• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.1
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• pp.23-30
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• 1993

Hydrogenation on the top gate and bottom gate Poly-Si TET's was performed by using Nh$_{3}$ plasma and annealing SiN film deposited by PECVD and then the electric characteristics on Poly-Si TET were investigated. As the time of NA$_{3}$ plasma treatment increaes, on/off current ratio gradually increases and the swing value decreases. The trap densities of graim boundaries in Poly-Si decrease very much during the inital 20min of hydrogenation time, and the decreasing scale becomes smaller after 20 min. The electric characteristics of the top gate TFT are better than those of the bottom gate TFT, it is considered due to the defects at the interface between the Poly-Si and the underlayer, SiO$_{2}$. After NH$_{3}$ plasma was treated for 2 hours for the top gate TFT, as the aging time atroon temperature increases on current was not scacely changed and off current decreases more than 1 order. Gate current density recovers to original value after the aging treatment for 8 days and then the electric characteristics are finally improved. It is suggested that the degraded characteristics of gate oxide are improved, from the variations of C-V characteristics with aging time. For the hydrogenation of isothermal and isochronal annealing SiN film deposited by PECVD, the characteristics of Poly-Si TFT are improved with increasing annealing temperature and are not largely changed with increasing annealing time. This results is good in agreement with the hydrogen reduction in Sin film as variations of annealing temperature and time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.701-706
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• 2006

In addition to its similarity to genuine diamond film, diamond-like carbon (DLC) film has many advantages, including its wide band gap and variable refractive index. In this study, DLC films were prepared by the RF PECVD (Plasma Enhanced Chemical Vapor Deposition) method on silicon substrates using methane $(CH_4)$ and hydrogen $(H_2)$ gas. We examined the effects of the post annealing temperature on the structural variation of the DLC films. The films were annealed at temperatures ranging from 300 to $900^{\circ}C$ in steps of $200^{\circ}C$ using RTA equipment in nitrogen ambient. The thickness of the film and interface between film and substrate were observed by surface profiler, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), respectively. Raman and X-ray photoelectron spectroscopy (XPS) analysis showed that DLC films were graphitized ($I_D/I_G$, G-peak position and $sp^2/sp^3$ increased) ratio at higher annealing temperature. The variation of surface as a function of annealing treatment was verified by a AFM and contact angle method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.321-322
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• 2009

Al doped ZnO films deposited on glass substrate using RF magnetron sputtering in Ar and $Ar+H_2$ gas ambient at $100^{\circ}C$. The films deposited in $Ar+H_2$ were hydrogen-annealed at the temperature of $150\sim300^{\circ}C$ for 1hr. The lowest resistivity of $4.25\times10^{-4}{\Omega}cm$ was obtained for the AZO film deposited in $Ar+H_2$ after hydrogen annealing at $300^{\circ}C$ for 1hr. The average transmittance is above 85% in the range of 400-1000 nm for all films. The absorption efficiency of solar cell was improved by using the optimized AZO films as a top electrode.

• Transactions on Electrical and Electronic Materials
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• v.18 no.6
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• pp.316-319
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• 2017

A new approach to improving the electrical characteristics and optical response of a polysilicon-based metal-semiconductor-metal (MSM) photodetector is proposed. To understand the cause of current restriction in the MSM photodetector, modified trap mechanisms are suggested, which include interfacial electron traps at the metal/polysilicon interface and silicon dangling bonds between silicon crystallite grains. Those traps were passivated using hydrogen ion implantation with subsequent post-annealing. Photodetectors that were ion-implanted under optima conditions exhibited improved photoconductivity and reduced dark current instability, implying that the hydrogen bonds in the polysilicon influence the simultaneous decreases in the density of dangling bonds at grain boundaries and the trapped positive charges at the contact interface.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.165-166
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• 2006

Nb-Ti alloys were hydrogenated to prepare fine and contamination-free powders. Cracks were introduced in the alloys when they were annealed at 1473 K and cooled in a hydrogen atmosphere. The fragments produced by hydrogen-induced cracking are brittle and the friability enhanced with the Ti content of the alloy, which is beneficial for further refinement of particle size. We also demonstrate that Nb-Ti powders with the average particle size less than 1 m can be produced by ball milling at a temperature lower than 203 K. Furthermore, hydrogen-free powders can then be obtained by annealing above the temperature corresponding to hydrogen desorption from Nb solid solution.

• Journal of Electrochemical Science and Technology
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• v.12 no.2
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• pp.212-216
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• 2021

We investigated the feasibility of hydrogen storage with electrochemically formed VO₂ nanotubes. The VO₂ nanotubes were fabricated through the anodization of vanadium metal in fluoride ion-containing organic electrolyte followed by an annealing process in an Ar-saturated atmosphere at 673 K for 3 h at a heating rate of 3 K /min. During anodization, the current density significantly increased up to 7.93 mA/cm² for approximately 500 s owing to heat generation, which led to a fast-electrochemical etching reaction of the outermost part of the nanotubes. By controlling the anodization temperature, highly ordered VO₂ nanotubes were grown on the metal substrate without using any binders or adhesives. Furthermore, we demonstrated the hydrogen sorption properties of the anodic VO₂ nanotubes.

• Journal of IKEEE
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• v.23 no.2
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• pp.704-709
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• 2019

In this paper, the electrical characteristics of tunneling field effect transistor(TFET) was studied for different annealing conditions. The TFET samples annealed using hydrogen forming gas(4 %) and Deuterium($D_2$) forming gas(4 %). All the measurements were conducted in noise shielded environment. The results show that subthreshold slope(SS) decreased by 33 mV/dec after annealing process compared to before annealing. Under various temperature range, the noise is improved by average of 31.2 % for 10 atm Deuterium gas at $V_G=3V$ condition. It is also noticed that, post metal annealing with $D_2$ gas reduces the noise by average of 30.7 % at $I_D=100nA$ condition.

• Electronic Materials Letters
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• v.14 no.6
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• pp.749-754
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• 2018

Previous studies have reported on the mechanical robustness and chemical stability of flexible amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) on plastic substrates both in flat and curved states. In this study, we investigate how the polyimide (PI) substrate affects hydrogen concentration in the a-IGZO layer, which subsequently influences the device performance and stability under bias-temperature-stress. Hydrogen increases the carrier concentration in the active layer, but it also electrically deactivates intrinsic defects depending on its concentration. The influence of hydrogen varies between the TFTs fabricated on a glass substrate to those on a PI substrate. Hydrogen concentration is 5% lower in devices on a PI substrate after annealing, which increases the hysteresis characteristics from 0.22 to 0.55 V and also the threshold voltage shift under positive bias temperature stress by 2 ${\times}$ compared to the devices on a glass substrate. Hence, the analysis and control of hydrogen flux is crucial to maintaining good device performance and stability of a-IGZO TFTs.

• Journal of the Korean Electrochemical Society
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• v.3 no.1
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• pp.19-24
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• 2000

It is increasingly necessary to use poly-Si n's as high resolution and integration of Tn for LCD. Excimer Laser Crystallization (ELC) of a-Si is mainly used as a low temperature process. But the ELC method for the fabrication of poly-Si has the eruption problems associated with hydrogen in the a-Si film. So we need a dehydro-genation process additionally. Hydrogen in a-Si film can degrade the quality of poly-Si film and electrical properties of device due to the hydrogen eruption and voids which occur during the excimer laser annealing. In this study, we propose mesh-type PECVD as the a-Si film deposition method for achieving the low concentration hydrogen. Mesh-type PECVD was found to reduce the hydrogen content substantially. We could obtain a as-deposited a-Si film with hydrogen contents less than $1\%$ at $300^{\circ}C$. We also investigated the behavior by XeCl excimer laser annealing of a-Si fabricated by mesh-type PECVB. As a result, we were able to confirm the broad process window in contrast to the narrow process range typically obtained in ELC. Hydrogen eruption was not observed in poly-Si films after ELC These results suggests that mesh-type PECVD is a viable method to achieve the low hydrogen content a-Si and improve the process windows for ELC.

• The Korean Journal of Ceramics
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• v.4 no.1
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• pp.15-19
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• 1998

Defects formation of Chemical Vapor Deposition (CVD) diamond on $^4He^{2+}$ irradiation and after remote hydrogen plasma treatment(RHPT) were investigated by cathodoluminescence(CL). As calculated in the TRIM simulation, the light elements of $^4He^{2-}$ can be penetrated into the diamond bulk structure at 3~4 $\mu\textrm{m}$ depth. The effects of the implantation region were observed when 5 keV~20 keV electron energy (insight 0.3~4.0$\mu\textrm{m}$) of CL measurement was irradiated to diamond at temperature 80 K. After the RHPT, rehybridization of irradiation damaged diamond was studied. The intensity of 5RL center(intrinsic defect of C) was diminished. The 2.16 eV center (N-V center) occurring usually by annealing could not be seen after RHPT. The diamond was rehybridized by hydrogen radicals without etching and thermal degradation by the RHPT.