• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.307-307
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• 2012

In this study, we investigated that the resistance switching characteristics of Al-doped MgOx films with increasing Al doping concentration and increasing film thickness. The Al-doped MgOx based ReRAM devices with a TiN/Al-doped MgOx/Pt/Ti/SiO2 were fabricated on Si substrates. The 5 nm, 10 nm, and 15 nm thick Al-doped MgOx films were deposited by reactive dc magnetron co-sputtering at $300^{\circ}C$ and oxygen partial ratio of 60% (Ar: 16 sccm, O2: 24 sccm). Micro-structure of Al-doped MgOx films and atomic concentration were investigated by XRD and XPS, respectively. The Al-doped MgOx films showed set/reset resistance switching behavior at various Al doping concentrations. The process voltage of forming/set is decreased and whereas the initial current level is increased with decreasing thickness of Al-doped MgOx films. Besides, the initial current of Al-doped MgOx films is increased with increasing Al doping concentration in MgOx films. The change of resistance switching behavior depending on doping concentration was discussed in terms of concentration of non-lattice oxygen of Al-doped MgOx.

• Journal of the Semiconductor & Display Technology
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• v.4 no.2 s.11
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• pp.1-5
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• 2005

Electon spin resonance measurements have been performed on the Mg-doped wurtzite GaN thin films grown on sapphire substrates by low-pressure metal-organic chemical vapor deposition. The sample set included films as-grown with the regular Mg doped and Mg delta doped samples and the corresponding annealed ones. The resonance signal has been observed from the annealed Mg delta-doped sample with the Lande g value of 2.029. This indicates that the singlet resonance signal originates from the neutral Mg acceptor located at 0.24 eV above the valence band edge and 0.13 eV above the Fermi level because of the nuclear hyperfine spin 1=0 of Mg and the larger value than the free electron g=2.0023.

• Transactions on Electrical and Electronic Materials
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• v.11 no.1
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• pp.37-41
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• 2010

The authors investigated the photoluminescence (PL) and the electron paramagnetic resonance (EPR) from an magnesium (Mg)-doped GaN thin film with a delta-doped layer. The regularly doped sample shows a PL peak at 2.776 eV for the as-grown sample, and the peak shifts to 2.904 eV and increases in intensity for the annealed sample. The delta-doped sample also shows the same PL peak as does the regularly doped sample. However, only the annealed delta-doped layer shows a sharp EPR with a small isotropic Lande g-factor, $g_{II}$, of 2.029. This resonance is attributed to the delta-doped layer, which forms a hole-bound Mg-N atomic structure instead of the $Mg_{Ga}-V_N$ defect complex, indicating that the delta-doped sample was not optically activated to form PL centers but was instead electrically activated to form a hole-bound state.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.375-378
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• 2006

Characteristics of doped MgO layer deposited under hydrogen atmosphere were investigated. Hydrogen gas was introduced during e-beam evaporation of doped MgO and its effects on microstructure, cathodoluminescence, discharge voltages and effective yield of secondary electron emission were examined. The results indicated that the hydrogen influences and doped impurities the concentration and energy levels of defects in MgO layer and that affects the luminance efficiency and discharge delays of the panels significantly.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.6
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• pp.275-281
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• 2017

AlN is a promising material for wide band gap and high-frequency electronics device due to its wide bandgap and high thermal conductivity. AlN has advantages as materials for power semiconductors with a larger breakdown field, and a smaller specific on-resistance at high voltage. The growth of a p-type AlN epilayer with high conductivity is important for a manufacturing an AlN-based applications. In this paper, Mg doped AlN epilayers were grown by a mixed-source HVPE. Al and Mg mixture were used as source materials for the growth of Mg-doped AlN epilayers. Mg concentration in the AlN was controlled by modulating the quantity of Mg source in the mixed-source. Surface morphology and crystalline structure of AlN epilayers with different Mg concentrations were characterized by FE-SEM and HR-XRD. XPS spectra of the Mg-doped AlN epilayers demonstrated that Mg was doped successfully into the AlN epilayer by the mixed-source HVPE.

• Progress in Superconductivity
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• v.10 no.1
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• pp.17-22
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• 2008

We have examined the effect of ball-milling on the superconducting properties of $MgB_2$ doped with C. The ball-milling of pre-reacted $MgB_2$ powder was carried out in dry or wet state using C or diethylenetriamine ($C_{4}H_{13}N_3$) as additives. The diethylenetriamine, whose chemical formula contains no oxygen, was chosen to avoid an excess oxidation during doping. The superconducting transition temperature (Tc) of the ball-milled or doped $MgB_2$ powders was only slightly smaller than that of undoped $MgB_2$. The critical current density (Jc) of the highly ball-milled $MgB_2$ was higher than that of C-doped $MgB_2$. The addition of diethylenetriamine was detrimental to Jc, although Tc was almost unchanged.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.1-4
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• 1991

The applicability of $LiNbO_{3}$ as a substrate for fabrication of Ti-indiffused waveguide electro-optic devices is limited. Ti diffuses comparatively in congruently melting $LiNbO_{3}$; the Curie temperature of this material is too low to permit diffusion temperatures much above $1100^{\circ}C$ without the necessity of re-poling the crystal. Both of hese difficulties could be eliminated by incorporating certain dopants in $LiNbO_{3}$. Crystals of $LiNbO_{3}$ doped with Ti and Mg were grown and evaluated. The electroptic coefficients and birefringence of $LiNbO_{3}$ doped crystals were measured at ${\lambda}=.6328$ and $1.32\;$\mu{m}$. Curie temperatures were measured. The Curie temperature of both undoped and Ti-doped $LiNbO_{3}$ was $1130^{\circ}C$; that for Mg-doped $LiNbO_{3}$ was $30^{\circ}$ higher. From these data, a composition for the crystals was estimated. Thermogravimetric data confirmed this estimate and showed that the composition of Mg : $LiNbO_{3}$ was $49.3{\pm}0.2mole%\;Li_{2}O$ ; the composition of the undoped and Ti : $LiNbO_{3}$ samples was $48.6{\pm}0.2mole%$. Diffusion of Ti into both Mg-doped and Ti-doped $LiNbO_{3}$ crystals was studied as a function of $Li/NbO_{3}$ ratio and temperature.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.759-762
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• 2003

The epitaxially grown Mg-doped GaN thin film was prepared by MOCVD (Metal Organic Chemical Vapor Deposition) for a SAW(Surface Acoustic Wave) filter. Mg-doped GaN thin film had enough properties for a SAW filter which include crystallinity and morphology. The surface morphology and crystalline of the Mg-doped GaN thin films were characterized using AFM and an X-ray rocking curve. The SAW filter, which was fabricated by lift-off process and frequency response, was measured by HP 8753C network analyzer. Center frequency was 96.687 MHz and SAW velocity was 5801 m/s when wavelength(λ) was 60${\mu}{\textrm}{m}$. Insertion loss was over -10 dB, Q was factor over 200, and side lobe attenuation was over 22 dB which was suitable for use as a SAW filter. Electro-mechanical coupling coefficient (k$^2$) was calculated from the measured data. k$^2$ was from 1 % to 1.44 %. The fabricated SAW filter using Mg-doped GaN/sapphire structure has good qualities as a filter and will be used as a SAW filter for operating RF frequency.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1993-1997
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• 2012

Mg-doped ZnO one-dimensional (1D) nanostrutures were synthesized by using a thermal evaporation technique. The morphology, crystal structure, and sensing properties of the Mg-doped ZnO nanostructures functionalized with Pt to CO gas at $100^{\circ}C$ were examined. The diameters of the 1D nanostructures ranged from 80 to 120 nm and that the lengths were up to a few tens of micrometers. The gas sensors fabricated from multiple networked Mg-doped ZnO nanowires functionalized with Pt showed enhanced electrical response to CO gas. The responses of the nanowires were improved by approximately 70, 69, 111, and 81 times at CO concentrations of 10, 25, 50, and 100 ppm, respectively. Both the response and recovery times of the nanowire sensor for CO gas sensing were not nearly changed by Pt functionalization. It also appeared that the Mg doping concentration did not influence the sensing properties of ZnO nanowires as strongly as Pt-functionalization. In addition, the mechanism for the enhancement in the CO gas sensing properties of Mg-doped ZnO nanowires by Pt functionalization is discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.43-46
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• 2002

Ferroelectric Mg-doped SBT and Ti-doped SBT were successfully deposited on Pt/Ti/$SiO_2/Si$ substrate by using a sol-gel solution coating method. The solutions were prepared through out adding the metal alkoxide solutions to SBT solution. The typical hysteresis loop of the films was obtained at 5V. The measured $2P_r$ value were $16.50{\mu}C/cm^2$ for SBT, $18.98{\mu}C/cm^2$ and for Mg-doped SBT, and $17.10{\mu}C/cm^2$ for Ti-doped SBT at an applied voltage of 5V, respectively. And it is found that the leakage current densities are less than $10^{-7}A/cm^2$ when applied voltage is less than 10.8MV/cm, which indicates the excellent insulating characteristics.