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In this paper, the multiferroic BeFiO3 monolayer and NiTiO3–BiFeO3 bilayer thin films were fabricated by spin-coating method on the SrRuO3/n+-Si substrate. The structural and ferroelectric properties of multiferroic BeFiO3 monolayer and NiTiO3–BiFeO3 bilayer thin films were investigated. Both multiferroic films showed the typical XRD patterns of the perovskite structure without presence of the second phase. The electrical properties, such as leakage current and remnant polarization, of the NiTiO3–BiFeO3 bilayer film were superior to those of BeFiO3 monolayer film, which those values were 1.94 × 10−4 A/cm2 at electric field of 0.75 MV/cm and 14.05 μC/cm2, respectively. This outcome is due to the NiTiO3–BiFeO3 bilayer film with a high Schottky barrier height as well as a top NiTiO3 layer on the BiFeO3 film inducing the strain-induced polarization rotation and forming the strong domain-wall pinning.

In this letter, a room-temperature synthesized amorphous indium-zinc oxide (InZn x O y ) sensing membrane on flexible polyimide is employed as an extended-gate field-effect transistor (EGFET) pH sensor for the first time. The InZn x O y -based EGFET sensor exhibited a high pH sensitivity of 56.29 mV/pH with an excellent linearity of 0.999. Furthermore, it also demonstrated good stability in terms of a low hysteresis voltage of 4.6 mV and a small drift rate of 2.08 mV/h, presumably suggesting the formation of uniform, dense, small grains, and stoichiometric InZn x O y thin film, which facilitates high conductivity and provides a large number of surface binding sites. The InZn x O y -based EGFET pH sensor showed an excellent mechanical bendability after more than 500 bending cycles.

In this work, we developed YbTaxOy sensing membranes displaying super-Nernstian pH-sensitivity for use in electrolyte–insulator–semiconductor (EIS) pH sensors. We examined the effect of tantalum content on the structural properties and sensing characteristics of the YbTaxOy sensing membranes deposited through reactive co-sputtering onto Si substrates. X-ray diffraction, atomic force microscopy, secondary ion mass spectrometry, and X-ray photoelectron spectroscopy revealed the structural, morphological, depth, and chemical features, respectively, of these YbTaxOy films prepared under various Ta plasma power conditions (from 80 to 160 W). Among the tested systems, the YbTaxOy EIS device prepared at the 120 W condition exhibited the super-Nernstian sensitivity (70.24 mV/pH), the lowest hysteresis voltage (1.5 mV), and the lowest drift rate (0.26 mV/h). Presumably, this condition optimized the stoichiometry of YbTaO4 in the film and its surface roughness while reducing the crystal defect and suppressing silicate formation at the YbTaxOy–Si interface. The super-Nernstian pH-sensitivity may be attributed to the incorporation of Ta ions in the Yb2O3 forming a YbTaO4 stoichiometric film, enhancing a change in oxidation state of Yb from trivalent ion to bivalent ion and thus transferring one electron to two protons in the redox reaction.

In this work, a super-Nernstian pH sensitivity of TbTaO4 sensing film was developed for an electrolyte-insulator-semiconductor (EIS) solid-state pH sensor. The TbTaO4 sensitive films deposited on the Si substrates through radio-frequency magnetron co-sputtering were prepared under three various Ta plasma powers (80, 120, and 160 W) and then annealed at 800 °C. To investigate the impact of tantalum plasma power, multiple material analyses including X-ray diffraction, secondary ion mass spectrometry, atomic force microscopy, and X-ray photoelectron spectroscopy were performed. Results indicate that the film processed with the 120 W condition might form a stoichiometric TbTaO4 structure and possess a rough surface. Therefore, the best sensing performance was observed for the TbTaO4-based EIS sensor fabricated at the 120 W. In addition, the TbTaO4-based EIS also showed good selectivity for H+ ion over other ions (Na+, K+, Mg2+, and Ca2+). The proposed film fabrication process and analysis may represent a promising approach for the exploration of a novel pH-sensitive TbTaO4 film.

This study aims to investigate the super Nernstian pH sensitivity of Ce2-xSrx(Zr0.53Ti0.47)Oy (CSZT) electrolyte-insulator-semiconductor (EIS) sensors with excess cerium content as a novel solid state device which can be used for detection of pH. We employed the X-ray diffraction, atomic force microscopy, X-ray photoelectron spectroscopy, and field-emission transmission electron microscopy to characterize the structural, morphological, chemical, and microstructural features, respectively, of these films as a function of the growth condition (strontium doping concentrations varied from 0, 5, 10, and 15%). The CSZT EIS device treated at the 10 mol% Sr condition exhibited the highest sensitivity of 93.15 mV/pH, the lowest hysteresis voltage of 1 mV, and the smallest drift rate of 0.32 mV/h among these conditions. This result may be attributed to the optimal Sr content in the CSZT creating a high content of Ce3+ ions, producing a higher surface roughness and forming the neutral oxygen vacancies.

In this letter, we compared the structural and sensing properties of CeTiO3 and Ce2TiO5 sensing films for electrolyte–insulator–semiconductor (EIS) pH sensors. The structural behavior of these sensing films was characterized by Auger electron spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. In comparison with CeTiO3 sensing film, the EIS sensor using a Ce2TiO5 sensing film exhibited better sensing performance including higher sensitivity (68.35 mV/pH), lower hysteresis voltage (0.9 mV), and smaller drift rate (0.19 mV/h), presumably suggesting this film possessing a high fraction of Ce3+ and a rough surface.

In this article, we explored the ability of inorganic LaTixOy (LTO) sensing materials grown on bare p-type substrate to be used as a pH electrolyte-insulator-semiconductor (EIS) sensor. Herein, we fabricated the LTO EIS sensors through the sol-gel synthesis technique under the 0.2 M condition with subsequent annealing at 800 °C in O2 ambient for 20 min. In order to avoid the generation of hydration layer of the gate insulator and reduce the formation of La-silicate, we doped Ti into the La2O3. The structural properties, surface morphologies, film micromorphologies, and chemical states of the sensing films have been investigated by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy analyses, respectively. The sol-gel derived La2Ti2O7 sensing film exhibited super Nernstian pH sensitivity of 68.17 mV/pH with a linearity of 0.999. From the reliability point of view, the La2Ti2O7 sensor showed the best long-term stability with a lower drift rate of 0.21 mV/h as well as a smaller hysteresis voltage of 0.7 mV, as compared with other combination of LTO films. This finding behavior might be due to the high Ti content into the La2Ti2O7 film reducing the silicate layer and increasing the surface sites.

In this paper, we investigated the impact of Sr-doping on the structural properties and electrical characteristics of lead zirconate titanate [Pb(Zr 0.52 Ti 0.48 )O 3 , PZT] thin films deposited on RuO 2 electrodes by a sol-gel process and spin-coating technique. We used X-ray diffraction, atomic force microscopy, X-ray photoelectron spectroscopy, and field-emission transmission electron microscopy to explore the structural, morphological, chemical, and microstructural features, respectively, of these films as a function of the growth condition (strontium doping concentrations varied from 1, 3, and 5 mol%). The PZT thin film processed at the 3 mol% Sr exhibited the best electrical characteristics, including a low leakage current of 2.27×10 −7 A/cm 2 at an electric field of 50 kV/cm, a large capacitance value of 2.74 μF/cm 2 at a frequency of 10 kHz, and a high remanent polarization of 37.95 μC/cm 2 at a frequency of 5 kHz. We attribute this behavior to the optimal amount of strontium in the PZT film forming a perovskite structure and a thicker interfacial layer at the PSZT film-RuO 2 electrode interface.

In this brief, the structural properties and sensing characteristics of spin-coated Ce2(Zr1–xTix)Oy (CZT) sensing film were investigated for electrolyte–insulator–semiconductor (EIS) pH sensors. A higher pH sensitivity of 64.42 mV/pH, a lower hysteresis voltage of 1.1 mV, and a smaller drift rate of 0.36 mV/h were achieved in the CZT-embedded EIS sensors at Zr/Ti = 53/47 stoichiometry. The higher sensing behavior in CZT is attributed to the good crystallization and higher surface roughness of the film.

We investigated the structural and electrical properties of Pb(Zr 0.52 Ti 0.48 )O 3 thin film using sol-gel spin coating method. The crystalline, structural, compositional, and morphological features of Pb(Zr 0.52 Ti 0.48 )O 3 film were studied by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy, and atomic force microscopy, respectively. The relationship between the coercive field (E c ) and frequency (f) is a simple power-law, E c (f) ∝ f β , where β is the frequency coefficient. The β is zero in the Pb(Zr 0.52 Ti 0.48 )O 3 capacitor, indicating the coercive field independence of frequency. This result may be attributed to Pb(Zr 0.52 Ti 0.48 )O 3 thin film possessing the morphotropic phase boundary (MPB) with the coexistence of the tetragonal and rhombohedral phases. The MPB can reduce the domain wall energy to minimize the domain wall movement, and thus decreasing the resistance force acting on the domains.

In this paper, we investigated the effect of In and Zn content on the structural properties and electrical characteristics of amorphous indium–zinc–tin oxide ( $\alpha $ -InZnSnO) thin-film transistors (TFTs) featuring an Yb2TiO5 gate dielectric. The Yb2TiO5 $\alpha $ -InZnSnO TFT prepared at the 30-W condition exhibited better electrical characteristics in terms of a low threshold voltage of 0.52 V, a high ${I}_{{ \mathrm{\scriptscriptstyle ON}}}/{I}_{{ \mathrm{\scriptscriptstyle OFF}}}$ ratio of $1.1\times 10^{8}$ , a low subthreshold swing of 203 mV/decade, and a large field-effect mobility of 27.9 cm2/Vs. We attribute these results to the optimal Zn and Sn content on InZnSnO channel forming a smooth surface and thus reducing density of interface states at the oxide/channel interface.

In this letter, we investigated the impact of Ti content on structural properties and electrical characteristics of high- ${\mathsf \kappa }$ Yb2TiO5 gate dielectrics for amorphous indium–zinc–tin-oxide ( $\alpha $ -IZTO) thin-film transistor (TFT) devices. The Yb2TiO5 $\alpha $ -IZTO TFT device treated at the 120 W condition exhibited excellent electrical characteristics in terms of a low threshold voltage of 0.14 V, high field-effect mobility of 29.8 cm2/Vs, high ION/IOFF current ratio of $2.7\times 10^{8}$ , and small subthreshold swing of 202 mV/decade.

Acentric and nonpolar $\mathrm{P}{\mathrm{b}}_{2}\mathrm{Mn}{\mathrm{O}}_{4}$ was predicted to exhibit unique multipiezo induced magnetoelectric (ME) phenomena. In this paper, we present the results of magnetization as well as dielectric properties as a function of temperature (T), magnetic field (H), pressure (P), and electric field (E) primarily to address the ME coupling and identify the underlying mechanism behind this phenomenon. Magnetization and specific-heat measurements reveal the antiferromagnetic ordering of $\mathrm{M}{\mathrm{n}}^{4+}$ spins at temperature ${T}_{N}=17\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. Metamagnetic transitions at three critical magnetic fields (${H}_{c1}$, ${H}_{c2}$, and ${H}_{c3}$) are observed for T ${T}_{N}$ and H g 3.5 T. Further, the influences of pressure and magnetic field on ${H}_{c1}$ and ${H}_{c2}$ are investigated. The ${T}_{N}$, ${H}_{c1}$, and ${H}_{c2}$ all decrease with increasing external pressure. The dielectric anomaly observed at ${T}_{N}$ is influenced by applying a magnetic field of H g 3.5 T. However, the electric field has minimal influence on the metamagnetic transition. The scaling between dielectric constant and magnetization meaningfully resolves the existence of magnetic-field-induced higher-order ME coupling in $\mathrm{P}{\mathrm{b}}_{2}\mathrm{Mn}{\mathrm{O}}_{4}$ at T ${T}_{N}$ and H g 3.5 T.

In this study, we studied the structural properties and ferroelectric characteristics of the pure BeFiO3 (BFO) and mixed NiTiO3-BiFeO3 (NTO-BFO) thin films by the sol-gel method and spin-coating process. We employed atomic force microscopy, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, X-ray diffraction, and transmission electron microscopy to analyze the surface roughness, chemical bonding, surface morphology, crystal structure, and film microstructure of both thin films. The mixed NTO-BFO film showed better electrical characteristics, such as a smaller leakage current density (9.66 × 10−5 A/cm2) and a higher remanent polarization (59.02 μC/cm2), than the pure BFO one. Moreover, the mixed film demonstrated diamagnetism behavior in the magnetic-hysteresis loop. This finding may be attributable to the NTO film deposited on the BFO film avoiding the volatilization of Bi ions and increasing the domain walls, hence giving rise to a decreased leakage current and an increased ferroelectric characteristic.

This paper describes the effect of titanium content on the structural and electrical properties of ErTi x O y charge storage layers in amorphous indium–gallium–zinc oxide ( $\alpha $ -IGZO) thin-film transistor (TFT) nonvolatile memory (NVM) devices. X-ray diffraction, Auger electron spectroscopy, and X-ray photoelectron spectroscopy were used to study the film structural, depth profiling, and chemical features, respectively, of these films as the functions of the growth conditions (Ti plasma powers of 60, 100, and 140 W). The ErTi x O y IGZO TFT NVM devices fabricated at the 100-W condition exhibited a larger memory window of 4.1 V, a smaller charge loss of 13% (after ten years), and a better endurance characteristic (up to $10^{5}$ program/erase cycles), as compared with other conditions. This result suggests that the Er2TiO5 film featuring a high dielectric constant and reducing an Er(OH) x layer can provide the higher charge-trapping efficiency and deeper electron trapping levels.

In this paper, we developed high-performance InGaZnO thin-film transistors (TFTs) using three stacked TbTixOy, ErTixOy and YbTixOy/PbZr0.53Ti0.47O3 (PZT) gate dielectrics by rf-sputtering method. The structural properties of stacked TbTixOy, ErTixOy and YbTixOy/PZT dielectric films were studied. Atomic force microscopy, X-ray photoelectron spectroscopy and X-ray diffraction were used to investigate the morphological, chemical and structural features, respectively, of these dielectric films. The inspected structural properties were related to the effecting electrical performances. The InGaZnO TFT device fabricating the stacked YbTixOy/PZT dielectric exhibited the best electrical characteristics, such as a small subthreshold swing of 68 mV/decade, a low threshold voltage of 3 mV, a large electron mobility of 24.4 cm2/V-s, and a high Ion/Ioff ratio of 5.91 × 109. We attribute this behaviour to the YbTixOy film having a higher κ value as well as a smoother surface.

In this paper, we developed a high-performance YbTixOy/PbZr0.53Ti0.47O3 (PZT) stacked gate dielectric for indium–gallium–zinc-oxide (InGaZnO) thin-film transistor (TFT) devices. X-ray diffraction, atomic force microscopy, and x-ray photoelectron spectroscopy were applied to examine the crystal structure, film morphology, and elemental composition of the YbTixOy and YbTixOy/PZT stacked films, respectively. Compared with the YbTixOy dielectric, the InGaZnO TFT device with the YbTixOy/PZT stacked dielectric exhibited excellent electrical characteristics in terms of a lower subthreshold swing of 77 mV decade−1, a higher Ion/Ioff current ratio of 3.8 × 109, a smaller threshold voltage of 80 mV, and a larger field-effect mobility of 21.2 cm2 V-s−1. These results are attributed to the YbTixOy/PZT stacked film possessing the high-κ value as well as the smooth interface between the channel layer and dielectric.

This work describes the impact of indium content of the structural properties and sensing characteristics of ZnInxOy sensing films for extended-gate field-effect transistor (EGFET) sensors. The synthesis of the ZnInxOy sensing films was made by a solution processing technique directly deposited on flexible polyethylene naphthalate (PEN) through a simple spin-coating method. The synthesized ZnInxOy films at three different indium concentrations (10%, 20% and 30% moles) were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, and atomic force microscopy to examine their chemical features, film structures and surface morphologies, respectively. Experiments were performed to explore the pH sensitivity, drift rate, and hysteresis voltage in the ZnInxOy EGFET sensors. Compare with these conditions, a higher pH sensitivity of 61.76 mV/pH, a lower drift rate of 1.08 mV/h, and a smaller hysteresis voltage of ∼1 mV were obtained in the ZnInxOy EGFET sensor fabricated at the 20% condition. Moreover, after 500 bending cycles, the ZnInxOy EGFET sensor fabricated at the 20% condition showed good mechanical flexibility. The ZnInxOy EGFET sensor also demonstrated a high selective response towards H+. This result indicates that the ZnInxOy sensing film with a rougher surface and a higher Zn–O–In content to generate lower crystal deformities, imperfections and oxygen vacancies.

With the aim of a simple, label-free, and highly specific dopamine detection, we proposed an indium-zinc oxide (InZnxOy) sensing film on flexible PET using a simple sol-gel method for an extended gate field-effect transistor (EGFET) sensor. In this study, X-ray diffraction, atomic force spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the structural, morphological, and chemical features, respectively. The InZnxOy based EGFET sensor showed a super Nernstian pH response of 61.53 mV/pH with an excellent linearity of 0.995 (in the range of pH 2–12), a low hysteresis voltage of ∼ 3 mV (in the pH loop of 7→4→7→10→7) and a small drift rate of 3.52 mV/h (in the pH 7). Correspondingly, to investigate the impact of mechanical bending on the pH performances of InZnxOy based flexible EGFET sensor, a couple of bending tests, which include different bending radius and bending cycles, were performed. The device showed better mechanical durability up to 1500 bending cycles for pH sensitivity. In order to achieve the label-free detection of dopamine, the InZnxOy on PET-based EGFET was functionalized using a synthetic receptor named 4-carboxylphenylboronic acid, for the covalent binding of dopamine on the sensing surface. The sensitivity of dopamine is 10.69 mV/log(dopamine) with linearity 0.998 within the dopamine concentration range of 1 fM–1 nM and the limit of detection value is 0.523 fM. In addition, this InZnxOy based EGFET biosensor showed excellent selectivity to dopamine over other interfering chemicals. Our proposed InZnxOy EGFET biosensor was successfully applied to detect dopamine level in the real samples like rat blood serum and rat brain.

The complementary metal-oxide-semiconductor compatible electrolyte-insulator-semiconductor (EIS) platform is a promising tool for the detection of ions and biomolecules. In this investigation, we fabricated a Y2O3 sensing membrane based EIS pH sensor by Pechini sol-gel method. X-ray diffraction, atomic force microscopy and X-ray photoelectron spectroscopy were implemented to analyze the effect of yttrium concentration (0.1, 0.2 and 0.3 M) on the crystalline structure, surface morphology and chemical composition of the sensing membrane, respectively. The Y2O3 based EIS sensor fabricated under the 0.2 M concentration manifests the near-super-Nernstian pH response (63.80 mV/pH) and high stability in terms of a low hysteresis voltage (5.7 mV) and a small drift rate (0.18 mV/h). We ascribe that the optimal yttrium content increases the surface roughness of the sensing membrane and the formation of a well-crystallized Y2O3 film as well as a stoichiometric Y2O3 film.

In this paper, we developed a high-performance solid-state pH sensor using a Ce

In this study we developed ytterbium tantalum oxide (YbTaO4) sensing membranes for use in electrolyte–insulator–semiconductor (EIS) pH sensors. The influence of rapid thermal annealing (RTA) treatment on the sensing and impedance properties of the YbTaO4 sensing membranes deposited through reactive co-sputtering onto Si substrates was explored. X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy revealed the structural, morphological, and chemical features, respectively, of these YbTaO4 films annealed at 700, 800 and 900 °C. The YbTaO4 EIS device annealed at the 800 °C exhibited a super-Nernstian response of 71.17 mV/pH within the pH range of 2–12. It also showed the lowest hysteresis voltage (

In this brief, a high-performance amorphous InGaZnO ( $\alpha $ -IGZO) thin-film transistor (TFT) with a HfO2/Lu2O3/HfO2 (HLH) sandwich gate dielectric is demonstrated for the first time. Compared with the Lu2O3 dielectric, the $\alpha $ -IGZO TFT device using an HLH sandwich gate dielectric exhibited a low threshold voltage of 0.43 V, a high field-effect mobility of 17.2 cm $^{2}$ /Vs, a small subthreshold swing of 104 mV/decade, and a high $I_{\rm {ON}} / I_{\rm {OFF}}$ current ratio of $3.08\times 10^{7}$ , presumably because of the reduction of surface roughness at the dielectric–channel interface. Furthermore, the reliability of voltage stress can be improved using an HLH sandwich dielectric structure.

In this paper, we developed high- $\kappa$ $\hbox{Yb}_{2}\hbox{O}_{3}$ and $\hbox{YbTi}_{\rm x}\hbox{O}_{\rm y}$ gate dielectrics for an amorphous indium-gallium-zinc oxide ( $\alpha$ -IGZO) thin-film transistor (TFT) applications. Compared with the $\hbox{Yb}_{2}\hbox{O}_{3}$ dielectric, the $\alpha$ -IGZO TFT using the high- $\kappa$ $\hbox{YbTi}_{\rm x}\hbox{O}_{\rm y}$ gate dielectric exhibited better electrical characteristics, such as a high ${\rm I}_{\rm on}/{\rm I}_{\rm off}$ ratio of $4.5\times 10^{7}$ , a high field-effect mobility of $26.1\ \hbox{cm}^{2}/\hbox{V-s}$ , a low threshold voltage of 0.53 V, and a low subthreshold swing of 210 mV/decade. These results are probably due to the incorporation of Ti into the $\hbox{Yb}_{2}\hbox{O}_{3}$ film, resulting in the formation of smooth surface and low density of interface states at the oxide/channel interface. Furthermore, the stability of high- $\kappa$ $\hbox{Yb}_{2}\hbox{O}_{3}$ and $\hbox{YbTi}_{x}\hbox{O}_{y}$ $a$ -IGZO TFTs was investigated under both positive bias stress and negative bias stress conditions.

In this study, we report the structural and electrical characteristics of high-κ Sm2O3 and SmTiO3 charge trapping layers on an indium–gallium–zinc oxide (IGZO) thin-film transistor (TFT) for non-volatile memory device applications. The IGZO TFT non-volatile memory featuring a SmTiO3 charge trapping layer exhibited better characteristics, including a larger memory window (2.7 V), long charge retention time (105 s with charge loss

In this letter, we investigate the structural and electrical characteristics of Er2O3 and ErTi x O y charge-trapping layers for InGaZnO thin-film transistor (TFT) nonvolatile memory devices for the first time. Compared with the Er2O3 layer, the InGaZnO TFT memory device incorporating the ErTi x O y charge-trapping layer exhibited a lower subthreshold swing of 146 mV/decade, a larger memory window of 3.9 V, a smaller charge loss of 10%, and better endurance performance for program/erase cycle up to $10^{5}$ , presumably due to the high charge efficiency in the ErTi x O y film.

In this article, we studied the structural properties and electrical characteristics of GdTiO3 gate dielectric for amorphous indium–gallium–zinc oxide (a-IGZO) thin-film transistor (TFT) applications. The a-IGZO TFT device featuring the GdTiO3 gate dielectric exhibited better electrical characteristics, including a small threshold voltage of 0.14 V, a large field-effect mobility of 32.3 cm2/V-s, a high Ion/Ioff current ratio of 4.2 × 108, and a low subthreshold swing of 213 mV/decade. Furthermore, the electrical instability of GdTiO3 a-IGZO TFTs was investigated under both positive gate-bias stress (PGBS) and negative gate-bias stress (NGBS) conditions. The electron charge trapping in the gate dielectric dominates the PGBS degradation, while the oxygen vacancies control the NGBS degradation.

In this paper, we compared the structural and electrical properties of high- κ Gd2O3 and GdTiO3 gate dielectrics for an amorphous indium-gallium-zinc oxide ( α-IGZO) thin-film transistor (TFT) application. In comparison with the Gd2O3 dielectric, the α-IGZO TFT featuring the GdTiO3 dielectric exhibited better electrical characteristics in terms of a large field effect mobility of 26.9 cm2/Vs, a low threshold voltage of 0.04 V, a high ION/IOFF ratio of 1.2×108, and a low subthreshold swing of 200 mV/decade. We attribute these results to the incorporation of Ti into the Gd2O3 film, forming a smooth surface and thus reducing density of interface states at the oxide/channel interface. In addition, the stability of threshold voltage on high- κ Gd2O3 and GdTiO3 a-IGZO TFTs was studied under positive gate bias stress.

In this paper, we fabricated a sol-gel derived RuOx, with low-temperature thermal oxidation, on polyethylene terephthalate (PET) flexible based extended-gate field-effect transistor (EGFET) as a pH sensor for the assessment of glucose for the first time. Structural identification, surface morphology, and film composition of the sensing membrane were investigated by X-ray diffraction, atomic force microscopy, and X-ray photoelectron microscopy, respectively. The RuOx on PET based EGFET sensor exhibited a pH sensitivity of 65.11 mV/pH in the wide range of pH 2–12 with an excellent linearity of 0.999. This sensor showed good reversibility in terms of a lower hysteresis voltage of ∼1 mV and a better stability for 12 h named as drift rate ∼2.08 mV/h. The RuOx-based EGFET sensor also demonstrated a high selective response towards H+. In addition, the pH performace of this RuOx EGFET flexible sensor kept unchanged after 500 repeated bending cycles. Subsequently, the RuOx on PET based EGFET was functionalized by 4-carboxyphenyl boronic acid (4-CPBA), which is a synthetic receptor for covalent attachment of glucose on the sensing surface. The sensitivity of glucose was 6.89 mV/mM with the linearity of 0.993 within the glucose concentration from 1 to 8 mM. The concentration of serum glucose measured by our 4-CPBA functionalized RuOx EGFET biosensor is comparable to that determined by commercial blood glucose monitoring system. In addition, this RuOx EGFET biosensor exhibited an elevated reference voltage shift response to glucose compared with other saccharides (e.g. fructose, sucrose and mannose).

In this paper, we developed YbTaO4 sensing membranes for use in a solid-state electrolyte–insulator–semiconductor (EIS) pH sensor. Impact of rapid thermal annealing (RTA) treatment on the structural and sensing properties of the YbTaO4 sensing membranes deposited through reactive co-sputtering onto Si substrates was investigated. X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy were employed to examine the structural, morphological, and chemical features, respectively, of the YbTaO4 sensing films annealed at three RTA temperatures (700, 800 and 900 °C). The YbTaO4 EIS sensor annealed at the 800 °C exhibited a super-Nernstian response of 71.17 mV/pH within the pH range of 2–12. It also showed the lowest hysteresis voltage (4 film and increased its (-131)-oriented nanograin size. Figure 1

In this paper, a high performance CeTixOy sensing film was developed by using a simple sol-gel spin-coating method for an electrolyte-insulator-semiconductor (EIS) pH sensor. The crystal structures, surface morphologies, and chemical compositions of the CeTixOy films prepared under different titanium concentrations (0.1, 0.3 and 0.5 M) were explored using a combination of X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy, respectively. The structural properties of the CeTixOy membranes were associated with the sensing performances of their EIS pH sensors. The CeTixOy sensing film fabricated at the 0.3 M condition exhibited the best sensing characteristics (pH sensitivity, hysteresis voltage and drift rate) among these conditions. We attribute this behavior to the optimal titanium content in the film forming the stoichiometric Ce2TiO5 structure, enhancing the surface roughness CeTixOy film, and increasing the Ce3+/Ce4+ ratio. Figure 1

In this study, we explored the threshold voltage instability behavior in amorphous indium-gallium-zinc oxide (α-IGZO) thin-film transistor (TFT). A tow-step electrical degradation behavior of α-IGZO TFT was found under gate-bias stress. A usual small positive shift followed by a special negative shift of threshold voltage is characterized in the α-IGZO TFT. We suggest that the positive shift of the threshold voltage is because of charge trapping in the gate dielectric and/or at the channel/dielectric interface, while the negative shift of threshold voltage may be attributed to electric field induced extra electron carriers from H2O molecules in the back channel protective layer.

In this paper, we investigated the structural properties and electrical characteristics of high-κ ErTixOy gate dielectrics on indium-gallium-zinc oxide thin-film transistors (IGZO TFTs). We used X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy to investigate the structural and morphological features of these dielectric films after they had been subjected to annealing at various temperatures. The high-κ ErTixOy IGZO TFT device annealed at 400 °C exhibited better electrical characteristics in terms of a large field-effect mobility (8.24 cm2/V-s), low threshold voltage (0.36 V), small subthreshold swing (130 mV/dec), and high Ion/off ratio(3.73 × 106). These results are attributed to the reduction of the trap states and oxygen vacancies between the ErTixOy film and IGZO active layer interface during high-temperature annealing in oxygen ambient. The reliability of voltage stress also can be improved by the oxygen annealing at 400 °C.

In this paper, we developed a low operation voltage and a single reaction step of a graphene field-effect transistor (GFET) biosensor device to detect alanine aminotransferase (ALT). The device is fabricated using large-area graphene thin films by means of chemical vapor deposition. The GFET device operated at 0.1 V drain voltage and −0.1 to 0.3 V sweep gate voltage exhibited a high pH sensitivity of 23.12 mV/pH, a low hysteresis voltage of 1.2 mV, and a small drift rate of 4.74 mV/h. In this research, the hybrid configuration of l -alanine and α-ketoglutarate immobilized on the graphene membrane was proved to be able to detect ALT with good linearity (R2 = 0.99) in the ALT concentration range of 10–100 U/L.

We investigated the effect of surface roughness on the electrical characteristics in amorphous indium–gallium–zinc oxide (a-IGZO) thin-film transistors (TFTs) fabricating high- κ Sm 2 O 3 gate dielectrics, prepared under different annealing temperatures. The high- κ Sm 2 O 3 a-IGZO TFT device annealed at 200 °C exhibited better electrical characteristics, including a large field effect mobility of 6.25 cm 2 /V s, small threshold voltage of 0.79 V, low subthreshold swing of 354 mV/decade, and high I on / I off ratio of 3.1×10 7 . These results are attributed to the formation of smooth surface at the oxide/channel interface. Furthermore, the reliability of a Sm 2 O 3 a-IGZO TFT device can be improved by oxygen annealing at low temperature.

The possible neurological and biophysical effects of magnetic fields on animals is an area of active study. Here, we report that courtship activity of male Drosophila increases in a magnetic field and that this effect is regulated by the blue light-dependent photoreceptor cryptochrome (CRY). Naïve male flies exhibited significantly increased courtship activities when they were exposed to a ≥ 20-Gauss static magnetic field, compared with their behavior in the natural environment (0 Gauss). CRY-deficient flies, cryb and crym, did not show an increased courtship index in a magnetic field. RNAi-mediated knockdown of cry in cry-GAL4-positive neurons disrupted the increased male courtship activity in a magnetic field. Genetically expressing cry under the control of cry-GAL4 in the CRY-deficient flies restored the increase in male courtship index that occurred in a magnetic field. Interestingly, artificially activating cry-GAL4-expressing neurons, which include large ventral lateral neurons and small ventral lateral neurons, via expression of thermosensitive cation channel dTrpA1, also increased the male courtship index. This enhancement was abolished by the addition of the cry-GAL80 transgene. Our results highlight the phenomenon of increased male courtship activity caused by a magnetic field through CRY-dependent magnetic sensation in CRY expression neurons in Drosophila.

Resistive random access memory (ReRAM) is an emerging stor-age device for next generation high potential nonvolatile memory(NVM) applications due to its scaling ability, low cost, and com-patibility of being integrated in back-end-of-line (BEOL) process incomplementary metal-oxide-semiconductor (CMOS) fabrication.

In this article, we report the forming-free resistive switching behavior of a Ru/Dy 2 O 3 /TaN memory device incorporating a Dy 2 O 3 thin film fabricated entirely through processing at room temperature. We used X-ray diffraction, secondary ion mass spectrometry, and X-ray photoelectron spectroscopy to investigate the structural and chemical features of the Dy 2 O 3 film. The dominant conduction mechanisms in the low- and high-resistance states were ohmic behavior and Poole–Frenkel emission, respectively. The Ru/Dy 2 O 3 /TaN memory device exhibited a high resistance ratio and provided nondestructive readout and reliable data retention. This memory device has a great potential for application in nonvolatile resistive switching memory.

The structural and electrical properties of Lu2O3 dielectric films deposited by radio frequency (RF) magnetron sputtering on TaN electrode have been studied for metal–insulator–metal (MIM) capacitor in analog/RF applications. From X-ray diffraction study, it is observed that the deposited films remain amorphous within the thermal budget (400◦C) of back-end-of-line process. The root mean square value of surface roughness of the Lu2O3 film decreases after annealing at 400◦C using atomic force microscopy. The chemical composition of the Lu2O3 film was characterized by X-ray photoelectron spectroscopy. The MIM capacitor using a Lu2O3 dielectric film exhibited better electrical characteristics, such as a low leakage current of 5 × 10−8 A/cm2 at −1 V and a high capacitance density of 7.5 fF/μm2 with a low quadratic voltage coefficient of capacitance of 75 ppm/V2. The current conduction mechanism was found to be dominated by Schottky emission mechanism in low electric field (

In this study, we investigated the impact of Ti content on structural properties and electrical characteristics of high-k Yb2TiO5 gate dielectrics for amorphous indium–zinc–tin-oxide (a-InZnSnO) thin-film transistor (TFT) devices. The Yb2TiO5 thin films with different Ti plasma conditions were integrated in metal-insulator-metal structures to check the electrical capabilities. The Yb2TiO5 a-InZnSnO TFT device fabricated at the 120 W condition exhibited excellent electrical characteristics in terms of a small threshold voltage (VTH) of 0.14 V, a low subthreshold swing of 202 mV/decade, a large field-effect mobility of 29.8 cm2/V-s, and a high Ion/Ioff current ratio of 2.7×108. In addition, the VTH stability of Yb2TiO5 a-InZnSnO TFT device was studied under both positive bias stress and negative bias stress conditions. The Yb2TiO5 thin film is a promising gate dielectric material for the fabrication of a-InZnSnO TFTs.

A new series of Te-Ru-Cu carbonyl complexes was prepared by the reaction of K(2)TeO(3) with [Ru(3)(CO)(12)] in MeOH followed by treatment with PPh(4)X (X=Br, Cl) and [Cu(MeCN)(4)]BF(4) or CuX (X=Br, Cl) in MeCN. When the reaction mixture of K(2)TeO(3) and [Ru(3)(CO)(12)] was first treated with PPh(4)X followed by the addition of [Cu(MeCN)(4)]BF(4), doubly CuX-bridged Te(2)Ru(4)-based octahedral clusters [PPh(4)](2)[Te(2)Ru(4)(CO)(10)Cu(2)X(2)] (X=Br, [PPh(4)](2)[1]; X=Cl, [PPh(4)](2)[2]) were obtained. When the reaction mixture of K(2)TeO(3) and [Ru(3)(CO)(12)] was treated with PPh(4)X (X=Br, Cl) followed by the addition of CuX (X=Br, Cl), three different types of CuX-bridged Te-Ru carbonyl clusters were obtained. While the addition of PPh(4)Br or PPh(4)Cl followed by CuBr produced the doubly CuBr-bridged cluster 1, the addition of PPh(4)Cl followed by CuCl led to the formation of the Cu(4)Cl(2)-bridged bis-TeRu(5)-based octahedral cluster compound [PPh(4)](2)[{TeRu(5)(CO)(14)}(2)Cu(4)Cl(2)] ([PPh(4)](2)[3]). On the other hand, when the reaction mixture of K(2)TeO(3) and [Ru(3)(CO)(12)] was treated with PPh(4)Br followed by the addition of CuCl, the Cu(Br)CuCl-bridged Te(2)Ru(4)-based octahedral cluster chain polymer {[PPh(4)](2)(Te(2)Ru(4)(CO)(10)Cu(4)Br(2)Cl(2)).THF}(infinity) ({[PPh(4)](2)[4].THF}(infinity)) was produced. The chain polymer {[PPh(4)](2)[4].THF}(infinity) is the first ternary Te-Ru-Cu cluster and shows semiconducting behavior with a small energy gap of about 0.37 eV. It can be rationalized as resulting from aggregation of doubly CuX-bridged clusters 1 and 2 with two equivalents of CuCl or CuBr, respectively. The nature of clusters 1-4 and the formation and semiconducting properties of the polymer of 4 were further examined by molecular orbital calculations at the B3LYP level of density functional theory.