work-avoidance goals for science teaching. For avoided class, they tended to show teacher-centered components (eg., teacher: lecturing, students: watching and listening, environment: chalkboard), while rarely to show such teacher-centered components for preferred class. Regarding the relationships between the goal orientations and the images of science class, the significantly positive relationship was found between the ability-approach goal orientation and teacher-centered image of avoided class. However, the teacher-centered image for preferred class was positively related to the ability-avoidance goal orientation. The educational implications and future directions were discussed.

The effect of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy electrodeposits (Ni-Fe합금도금층의 조선 및 우선배향에 미치는 전해조건의 영향)

  • 예길촌;김용웅;김용희;김용주
    • Journal of the Korean institute of surface engineering
    • /
    • v.27 no.6
    • /
    • pp.319-326
    • /
    • 1994
  • The effects of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy were studied using the sulfate-chloride baths paddle agitated. Cathode current efficiency is higher in the deposits from bath 2 than that of deposits from bath 1. The Fe content of alloy deposits from bath 2 is nearly constant(19∼21wt.%) in the wide range of current density, while it decreases noticeably with current density in the deposits from bath 1. The variation of Fe content at the edge of specimen is lower in deposits from bath 2 than those from bath 1. The alloy deposits show (111) & (200) preferred orientation for the deposits from bath 1 and bath 2 respectively.

  • PDF

The Microstructure and the Prerred Orientation of Pb-Sn-Alloy Electrodeposits in Pulse Plating (파형점류전해에 의한 Pb-Sn 합금의 현미경조직 및 우선배향)

  • 예길촌;김용응
    • Journal of the Korean institute of surface engineering
    • /
    • v.22 no.4
    • /
    • pp.207-214
    • /
    • 1989
  • The surface morphology and the proferred orientation of the Pb-Sn alloy electrodeposite were investated by the change of electrolysis conditions in pulse current electroplating. The preferred orientation of Pb-phase in alloy deposits was changed in the sequence of (110)longrightarrow(100)or(100)+(111)longrightarrow(111) with increasing peak current density, while that of $\beta$-Sn phase changed from (321)+(301)to(301)+(111) mixed orientation. The surface morphology was closely related to the preferred orientation of alloy electrodeposits. The alloy deposits, which had (100)or(111) for pb-phase and (321)or(100)(301)for $\beta$-Sn sespectively, showed the surface structure of granular crystallites. The alloy deposits whih mixed orientations for both phases had microstructure of closely the closely stacked crysrallites, which was inclined to the surface.

  • PDF

Preferred Orientation, Microstructure, Surface Morphology and Mechanical Properties of Electrodeposited Copper Foils (電解銅薄의 優先方位, 斷面組織, 表面形態 및 機械的 性質)

  • Kim, Yoon-Keun;Lee, Dong-Nyung
    • Journal of the Korean institute of surface engineering
    • /
    • v.18 no.3
    • /
    • pp.95-104
    • /
    • 1985
  • A study has been made of preferred orientation, crose sectional microstructure, surface morphology and mechanical properties of copper foils fabricated by electrodeposition on 304 stainless steel plate from copper sulfate baths for high speed plating. The preferred orientation of the copper foils changed from the [110] to the [111] to ture with decreasing bath temperature and increasing cathode current density. The foils with the [110] texture had the field oriented texture type structure and the surface of many asperities grooved approximately perpendicular to the subtrate. A specimen with the [111]+[311] texture had the lower strength than one with the [10] texture, if they were obtained under similar electrolysis conditions.

  • PDF

The Effect of Trace Metallic Additives on Microstructure, Surface Appearance and Hardness of Zn Electrodeposits (아연도금층의 조직, 외관, 및 경도에 미치는 미량 금속첨가의 영향)

  • 예길촌;김대영;안덕수
    • Journal of the Korean institute of surface engineering
    • /
    • v.37 no.1
    • /
    • pp.28-39
    • /
    • 2004
  • The effect of trace metallic additives on microstructure, surface appearance and hardness of zinc electrodeposits was investigated by using sulfate bath and flow cell system. The preferred orientation of Zn deposit with Fe additive was (103)(104)+(002) mixed texture and that of Zn deposits with both Fe-Ni and Fe-Co additives was (10 1), while Zn deposits with Fe-Cr additives had (002) preferred orientation. The surface morphology of the zinc deposits was closely related to the preferred orientation of the deposits. The glossiness of Zn deposit with Fe-Ni additives was higher than that of pure Zn deposit, while the glossiness of Zn deposits with both Fe-Co and Fe-Cr additives was lower than that of pure Zn deposit. The hardness of Zn deposits with both Fe-Ni and Fe-Co additives was noticeably higher than that of Zn-Fe deposit, while that of Zn deposit with Fe-Cr additives was similar to that of Zn-Fe deposit.