• Journal of Electrical Engineering and Technology
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• v.12 no.6
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• pp.2353-2358
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• 2017

A femtosecond laser pre-annealing process based on indium zinc oxide (IZO) thin-film transistors (TFTs) is fabricated. We demonstrate a stable pre-annealing process to analyze surface structure change of thin films, and we maintain electrical stability and improve electrical performance. Furthermore, dynamic electrical characteristics of the IZO TFTs were investigated. Femtosecond laser pre-annealing process-based IZO TFTs exhibit a field-effect mobility of $3.75cm^2/Vs$, an $I_{on}/I_{off}$ ratio of $1.77{\times}10^5$, a threshold voltage of 1.13 V, and a subthreshold swing of 1.21 V/dec. And the IZO-based inverter shows a fast switching behavior response. From this study, IZO TFTs from using the femtosecond laser annealing technique were found to strongly affect the electrical performance and charge transport dynamics in electronic devices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.46-46
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• 2006

$SrTiO_3$ was annealed at two different annealing times (1 h and 16 h) to investigate the annealing effect on the grain size and orientation distribution. Electron backscattered diffraction (EBSD) was used to analyze the grain size and grain orientation distributions of the $SrTiO_3$. It is possible to understand the annealing effect on the microstructure evolution, by comparing the grain size and orientation distribution of the $SrTiO_3$ as a function of annealing time.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.183-183
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• 1999

The phases and interface formation of MgF2 on Si(111) were studied by using LEED, AES, and TPD. When thick MgF2 film was deposited on the Si(111) surface at RT뭉 annealed at higher temperatures, a sequence of LEED patterns (no LEED pattern $\longrightarrow$1$\times$1$\longrightarrow$3$\times$1$\longrightarrow$7$\times$7) was observed. On the 1$\times$1 model in which Mg adsorbs on T4 site and F on H3 site could explain the simultaneous desorption of SiF2 and Mg. When thin MgF2 film was deposited, and initial $\alpha$-$\times$1 phase transforms to 3$\times$3 and $\beta$-1$\times$1 by thermal annealing with a slow evaporation of F and diffusion of Mg into the surface. the 3$\times$3 surface changes to ${\gamma}$-1$\times$1 by the selective desorptioon of F under e-beam irradiation and subsesquently to a Mg-induced {{{{ SQRT { 3} }}}} structure by annealing at $600^{\circ}C$.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.4
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• pp.77-82
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• 2010

Effects of evaporation processes and a reduction annealing on thermoelectric properties of the Sb-Te thin films prepared by thermal evaporation have been investigated. The thin film evaporated by using the powders formed by crushing a $Sb_2Te_3$ ingot as an evaporation source exhibited a power factor of $2.71{\times}10^{-4}W/m-K^2$. The thin film processed by evaporation of the mixed powders of Sb and Te as an evaporation source showed a power factor of $0.12{\times}10^{-4}W/m-K^2$. The thin film fabricated by coevaporation of Sb and Te dual evaporation sources possessed a power factor of $0.73{\times}10^{-4}W/m-K^2$. With a reduction annealing at $300^{\circ}C$ for 2 hrs, the power factors of the films evaporated by using the $Sb_2Te_3$ ingot-crushed powders and coevaporated with Sb and Te dual evaporation sources were remarkably improved to $24.1{\times}10^{-4}W/m-K^2$ and $40.2{\times}10^{-4}W/m-K^2$, respectively.

• Composites Research
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• v.18 no.2
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• pp.38-45
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• 2005

Phase transformation behaviors and crystal structures of Nitinol shape memory alloy $(54.5Ni-45.5Tiwt\%)$ are investigated by varying annealing heat treatment conditions through DSC (Differential Scanning Calorimetry) and XRD (X-Ray Diffraction). Annealing heat treatment conditions were considered as heat treated times of 5min, 15min. 30m1n, and 45min, as well as heat treated temperatures of $400^{\circ}C,\;500^{\circ}C,\;525^{\circ}C,\;550^{\circ}C,\;575^{\circ}C,\;600^{\circ}C,\;700^{\circ}C,\;800^{\circ}C,\;and\;900^{\circ}C$ According to the results, annealing heat treatment conditions such as heat treated times and heat treated temperatures were found to affect significantly on phase transformation behaviors and crystal structures of Nitinol shape memory alloy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.276-276
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• 2008

Transparent and conducting indium tin oxide (ITO) and ITO/Nickel/ITO(INI) multilayered films were prepared on glass substrates by a magnetron sputtering without intentional substrate heating. The RF(13.56MHz) and DC power were applied to ITO and Nickel target, respectively. The thickness of ITO, Ni and ITO films were kept constantly at 50, 5 and 45 nm. In order to consider the effect of post deposition vacuum annealing in vacuum on the physical and optoeletrical properties of INI films, optical transmittance, electrical resistivity, crystallinity of the films were analyzed. From the observed result, it may conclude that the optoelectrical properties of the INI films were dependent on the post deposition annealing. For the INI films annealed at $300^{\circ}C$, the films have a polycrystalline structure with (110), (200), (210), (211) and (300). The resistivity of the films were $4.0\times10^{-4}{\Omega}cm$ at room temperature. As the annealing($300^{\circ}C$), resistivity decreased to $2.8\times10^{-4}{\Omega}cm$. And also the optical transmittance decreased from 79 to 70 % at 550nm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.260-261
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• 2008

In this study, we investigated the properties of Indium Zinc Oxide (IZO) films prepared in facing targets sputtering (FTS) system at room temperature as function of oxygen contents. As as-deposited films were rapidly thermal annealing on air atmosphere of $400^{\circ}C$ for 30s. As a result, the transmittance of IZO films increased with increasing oxygen flow in the visible range. After rapidly thermal annealing to films, the optical properties of films improved than films deposited at R.T, but the electrical properties decreased. Before RTA treatment, the lowest resistivity IZO is $5.4\times10^{-4}[\Omega{\cdot}cm]$ at oxygen gas flow. But, after RTA treatment, IZO films have the value of lowest resistivity at the lower oxygen gas ratio in compare with before RTA treatment. The resistivity of IZO films is $7.29\times10^{-4}[\Omega{\cdot}cm]$ at pure argon atmosphere.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.3
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• pp.207-212
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• 2007

The concentration profiles of deep energy levels($E_c$ -0.23e V, $E_v$+0.36e V and $E_c$ -0.23e V) in platinum-diffused silicon have generally a sharp gradient in the vicinity of the surface of the silicon wafer. In this work two efficient methods are proposed to obtain the uniform concentration profiles throughout the silicon wafer. One is that the platinum diffusion is carried out at $1000^{\circ}C$ for 1h in oxygen atmosphere. In this case the values of obtained uniform concentration, $1{\times}10^{15}cm^{-3}$ for the $E_c$ -0.23e V level, and 1{\times}10^{14}cm^{-3}$ for the $E_c$ -0.52e V level, are very restricted, respectively. The other is two-step annealing process. The platinum diffusion is carried out at $850{\sim}1100^{\circ}C$ in a nitrogen ambient for 1h and then the annealing is performed at $1000^{\circ}C$ in oxygen ambient after removing platinum-source from the platinum diffused samples. The advantage of this method is that the uniform concentration of these levels required power devices can be controlled by setting the desired temperatures when the platinum diffusion is carried out in nitrogen ambient.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.8
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• pp.481-485
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• 2015

We investigated the effects of annealing on the electrical and thermal properties of ZTO/4H-SiC heterojunction diodes. A ZTO thin film layer was grown on p-type 4H-SiC substrate by using solution process. The ZTO/SiC heterojunction structures annealed at $500^{\circ}C$ show that $I_{on}/I_{off}$ increases from ${\sim}5.13{\times}10^7$ to ${\sim}1.11{\times}10^9$ owing to the increased electron concentration of ZTO layer as confirmed by capacitance-voltage characteristics. In addition, the electrical characterization of ZTO/SiC heterojunction has been carried out in the temperature range of 300~500 K. When the measurement temperature increased from 300 K to 500 K, the reverse current variation of annealed device is higher than as-grown device, which is related to barrier height in the ZTO/SiC interface. It is shown that annealing process is possible to control the electrical characteristics of ZTO/SiC heterojunction diode.

• Journal of the Korean Ceramic Society
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• v.43 no.9 s.292
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• pp.532-536
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• 2006

The annealing temperature effect of transparent conducting oxide film grown on glass substrate for solar cell application was studied in this paper. Using pulsed DC magnetron sputtering with 1 at% Al-doped ZnO target, TCO films were deposited on coming 7059 glass at room temperature. Al:ZnO thin films were annealed at 200, 400, Al $600^{\circ}C$ for 10 min and annealing resulted in lower biaxial compressive stress of about 1GPa and increased average crystallite size in all films. The as-grown film shows the resistivity of $1{\times}10^{-2}{\Omega}{\cdot}cm$ and transmittance under 80%, whereas the electrical and optical properties of film annealed at $400^{\circ}C$ are enhanced up to $5{\times}10^{-4}{\Omega}{\cdot}cm$ and 85%, respectively.