• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.8
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• pp.711-715
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• 2003

In this study, we prepared ZnO/glass and ZnO/SiO$_2$/Si thin film by Facing Targets Sputtering (FTS) system for Film Bulk Acoustic Resonator (FBAR). When the ZnO thin film applied to piezoelectric thin film, it requires good c-axis preferred orientation. And c-axis orientation has a remarkable difference with preparation conditions. Therefore, c-axis orientation must be significantly evaluated as a function of deposition conditions. Moreover, in order to prepare ZnO thin film with good crystallographic properties and progressive of efficiency of product process, the ZnO thin film should be prepared as low temperature as possible. In this work, we prepared ZnO thin films on slide glass and SiO$_2$/Si substrate. And the crystallographic characteristics of ZnO thin films on sputtering conditions were investigated by alpha-step and X-ray diffraction.

• Journal of the Semiconductor & Display Technology
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• v.11 no.2
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• pp.13-16
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• 2012

Zinc oxide (ZnO) films were deposited by an RF magnetron sputtering system with the RF power of 200W and 300W and flow rate of oxygen gases of 20 and 30 sccm, in order to research the growth of ZnO on carbon doped silicon oxide (SiOC) thin film. The reflectance of SiOC film on Si film deposited by the sputtering decreased with increasing the oxygen flow rate in the range of long wavelength. In comparison between ZnO/Si and ZnO/SiOC/Si thin film, the reflectance of ZnO/SiOC/Si film was inversed that of ZnO/Si film in the rage of 200~1000 nm. The transmittance of ZnO film increased with increasing the oxygen gas flow rate because of the transition from conduction band to oxygen interstitial band due to the oxygen interstitial (Oi) sites. The low reflectance and the high transmittance of ZnO film was suitable properties to use for the front electrode in the display or solar cell.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.880-883
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• 2003

ZnO thin films for Film Bulk Acoustic Resonator(FBAR) were prepared by FTS (Facing Target Sputtering) system. The FTS methode enable to generate high density plasma, and it has a high deposition rate at 1mTorr pressure. Therefore, the ZnO thin films were deposited on $AZO/SiO_2/Si$ substrates with oxygen gas flow rate, and the other sputtering conditions were fixed such as a sputtering current of 0.8A, a substrate temperature at room temperature. AZO bottom electrode were deposited on $SiO_2/Si$ substrate and by Zn:Al(Al:2wt%) metal target. ZnO thin film thickness and the c-axis preferred orientation of ZnO thin film were evaluated by ${\alpha}-step$ and XRD.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.246-248
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• 1994

The Electrical properties of thin $SiO_2$ film by rapid thermal processing have been investigated and this film has been compared with thermal $SiO_2$ film by furnace. The RTO(rapid thermal oxide) film annealed in Ar ambient represent more superior properties than thermal $SiO_2$ film by furnace at breakdown field and leakage current. The RTO(rapid thermal oxide) film annealed in $NH_3$ ambient represent more inferior properties than thermal $SiO_2$ film by furnace at electrical properties, but the capacitance was improved 15-25% than the conventional oxide film.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.826-832
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• 1998

In this study the thin films with the structure of Si+SiO$_2$+TiN are made by RF supttering method. TiN, which has small diffusion coefficient and low resistivity, is evaporated between SiO$_2$ and Al layers. It investigates the V-R characteristics depending on the thickness of SiO$_2$ which is used as insulation layer and researches its effects on voltage stability of thin film and varistor. These films show very small resistance valus in negative(-) voltage and large and large value in positive voltage band, and with the increase of voltage, resistance value is rapidly reduced and the satisfactory characteristic of varistor is shown at +1[V]. It is found that resistance value of TiN thin film is small and also TiN thin film has more current than the thin film which is not evaporated by TiN thin film. When Al electrode is evaporated of SiO$_2$ thin film, spiking occurs, but the spiking can be prevented with evaporation of TiN between SiO$_2$ and Al layers and this thin films in made easily because of its good attachment. With the increase of voltage, the resistance is changed into non-linear pattern and the bidirectional varistor characteristic is shown and then its theory can be verified by this experiment. Accordingly, when TiN is evaporated of Si Wafer(n-100), it obtains better voltage-resistance than thin film which is not evaporated and also when varistor character is used electrically to automatic control element such as elimination of flame, power distribution arrestor and constant voltage compensation, satisfactory reproducibilities are expected.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.9
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• pp.20-28
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• 1992

Dielectric thin film of N/O ($Si_{3]N_{4}/SiO_{2}$) for high density stacked dynamic-RAM cell was formed by LPCVD and oxidation(dry & pyrogenic oxidation methods) of the top 7nm $Si_{3]N_{4}$ film. The thickness, structure and composition of this film were measured by ellipsometer, high resolution TEM, AES and SIMS. The insulating characteristics(I-V characteristics) were investigated by HP 4145, and the characteristics of TDDB (Time Dependent Dielectric Breakdown) were evaluated by using CCST(Current Constant Stress Time) method. In this experiment, The optimum oxidation condition for preparation of good insulating and TDDB characteristics of N/O film was pyrogenic oxidation at 85$0^{\circ}C$ for 30 minutes. The leakage current was reduced from 400pA to 7.5pA when SiO$_{2}$ film with thickness of 2nm was formed on the top of $Si_{3]N_{4}$ film by the pyrogenic oxidation method.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.373-376
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• 2012

Thin films of Ag-SiO2-TiO2 composite oxides with SiO2/TiO2 of 20/80 molar compositions were prepared by the sol-gel method, using tetraethylorthosilicate (TEOS) and titanium isopropoxide (TIP) as precursors. Ag-SiO2-TiO2 films coated on commercial glass substrates have successfully been synthesized using sol-gel method. The Ag-SiO2-TiO2 film with 0.5% Ag-added concentration and 20 mol% SiO2-mixture gives optimal results on crystalline structure, optical property, surface area, and photochromic property. Absorption near the wavelength of the incident light decreased gradually. The reversibility of the two-photon writing process in Ag-SiO2-TiO2 film is clearly seen.

• Journal of the Korean Vacuum Society
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• v.22 no.3
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• pp.126-130
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• 2013

The sodium (Na) and moisture ($H_2O$) gettering phenomena were measured and analyzed in PSG/$SiO_2$ passivated Al-1%Si thin film interconnections. PSG/$SiO_2$ passivation and Al-1%Si thin films were deposited by using APCVD (atmosphere pressure chemical vapor deposition) and DC magnetron sputter techniques, respectively. SIMS (secondary ion mass spectrometry) depth profiling analysis was used to determine the distribution of sodium and moisture throughout the PSG/$SiO_2$ passivated Al-1%Si thin film interconnections. Both sodium and moisture peaks were observed strongly at the interfaces between layers rather than within the Al-1%Si thin film interconnections. Sodium peaks were observed at the interface between PSG and $SiO_2$ passivations, while moisture peaks were not observed.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.231-233
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• 1993

This paper proposes a new $SiO_2$ film condenser fabrication technique by photo-chemically deposited $SiO_2$ films by Laser CVD. Laser CVD is noticeable that film deposition can be done at low temperature below $300^{\circ}C$ with less damage. After film deposition, the characteristics of Laser CVD $SiO_2$ films and $SiO_2$ film condenser is evaluated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.91-95
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• 2012

ZnO thin films were deposited on p-type 4H-SiC substrate by pulsed laser deposition. ZnO nanowires were formed on p-type 4H-SiC substrate by furnace. Ti/Au electrodes were deposited on ZnO thin film/SiC and ZnO nanowire/SiC structures, respectively. Structural and crystallographical properties of the fabricated ZnO thin film/SiC and ZnO nanowire/SiC structures were investigated by field emission scanning electron microscope and X-ray diffraction. In this work, resistance and sensitivity of ZnO thin film/SiC gas sensor and ZnO nanowire/SiC gas sensor were measured at $300^{\circ}C$ with various CO gas concentrations (0%, 90%, 70%, and 50%). Resistance of gas sensor decreases at CO gas atmosphere. Sensitivity of ZnO nanowire/SiC gas sensor is twice as big as sensitivity of ZnO thin film/SiC gas sensor.