• The Korean Journal of Ceramics
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• v.6 no.2
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• pp.116-119
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• 2000

The a-axis and c-axis prefer oriented SBT thin films could be deposited on Pt(111)/Ti/$SiO_2$$650^{\circ}C$). The c-axis preferred orientation of SBT film can be obtained by Sr deficiency and high compressive stress. However, the a-axis-oriented grains can be formed under stoichiometric Sr content and nearly stress-free state.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.685-687
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• 1999

We prepared ZnO thin film with Facing Targets Sputtering system that can deposit thin film in plasma-free situation and change the deposition condition in wide range. And prepared thin films c-axis orientation and grain size were analyzed by XRD(x-ray dffractometer). In the results, we suggest that FTS system is very suitable to preparing high quality ZnO thin film with good c-axis orientation.

• Journal of the Korean institute of surface engineering
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• v.33 no.1
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• pp.34-37
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• 2000

We prepared ZnO thin film with Facing Targets Sputtering system that can deposit thin film in plasma-free situation and change the deposition condition in wide range. And prepared thin film's c-axis orientation and grain size were analyzed by XRD (x-ray diffractometer). In the results, we suggest that FTS system is very suitable to preparing high quality ZnO thin film with good c-axis orientation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.415-418
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• 1999

In this paper we studied that the effect of substrate temperature on crystallography and electrical properties of ZnO thin films. Facing Targets Sputtering system can deposit thin films in plasma-free situation and change the deposition condition in wide range. And prepared thin film\`s c-axis orientation and grain size were analyzed by XRD(x-ray diffractometer). In the results, we suggest that FTS system is very suitable to preparing high quality ZnO thin film with good c-axis orientation.

• The Korean Journal of Ceramics
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• v.3 no.2
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• pp.110-115
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• 1997

Li-doped ZnO films were prepared on Corning 1737 glass substrate by an rf magnetron sputtering technique using ZnO targets with various $Li_2CO_3$ contents ranging from 0 to 10 mol%. The effects of Li doping on the crystallinity and electrical properties of ZnO films were studied for their SAW filter applications. The film resistivity largely increased without suppressing the c-axis orientation and crystallinity with a small addition of Li. Heat treatment of the film at 40$0^{\circ}C$ induced that the film resistivity, c-axis orientation and crystallinity slightly increased. However, heat treatment of the film at 50$0^{\circ}C$ resulted in much lower resistivity than that of as-deposited film due to the increase of electron concentration caused by the evaporationof Li atoms from the ZnO film. Large addition of Li into the ZnO film rather diminished the film resistivity and suppressed the c-axis growth. It was concluded that a small doping of Li into the ZnO film and heat treatment at 40$0^{\circ}C$ caused the film resistivity to be high enough for SAW filter applications without suppression of the c-axis orientation and crystallinity.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1209-1211
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• 1993

In this paper, the relationship between electrical breakdown properties and the molecular orientation owing to elongation was investigation from electrical conductivity, electrical breakdown strength and X-ray diffraction wag investigated. The changes of the stretching direction, from an a-axis orientation(at high elongation) to a c-axis orientation(at high elongation), as the elongation increases, were determined from X-ray diffraction patterns. These results suggest that the tendency for a decrease in the trap density at a higher elongation is consistent with a continuous change of the reorientation from the a-axis to the c-axis as the elongation increases.

• Korean Journal of Materials Research
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• v.25 no.3
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• pp.138-143
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• 2015

Aluminum nitride, a compound semiconductor, has a Wurtzite structure; good material properties such as high thermal conductivity, great electric conductivity, high dielectric breakdown strength, a wide energy band gap (6.2eV), a fast elastic wave speed; and excellent in thermal and chemical stability. Furthermore, the thermal expansion coefficient of the aluminum nitride is similar to those of Si and GaAs. Due to these characteristics, aluminum nitride can be applied to electric packaging components, dielectric materials, SAW (surface acoustic wave) devices, and photoelectric devices. In this study, we surveyed the crystallization and preferred orientation of AlN thin films with an X-ray diffractometer. To fabricate the AlN thin film, we used the magnetron sputtering method with $N_2$, NH3 and Ar. According to an increase in the partial pressures of $N_2$ and $NH_3$, Al was nitrified and deposited onto a substrate in a molecular form. When AlN was fabricated with $N_2$, it showed a c-axis orientation and tended toward a high orientation with an increase in the temperature. On the other hand, when AlN was fabricated with $NH_3$, it showed a-axis orientation. This result is coincident with the proposed mechanism. We fabricated AlN thin films with an a-axis orientation by controlling the sputtering electric power, $NH_3$ pressure, deposition speed, and substrate temperature. According to the proposed mechanism, we also fabricated AlN thin films which demonstrated high a-axis and c-axis orientations.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1475-1477
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• 2001

In odor to set high saturation magnetization and coercivity, it had need to orient axis of easy magnetization of CoCr-based thin film perpendicular direction(c-axis) to the substrate plane. It was known that crystalline orientation of CoCr-based thin film was improved by introducing underlayer like Ti, Ge. We prepared singlelayer and double layer with Si underlayer by Facing Targets Sputtering System. As a result, intensity and c-axis dispersion angle ${\Delta}{\theta}_{50}$ of singlelayer were improved with increasing film thickness. Also, it was found that CoCr/Si and CoCrTa/Si double layer showed good c-axis dispersion angle due to introducing Si.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.05a
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• pp.55-58
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• 1993

In this paper, the relationship between trap properties and the molecular orientation owing to elongation was investigation from TSC, electrical conductivity and X-ray diffraction was investgated. The changes of the stretching direction, from an a-axis orientation(at low elongation) to a c-axis orientation(at high elongation), as the elongation increases. were determined from X-my diffraction patterns. These results suggest that the tendency for a decrease in the trap density at a higher elongation is consistent with a continuous change of the reorientation from the a-axis to the c-axis as the elongation increases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.9-13
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• 1995

In this paper, Zinc Oxide films, with a high degree of c-axis orientation, have been grown on glass substrates by a rf magnetron sputtering. The maximum crystal orientation was found to occur with substrate temperature 150$^{\circ}C$, input power 190W, oxygen rate 50%, target-substrate distance 55mm. It is proposed to achieve high-resistivity ZnO films by increasing the annealing temperature. The piezoelectric layers, preferred oriented with (002) perpendicular to the layer with 4.9$^{\circ}$, could be obtained by the annealing temperature 300$^{\circ}C$ in oxygen atmosphere. It is indicated that the relative permittivity is range from 8.9 to 9.8 in the frequency ranging from 10KHz to 5MHz.