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Research has shown that when a microcontroller (MCU) is powered up, the emitted electromagnetic radiation (EMR) patterns are different depending on the executed instructions. This becomes a security concern for embedded systems or the Internet of Things. Currently, the accuracy of EMR pattern recognition is low. Thus, a better understanding of such issues should be conducted. In this paper, a new platform is proposed to improve EMR measurement and pattern recognition. The improvements include more seamless hardware and software interaction, higher automation control, higher sampling rate, and fewer positional displacement alignments. This new platform improves the performance of previously proposed architecture and methodology and only focuses on the platform part improvements, while the other parts remain the same. The new platform can measure EMR patterns for neural network (NN) analysis. It also improves the measurement flexibility from simple MCUs to field programmable gate array intellectual properties (FPGA-IPs). In this paper, two DUTs (one MCU and one FPGA-MCU-IP) are tested. Under the same data acquisition and data processing procedures with similar NN architectures, the top1 EMR identification accuracy of MCU is improved. The EMR identification of FPGA-IP is the first to be identified to the authors' knowledge. Thus, the proposed method can be applied to different embedded system architectures for system-level security verification. This study can improve the knowledge of the relationships between EMR pattern recognitions and embedded system security issues.
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Domestication is an excellent model to study diversification and this evolutionary process can be different in perennial plants, such as fruit trees, compared to annual crops. Here, we inferred the history of wild apricot species divergence and of apricot domestication history across Eurasia, with a special focus on Central and Eastern Asia, based on microsatellite markers and approximate Bayesian computation. We significantly extended our previous sampling of apricots in Europe and Central Asia towards Eastern Asia, resulting in a total sample of 271 cultivated samples and 306 wild apricots across Eurasia, mainly Prunus armeniaca and Prunus sibirica, with some Prunus mume and Prunus mandshurica. We recovered wild Chinese species as genetically differentiated clusters, with P. sibirica being divided into two clusters, one possibly resulting from hybridization with P. armeniaca. Central Asia also appeared as a diversification centre of wild apricots. We further revealed at least three domestication events, without bottlenecks, that gave rise to European, Southern Central Asian and Chinese cultivated apricots, with ancient gene flow among them. The domestication event in China possibly resulted from ancient hybridization between wild populations from Central and Eastern Asia. We also detected extensive footprints of recent admixture in all groups of cultivated apricots. Our results thus show that apricot is an excellent model for studying speciation and domestication in long-lived perennial fruit trees.
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Domesticación , Frutas/genética , Variación Genética/genética , Prunus armeniaca/genética , China , Europa (Continente) , Evolución Molecular , Frutas/crecimiento & desarrollo , Flujo Génico/genética , Hibridación Genética , Especificidad de la EspecieRESUMEN
Five heterometallic ZnII6-LnIII3 macrocycles based on a salicylamide imine multidentate unsymmetrical ligand H2L [1-(2-hydroxy-3-methoxy-benzamido)-2-(2-hydroxy-3-methoxy-benzylideneamino)-ethane] have been prepared via a coordination-driven self-assembly strategy. Single-crystal X-ray diffraction analysis reveals that the five metallocycles are isomorphic with a formula of [Zn6Ln3L6(OH)2(NO3)4(H2O)]·3NO3· nCH3CN (ZnLn-1, where Ln = Pr, Nd, Eu, Tb, or Yb; for ZnPr-1, n = 4; for ZnNd-1, ZnEu-1, and ZnTb-1, n = 2; for ZnYb-1, n = 3), where six octadentate ligands L2- and two in situ-formed µ2-OH- ions bridged the alternating ZnII-LnIII-ZnII subunits into a macrocycle. Along with the structural novelty, ZnNd-1 shows distinctive enhanced emission in the visible and near-infrared range upon addition of OAc-. On the basis of ultraviolet-visible spectroscopy, 1H nuclear magnetic resonance, single-crystal X-ray diffraction, and high-resolution electrospray ionization mass spectrometry, we deduced that this emission enhancement could be attributed to the synergistic effect of TICT and the absent nonradiative transition of µ2-OH- induced distinctively by OAc- bridging. Our results demonstrate that the NdIII-containing heterometallic macrocycle can act as a host for anion exchanging and provide a nice example of heterometallic macrocycles with interesting properties and potential applications.
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Ingenious approaches to supramolecular assembly for fabricating smart nanodevices is one of the more significant topics in nanomaterials research. Herein, by using surface quaternized cationic carbon dots (CDots) as the assembly and fluorescence platform, anionic sulfonatocalix[4]arene with modifiable lower and upper rims as a connector, as well as in situ coordination of Tb(3+) ions, we propose an elaborate supramolecular assembly strategy for the facile fabrication of a multifunctional nanodevice. The dynamic equilibrium characteristics of the supramolecular interaction can eventually endow this nanodevice with functions of fluorescent ratiometric molecular recognition and as a nano-logic gate with two output channels.
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This study presents an band-alignment tailoring of a vertically aligned InAs/GaAs(Sb) quantum dot (QD) structure and the extension of the carrier lifetime therein by rapid thermal annealing (RTA). Arrhenius analysis indicates a larger activation energy and thermal stability that results from the suppression of In-Ga intermixing and preservation of the QD heterostructure in an annealed vertically aligned InAs/GaAsSb QD structure. Power-dependent and time-resolved photoluminescence were utilized to demonstrate the extended carrier lifetime from 4.7 to 9.4 ns and elucidate the mechanisms of the antimony aggregation resulting in a band-alignment tailoring from straddling to staggered gap after the RTA process. The significant extension in the carrier lifetime of the columnar InAs/GaAsSb dot structure make the great potential in improving QD intermediate-band solar cell application.
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In this study, the optical properties of InAs quantum dots (QDs) with various strain-reducing layers (SRLs) of GaAsSb and InGaAsSb are characterized using photoluminescence (PL) and time-resolved PL (TRPL) measurements. The room-temperature PL results for the InAs/InGaAsSb QDs revealed stronger emission intensities than InAs QDs capped with an GaAs(1-x)Sb(x) (x = 20%)SRL, although both samples were grown under the same Sb flux during the molecular beam epitaxy process. The InAs/InGaAsSb QDs showed a significant elongation of emission wavelengths to 1450 and 1310 nm for the ground and first-excited state at room temperature. The energy band alignment of the InAs QD heterostructures was found tailoring from type II to type I as the GaAsSb SRL was replaced by InGaAsSb layer, which improved the radiative efficiency and was verified by power-dependent PL and TRPL measurements. Post-growth rapid thermal annealing was applied on the InAs/InGaAsSb QDs to further enhance the QD quality and PL emission efficiency. The greatly improved PL intensity, reduced linewidth, shortened radiative lifetime, with increasing annealing temperature were demonstrated, and InAs/InGaAsSb QDs exhibited enhanced optical characteristics for long-wavelength emission applications.
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Two quantum control spectroscopic techniques were applied to study InAs quantum dot (QD) devices, which contain different strain-reducing layers. By adaptively control light matter interaction, a delayed resonant response from the InAs QDs was found to be encoded into the optimal phase profile of ultrafast optical pulse used. We verified the delayed resonant response to originate from excitons coupled to acoustic phonons of InAs QDs with two-dimensional coherent spectroscopy. Our study yields valuable dynamical information that can deepen our understanding of the coherent coupling process of exciton in the quantum-confined systems.
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On the basis of lanthanide metalloligands, [Ln(ODA)3](3-) (H2ODA = oxydiacetic acid), three series of d-f heterometallic metal-organic frameworks, {[Co(H2O)6]·[Ln2(ODA)6Co2]·6H2O}n [1; Ln = Gd (1a), Dy (1b), and Er (1c)], {[Ln2(ODA)6Cd3(H2O)6]·mH2O}n [2; Ln = Pr (2a), Nd (2b), Sm (2c), Eu (2d), and Dy (2e), m = 9, 6, or 3], and {[Cd(H2O)6]·[Ln2(ODA)6Cd2]·mH2O}n [3; Ln = Dy (3a), Ho (3b), Er (3c), Tm (3d), and Lu (3e), m = 6 or 12], were designed and synthesized by a solvent volatilization and hydrothermal method. Magnetic investigation of 1 reveals the ferromagnetic interactions between the metal ions. In 2, Ln(III) ions occupied the inversion centers, which are confirmed by the fact that the emission intensity ratio of (5)D0 â (7)F1 to (5)D0 â (7)F2 of the Eu(III) ion is much more than 3 in 2d. It is worth noting that, in 2d, the intensity ratio I((5)D0â(7)F1)/I((5)D0â(7)F2) could decrease significantly upon the introduction of different hydrophilic guest molecules, which implies that the luminescent properties of 2d have a strong dependence on the geometry of the first coordination sphere of the Eu(III) ion.
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A novel "turn-on" phosphorescent chemodosimeter based on a cyclometalated Ir(III) complex has been designed and synthesized, which displays high selectivity and sensitivity toward Hg(2+) in aqueous media with a broad pH range of 4-10. Furthermore, by time-resolved photoluminescence techniques, some interferences from the short-lived background fluorescence can be eliminated effectively and the signal-to-noise ratio of the emission detection can be improved distinctly by using the chemodosimeter. Finally, the chemodosimeter can be used to monitor Hg(2+) effectively in living cells by confocal luminescence imaging.
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Complejos de Coordinación/química , Iridio/química , Mediciones Luminiscentes , Mercurio/análisis , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Relación Dosis-Respuesta a Droga , Humanos , Concentración de Iones de Hidrógeno , Estructura Molecular , Teoría Cuántica , Relación Estructura-Actividad , Factores de Tiempo , Células Tumorales CultivadasRESUMEN
X-ray diffraction was used to study the optoelectronic characteristics of Ga-doped TiZnO (GTZO) thin film and revealed increased crystallinity with annealing temperatures ranging from as-grown to 450 °C. The low thin film resistivity of 6.1 × 10(-4) Ω cm and the average high optical transmittance of 93% in the wavelength range between 350 and 800 nm make GTZO an alternative candidate for application in organic light-emitting diodes (OLEDs). Both GTZO and indium-tin-oxide (ITO) anodes are employed for the successful fabrication of blue, green, and red phosphorescent OLEDs. The similar device electrical characteristics observed could be interpreted as evidence of the effectiveness of doping Ga in TiZnO. The simplified tri-layer blue, green, and red phosphorescent OLEDs demonstrated high performance with respective maximum efficiencies of 19.0%, 14.5%, and 9.1%, representing an improvement over ITO-based OLEDs. Furthermore, the OLEDs with the GTZO anode exhibited superior performance at higher current densities, demonstrating high potential for OLED display and lighting applications.
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Framework-isomeric three-dimensional (3D) Cd-Ln heterometallic metal-organic frameworks (HMOFs), {[Ln2 (ODA)6 Cd3 (H2 O)6 ]â 6 H2 O}n (Ln=Gd (1 a) and Tb (1 b), ODA=oxydiacetic acid) and {[Cd(H2 O)6 ]â [Ln2 (ODA)6 Cd2 ]â H2 O}n (Ln=Gd (2 a), Tb (2 b)), with neutral and anionic pores, respectively, were designed based on a lanthanide metalloligand strategy and synthesized by using a stepwise assembly and a hydrothermal method. Luminescence studies revealed that 1 b and 2 b can act as luminescent metal-organic frameworks and their light-emitting properties can be modulated by small guest molecules and the manganese counterion, respectively.
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Cadmio/química , Elementos de la Serie de los Lantanoides/química , Luminiscencia , Compuestos Organometálicos/síntesis química , Aniones/química , Cristalografía por Rayos X , Mediciones Luminiscentes , Modelos Moleculares , Compuestos Organometálicos/química , EstereoisomerismoRESUMEN
To explore the relationship between the structure of the ligands and the luminescent properties of the lanthanide complexes, luminescent lanthanide complexes of a new tripodal ligand, featuring N-thenylsalicylamide arms, were synthesized and characterized by elemental analysis, IR and TGA measurements. Photophysical properties of the complexes were studied by means of UV - visible absorption and steady-state luminescence spectroscopy. The results of UV - vis spectra indicate that metal binding does not disturb the electronic structure of the ligand. Excited-state luminescence lifetimes and quantum yields of the complexes were determined. The photoluminescence analysis suggested that there is an efficient ligand - Ln(III) energy transfer for the Tb(III) complex, and the ligand is an efficient 'antenna' for Tb(III). From a more general perspective, the results demonstrated the potential application of the lanthanide complex as luminescent materials in material chemistry.
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Técnicas de Química Sintética/métodos , Elementos de la Serie de los Lantanoides/química , Luminiscencia , Transferencia de Energía , Elementos de la Serie de los Lantanoides/síntesis química , Ligandos , Estructura Molecular , Nitratos/química , Salicilamidas/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Terbio/química , Terbio/metabolismoRESUMEN
Aluminum nitride (AlN) thin-film materials possess a wide energy gap; thus, they are suitable for use in various optoelectronic devices. In this study, AlN thin films were deposited using radio frequency magnetron sputtering with an Al sputtering target and N2 as the reactive gas. The N2 working gas flow rate was varied among 20, 30, and 40 sccm to optimize the AlN thin film growth. The optimal AlN thin film was produced with 40 sccm N2 flow at 500 W under 100% N2 gas and at 600 °C. The films were studied using X-ray diffraction and had (002) phase orientation. X-ray photoelectron spectroscopy was used to determine the atomic content of the optimal film to be Al, 32%; N, 52%; and O, 12% at 100 nm beneath the surface of the thin film. The film was also investigated through atomic force microscopy and had a root mean square roughness of 2.57 nm and a hardness of 76.21 GPa. Finally, in situ continual sputtering was used to produce a gallium nitride (GaN) layer on Si with the AlN thin film as a buffer layer. The AlN thin films investigated in this study have excellent material properties, and the proposed process could be a less expensive method of growing high-quality GaN thin films for various applications in GaN-based power transistors and Si integrated circuits.
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The multifunctional theranostic nanoplatform based on the combination of persistent luminescent nanoparticles (PLNPs) and metal-organic frameworks (MOFs) has both in vivo imaging and tumor therapeutic drug-loading functions, providing a new strategy for accurate and effective tumor diagnosis and treatment. Herein, the near-infrared (NIR) PLNP SiO2@Zn1.05Ga1.9O4:Cr was combined with HKUST-1 MOFs to form a core-shell structure theranostic nanoplatform which possessed the triple function of autofluorescence-free NIR PersL bioimaging, tumor chemodynamic therapy (CDT), and tumor photothermal therapy (PTT). Also, the photothermal conversion efficiency reached 58.7%, which is superior to the reported nano metal-organic framework (NMOF) photothermal reagents. We demonstrated that the nanoplatform could enter the tumors of mice within 0.5 h and could be target-activated by H2O2 and H2S in the tumor cells, resulting in effective PTT and CDT synergistic treatment. Tumor-bearing mice experiments showed that the tumor could be completely cured without harming normal tissue. This theranostic nanoplatform may provide a promising strategy showing imaging, PTT, and CDT synergistic treatment tri-mode for clinical cancer therapy.
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Nanopartículas , Neoplasias , Animales , Línea Celular Tumoral , Peróxido de Hidrógeno/uso terapéutico , Luminiscencia , Estructuras Metalorgánicas , Ratones , Nanopartículas/química , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Fototerapia , Terapia Fototérmica , Dióxido de Silicio/farmacología , Nanomedicina TeranósticaRESUMEN
A compact low beat-frequency dual-polarization distributed Bragg reflector (DBR) fiber laser whose beat frequency can be varied, for high-frequency ultrasound detection has been proposed and experimentally demonstrated. The laser was fabricated in small birefringent commercial erbium-doped fiber. It operated in a robust single-longitude mode with output power of more than 1 mW and high signal-to-noise ratio better than 60 dB. Induced birefringence to the fiber during the UV inscription process is small (~10(-7)) and consequently the laser beats at a low frequency of ~20 MHz which is at least one order of magnitude smaller than previously reported results, making frequency down-conversion unnecessary. The beat frequency can be adjusted by controlling the side-exposure time of the UV light irradiating the gain cavity, providing a simple approach to multiplex a large number of DBR fiber lasers of different frequencies in series using frequency division multiplexing (FDM) technique. The proposed DBR fiber laser is also temperature insensitive, making it a good candidate for hydrophone applications.
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Tecnología de Fibra Óptica/instrumentación , Rayos Láser , Refractometría/instrumentación , Telecomunicaciones/instrumentación , Transductores , Ultrasonografía/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Erbio/química , MiniaturizaciónRESUMEN
Apricot (Prunus armeniaca L.) cultivars originated in China display a typical S-RNase-based gametophytic self-incompatibility (GSI). 'Katy', a natural self-compatible cultivar belonging to the European ecotype group, was used as a useful material for breeding new cultivars with high frequency of self-compatibility by hybridizing with Chinese native cultivars. In this work, the pollen-S genes (S-haplotype-specific F-box gene, or SFB gene) of 'Katy' were first identified as SFB1 and SFB (8), and the S-genotype was determined as S1 S8. Genetic analysis of 'Katy' progenies under controlled pollination revealed that the stylar S1-RNase and S8-RNase have a normal function in rejecting wild-type pollen with the same S-haplotype, while the pollen grains carrying either the SFB1 or the SFB8 gene are both able to overcome the incompatibility barrier. However, the observed segregation ratios of the S-genotype did not fit the expected ratios under the assumption that the pollen-part mutations are linked to the S-locus. Moreover, alterations in the SFB1 and SFB8 genes and pollen-S duplications were not detected. These results indicated that the breakdown of SI in 'Katy' occurred in pollen, and other factors not linked to the S-locus, which caused a loss of pollen S-activity. These findings support a hypothesis that modifying factors other than the S-locus are required for GSI in apricot.
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Polen/genética , Prunus/genética , Prunus/fisiología , Autofecundación/fisiología , Mutación , Proteínas de Plantas/genética , Polen/fisiología , Ribonucleasas/genética , Autofecundación/genéticaRESUMEN
Solid complexes of terbium and europium nitrates with an amino-alkenone type ligand, 1-[2-(6-methylpyridin-2-ylamino)-5,6-dihydro-4H-pyran-3-yl]ethanone (L) have been prepared and characterized by elemental analysis, conductivity measurements, and IR spectra. The crystal and molecular structures of the complexes [TbL(2)(NO(3))(3)(H(2)O)]·CHCl(3) (1) and [EuL(2)(NO(3))(3)(H(2)O)]·CH(3)CO(2)C(2)H(5) (2) have been determined by single crystal X-ray diffraction. And the coordination spheres of the complexes are similar. At the same time, the luminescent properties of the Tb(3+) complex in solid state and in solvents were investigated at room temperature. Under the excitation of UV light, Tb(III) complex exhibited characteristic emissions but not for the Eu(III) complex. The lowest triplet state energy level of the ligand in the complex matches better to the resonance level of Tb(III) than Eu(III) ion.
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Alquenos/química , Europio/química , Terbio/química , Cristalografía por Rayos X , Ligandos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Rayos UltravioletaRESUMEN
In the title complex, [Cu(C(20)H(13)N(2)O)(2)], the Cu(II) ion is tetra-coordinated by an N(2)O(2) set of two ligands in a distorted recta-ngular-planar geometry. The dihedral angle between the two coordinated five-membered metalla rings is 37.5â (3)°. The mol-ecular configuration is stabilized by two C-Hâ¯O and two C-Hâ¯N intra-molecular hydrogen bonds. The crystal packing is dominated by van der Waals inter-actions. Three atoms of the phenyl ring of the benzohydrazidate moiety are disordered over two sets of sites in a 0.625â (18):0.375â (18) ratio.
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BACKGROUND: Acute myocarditis is an acute myocardium injury that manifests as arrhythmia, dyspnea, and elevated cardiac enzymes. Acute myocarditis is usually caused by a viral infection but can sometimes be caused by autoimmunity. Graves' disease is an autoimmune disease that is a rare etiology of acute myocarditis. Accelerated junctional rhythm is also a rare manifestation of acute myocarditis in adults. CASE SUMMARY: A rare case of new-onset Graves' disease combined with acute myocarditis and thyrotoxic periodic paralysis is reported. The patient was a 25-year-old young man who suddenly became paralyzed and felt palpitations and dyspnea. He was then sent to our emergency department (ED). Upon arrival, electrocardiography revealed an accelerated junctional rhythm and ST-segment depression in all leads, and laboratory findings showed extreme hypokalemia and elevated troponin I, with the troponin I level being 0.32 ng/mL (reference range, 0-0.06 ng/mL). Coronary computer tomography angiography was performed, and there were no abnormal findings in the coronary arteries. Subsequently, the patient was admitted to the ED ward, where further testing revealed Graves' disease, along with continued elevated cardiac enzyme levels and B-type natriuretic peptide (BNP) levels. The troponin I level was 0.24 ng/mL after admission. All of the echocardiography results were normal: Left atrium 35 mm, left ventricle 48 mm, end-diastolic volume 102 mL, right atrium 39 mm × 47 mm, right ventricle 25 mm, and ejection fraction 60%. Cardiac magnetic resonance was performed on the fifth day of admission, revealing myocardial edema in the lateral wall and intramyocardial and subepicardial late gadolinium enhancement in the lateral apex, anterior lateral, and inferior lateral segments of the ventricle. The patient refused to undergo an endomyocardial biopsy. After 6 d, the patient's cardiac enzymes, BNP, potassium, and electrocardiography returned to normal. After the patient's symptoms were relieved, he was discharged from the hospital. During a 6-mo follow-up, the patient was asymptomatic and subjected to thyroid function, liver function, kidney function, troponin I, and electrocardiograph routine tests for medicine adjustments. The hyperthyroid state was controlled. CONCLUSION: Acute myocarditis is a rare manifestation of Graves' disease. Accelerated junctional rhythm is also a rare manifestation of acute myocarditis in adults. When the reason for hypokalemia and elevated cardiac enzymes in patients is unknown, cardiologists should consider Graves' disease and also pay attention to accelerated junctional rhythm.
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In this study, high-performance indium-gallium-zinc oxide thin-film transistors (IGZO TFTs) with a dual-gate (DG) structure were manufactured using plasma treatment and rapid thermal annealing (RTA). Atomic force microscopy measurements showed that the surface roughness decreased upon increasing the O2 ratio from 16% to 33% in the argon-oxygen plasma treatment mixture. Hall measurement results showed that both the thin-film resistivity and carrier Hall mobility of the Ar-O2 plasma-treated IGZO thin films increased with the reduction of the carrier concentration caused by the decrease in the oxygen vacancy density; this was also verified using X-ray photoelectron spectroscopy measurements. IGZO thin films treated with Ar-O2 plasma were used as channel layers for fabricating DG TFT devices. These DG IGZO TFT devices were subjected to RTA at 100 °C-300 °C for improving the device characteristics; the field-effect mobility, subthreshold swing, and ION/IOFF current ratio of the 33% O2 plasma-treated DG TFT devices improved to 58.8 cm2/V·s, 0.12 V/decade, and 5.46 × 108, respectively. Long-term device stability reliability tests of the DG IGZO TFTs revealed that the threshold voltage was highly stable.