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The use of zirconia for implants and abutments has become more prevalent in implant dentistry as an alternative to the commonly used titanium implants, and peri-implant disease can still affect them. The erbium, chromium-doped:yttrium-scandium-gallium-garnet (Er, Cr:YSGG) laser has emerged as a promising treatment modality. The purposes of this in vitro study were to (1) determine the effects of the laser on the surface roughness of zirconia discs; (2) determine the extent of removal of a single species biofilm, E. coli, on the zirconia discs after applying the laser; (3) determine the amount of cell adhesion and proliferation utilizing fibroblasts on zirconia discs after treatment with the laser. All treatments will be compared with the commonly used ultrasonic instrumentation and hand scalers. For the first aim, gross examination revealed noticeable surface damage on the discs when using ultrasonic and scalers but not for the laser group. For surface roughness, the mean roughness was Pa= 0.623±0.185 μm, 0.762±0.421 μm, 0.740±0.214 μm, and 0.724±0.168 μm for control discs, and discs treated with either the Er,Cr:YSGG laser, ultrasonic instrumentation, and hand scalers respectively. There was no statistical significance among the groups (p=0.628). For bacteria decontamination, there was a statistical significance among the groups (p< 0.0001). Statistical significance was seen between the control group and each of the three treatment groups, favoring the treatment groups (p< 0.0001). Statistical significance was seen when comparing ultrasonic instrumentation and hand scalers (p= 0.000) as well as when comparing the Er,Cr:YSGG laser to hand scalers (p= 0.007), favoring both the ultrasonic instrumentation and Er,Cr:YSGG laser. No significance between the Er,Cr:YSGG laser group and the ultrasonic instrumentation group was noted (p =0.374). When comparing the cell attachment following treatment in each of the three groups and also without treatment (control), there was a statistical significance among the groups (p

There has been an increase in utilizing 3D printers in dental restorations. The purpose of the study is to compare mechanical properties of 3D-printed prostheses to those of self-cured and/or computer-aided design-computer-aided manufacturing (CAD-CAM) restorations. A metal master typodont was prepared for the mandibular left sextant with implant analogs embedded at the first premolar and first molar positions with a missing second premolar. Three-unit provisional fixed dental prosthesis (FDP) was designed utilizing the 3Shape tooth library and forty-five uniform specimens were fabricated with different materials: self-cured poly(methyl methacrylate) (PMMA) (N = 15), milled PMMA CAD-CAM blocks (N = 15) and 3D-printed resin (N = 15). All specimens were tested using an Instron machine at a crosshead speed of 0.5 mm/min by an axial load on the occlusal surface of the second premolar pontic site. Statistical analysis was completed with Shapiro-Wilk, ANOVA and Tukey post-hoc tests. Mean fracture force was 300.61 N, 294.64 N and 408.49 N for self-cured PMMA, milled PMMA and 3D-printed resin, respectively. Mean force at FDP fracture of 3D-printed resin was significantly greater than the mean fracture force of either self-cured (p = 0.016, 95% CI [17.86, 197.91]) or milled (p = 0.010, 95% CI [23.83, 203.88]) PMMA.

The objective of this study is to evaluate titanium decontamination after different protocols while assessing changes in surface roughness, chemical composition, and wettability.Ninety-six smooth (S) and 96 minimally rough (R) titanium microimplants were used. Pristine microimplants were reserved for negative control (S-nC/R-nC, n = 9), while the remaining microimplants were incubated in Escherichia coli culture. Non-decontaminated microimplants were used as positive control (S-pC/R-pC, n = 3). The other microimplants were divided into seven different decontamination protocols (12 S/R per group): 24% EDTA, 2% chlorhexidine (CHL), gauze soaked in 2% chlorhexidine (GCHL), gauze soaked in ultrapure water (GMQ), scaling (SC), titanium brush (TiB), and implantoplasty (IP). Contaminated areas were assessed by scanning electron microscope images, chemical composition by energy dispersive X-ray spectroscopy, wettability by meniscus technique, and roughness by an optical profiler.Higher residual bacteria were observed in R-pC compared with S-pC (P 0.0001). When comparing S and R with their respective pC groups, the best results were obtained with GCHL, SC, TiB, and IP, with no difference between these protocols (P 0.05). Changes in surface roughness were observed after all treatments, with S/R-IP presenting the smoother and a less hydrophilic surface (P 0.05). Apart from IP protocol, all the other groups presented a more hydrophilic surface in R than in S microimplants (P 0.003). All decontamination protocols resulted in a lower percentage of superficial Ti when compared with S/R-nC (P 0.002).All decontamination protocols resulted in changes in roughness, wettability, and chemical composition, but GCHL, SC, TiB, an IP presented the best decontamination outcomes.

Marine lubricants’ ability of dispersing Heavy Fuel Oil (HFO) can be quantitatively observed and evaluated with an efficient and economic method: heating capillary video microscopy. Effects on HFO ...

This work highlights the fabrication of nickel‑copper/titanium nitride (Ni-Cu/TiN) for the use in direct methanol fuel cells. Ni-Cu nanoparticles are coated on the surface of TiN film by electrochemical methods. The formation of Ni-Cu/TiN is confirmed by a variety of means such as field-emission scanning electron microscopy and atomic force microscopy. The presence of Ni-Cu on TiN film is further confirmed by cyclic voltammetry. For the electrochemical oxidation of methanol, the electrocatalytic activity of the prepared Ni-Cu/TiN is higher than those of Cu/TiN, Ni/TiN, Ni-Mn/TiN, and Ni-Co/TiN. The stability for the electrochemical oxidation of methanol at Ni-Cu/TiN is better than that of Ni-Cu/glassy carbon electrode. The proposed Ni-Cu/TiN might be beneficial to develop high performance and low manufacturing cost of direct methanol fuel cells.

This paper presents the fabrication of polyaniline and graphene oxide aerogel composite (PGA) thin film-based sensors for H2S gas sensing application. The optical and morphological properties of these composite films were characterised correspondingly by UV–visible spectroscopy and scanning electron microscopy. To prepare the gas sensors, thin films of PANI and PGA composites were deposited onto interdigitated electrodes by spin coating method. The response of these sensors towards H2S gas was evaluated by monitoring the change in electrical conductivity at room temperature under two relative humidity values of 60% RH and 80% RH. The PGA composite thin film-based gas sensors showed a higher response compared with the pure PANI-based sensor. The gas sensor made of PGA-3 showed a good response of 3.87 in 67 s (60% RH), which is 4.6 times higher than that of pure PANI and 2.5 times higher than that of PGA-1 at 1 ppm. The first-principles simulations were carried out to investigate the H2S sensing mechanism of PGA heterostructure. The adsorption of H2S at different locations of pure PANI and PGA composites was analysed. The band gap for PGA showed more significant change after adsorption than that of pure PANI, which indicated the higher sensitivity for detecting H2S.

In this study, we developed an overlay coating of high-entropy alloy (HEA) NiCo 0.6 Fe 0.2 Cr 1.5 SiAlTi 0.2 (C3) via atmospheric plasma spraying. The as-deposited coating is a supersaturated BCC phase except some oxide stringers formed during the spray. However, a plenty of Cr 3 Si phase forms in the coating and cause a large increase of hardness and wear resistance when aged at 800 and 1100 °C. The oxidation weight gain test demonstrates that the coating exhibits oxidation resistance as good as typical NiCrAlY coating at 1100 °C due to the formation of a dense thermally grown oxide layer (TGO) comprising Al 2 O 3 and Cr 2 O 3 . This coating becomes a strong candidate for high-temperature protective layer requiring oxidation and wear resistance.

In this work, the effects of nitrous oxide plasma treatment on the negative bias temperature stress of indium tin zinc oxide (ITZO) and indium gallium zinc oxide (IGZO) thin film transistors (TFTs) were reported. ITZO TFTs were more suitable for the back channel etched-type device structure because they could withstand both Al- and Cu-acid damage. The initial threshold voltage range could be controlled to within 1 V. The root cause of poor negative bias temperature stress for ITZO was likely due to a higher mobility (∼3.3 times) and more carbon related contamination bonds (∼5.9 times) relative to IGZO. Finally, 65″ active-matrix organic light-emitting diode televisions using the ITZO and IGZO TFTs were fabricated.

We have investigated the role of temperature in the degradation of GaN High-Electron-Mobility-Transistors (HEMTs) under high-power DC stress. We have identified two degradation mechanisms that take place in a sequential manner: the gate leakage current increases first, followed by a decrease in the drain current. Building on this observation, we demonstrate a new scheme to extract the activation energy (Ea) of device degradation from step-temperature measurements on a single device. The Ea’s we obtain closely agree with those extracted from conventional accelerated life test experiments on a similar device technology.

We reported amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) TFT OLED TV panel development in AUO. The Generation 6 (G6) threshold voltage uniformity can be lower than 0.8V. The RGB side-by-side OLED patterning was realized by fine metal mask. By the application of a source follower connection pixel compensation circuit, the panels driven by AUO engine show excellent characteristics. For future product performance requirement, amorphous Indium-Tin-Zinc-Oxide (a-ITZO) TFT was developing, high mobility as 33.2 cm2/Vs was achieved. Metal-organic chemical vapor deposition (MOCVD) system was also used to improve the mobility of IGZO TFT. To improve manufacturing efficiency of OLED process, inkjet printing technology is also under development in AUO.

Solid and hollow structures of Cu2–xTe nanocrystals are synthesized by the injection of a Te–TOP solution at different reaction times. Both types of Cu2–xTe nanocrystals exhibit an intense absorption peak (localized surface plasmon resonance (LSPR)) in the near-infrared region, arising from excess holes in the valence band, and high molar extinction coefficients of 2.6 × 107 M–1 cm–1 at 1150 nm and 8.1 × 107 M–1 cm–1 at 1200 nm are demonstrated for the solid-type and hollow-type Cu2–xTe nanocrystals, respectively. The experimentally observed extinction spectra and calculated extinction spectra based on the electrostatic approximation are studied. The LSPR responses in the near-infrared (NIR) region for both solid and hollow Cu2–xTe nanocrystals are affected by the refractive index of the medium, whereas the NIR resonance shift is more obvious in the hollow-type Cu2–xTe nanocrystals. Furthermore, the localized surface plasmon band of the Cu2–xTe nanostructures can be tuned by post processing via oxidation ...

We reported a 65 inches amorphous oxide thin film transistors active-matrix organic light-emitting diode television panel. The thin film transistor shows an excellent characteristic. The long range threshold voltage uniformity is 0.34V. The side by side organic light-emitting diode device is realized by fine metal mask. The dam and fill encapsulation method shows a simple process procedure and high stability.

This paper investigates degradation behavior induced by the self-heating effect for InGaZnO (IGZO) thin-film transistors (TFTs). Both the surrounding oxide and other thermal insulating materials, as well as the low thermal conductivity of the InGaZnO layer itself, cause the self-heating effect in InGaZnO TFTs. The heated channel layer enhances the threshold voltage shift, and the evolution of threshold voltage shift is found to be dominated by charge-trapping effects. Moreover, a nonuniform distribution of channel carrier concentration leads to an uneven temperature distribution throughout the IGZO active layer, which results in the asymmetrical degradation behavior after the self-heating operation. Further verifications indicate that the degree of the threshold voltage shift is only dependent on stress power, regardless of stress Vg, Vd, and channel length. Further, two-stage dependence of the threshold voltage shift on dynamic stress frequency is found.

We have successfully fabricated large sized amorphous indium–gallium–zinc-oxide based active-matrix liquid-crystal displays, which uses Molybdenum/Aluminum/Titanium as source/drain electrode. In this study, an oxygen-rich etch stop layer acts as the oxygen atom supplier and converts the titanium layer into titanium oxide layer, which is found to induce instability of the device. Sample without titanium oxide has an initial threshold voltage shift is less than ±0.1 V after the repeatedly measuring over a period of two weeks. In addition, the IGZO based device demonstrated superior transfer characteristic. This paper established that the stability of the amorphous indium–gallium–zinc-oxide based active-matrix liquid-crystal display can be predicted by Stretched-Exponential model.

ThispaperinvestigatestheeffectofDCandACbias-stressinduceddegradationbehaviorinamorphousInGaZnOthin-filmtransistors (TFTs)underlightillumination.Draincurrent-gatevoltage(ID-VG)aswellascapacitance-voltage(C-V)measurementsareemployed to analyze the degradation mechanism. Illuminated DC stress leads to not only a negative parallel shift but also a C-V curve distortion at the off-state. This can be attributed to barrier-lowering near the drain side due to the asymmetrical hole-trapping effect. To further verify the origin of the degradation behavior, AC bias with identical stress voltage is imposed on either the gate terminal or the drain terminal. It is deduced that the hole-trapping phenomenon near the drain side is dominated by the voltage across the gate and drain, and is responsible for the degradation characteristic after stress carried out under light illumination.

The plasma-process-induced damage (PPID) of low-temperature polycrystalline silicon (poly-Si) thin-film transistors (TFTs) during the etching of the poly-Si film was investigated in this paper. The results reveal the relationship between the device degradation and the PPID during TFT liquid-crystal-display fabrication. This degradation is caused in part by the damage at the edge of the poly-Si film in plasma exposure. The trapped-state densities Ntrap are measured to clarify the relationship between instability and plasma etching damages. The plasma-process condition substantially affects the PPID of the poly-Si etching process. The main mechanism is the generation of charge trapping states at the poly-Si grain boundary in the damaged edge of the TFT channel active region. The electrical recovery from the plasma damage is also studied with various postetching treatments. Hydrogen-base plasma treatment and laser anneal process are revealed to improve the device characteristics due to reduction of charge trapping states.

Tetragonal chalcopyrite CuIn-(S1−xSex)2 (0 ≤ x ≤ 1) nanocrystals were synthesized by reacting a mixture of CuCl, InCl3, S, and Se in the presence of oleylamine at 265 °C. The S/Se composition ratio in the CuIn(S1−xSex)2 could be tuned across the entire composition range of x from 0 to 1 by modulating the S/Se reactant mole ratio. The tetragonal lattice constants, that is, a and c, increase linearly with the increase of Se content, following Vegard’s law. The band gap energies of CuIn(S1−xSex)2 nanocrystals could be tuned in the range between 0.98 and 1.46 eV and change nonlinearly with respect to x, deriving a bowing parameter of 0.17 eV. In addition, the method developed in this study was scalable to achieve gram-scale production of stoichiometry-controlled CuIn(S1−xSex)2 and CuIn1−xGaxSe2 nanocrystals.

We present the light-on results of our 65-inch organic ***light-emitting diode (OLED) panel fabricated by the inkjet printing (IJP) process. The panel uses solution-processable OLED material for the hole injection layer (HIL), the hole transporting layer (HTL) and the emitting layers (EML) for the red, green and blue colors. It is found that fine-tuning the vacuum dry speed after the inkjet printing process can improve the uniformity of the pixels. The results show that we can successfully fabricate a 65-inch OLED panel with a high degree of pixel uniformity.

Organic light‐emitting devices (OLEDs) have shown superior characteristics and are expected to dominate the next‐generation flat‐panel displays. Active‐matrix organic light‐emitting diode (AMOLED) displays, however, have stringent demands on the performance of the backplane. In this paper, the development of thin‐film transistors (TFTs) based on indium gallium zinc oxide (IGZO) on both Gen 1 and 6 glasses, and their decent characteristics, which meet the AMOLED requirements, are shown. Further, several display prototypes (e.g., 2.4” AMOLED, 2.4” transparent AMOLED, and 32” AMLCD) using IGZO TFTs are demonstrated to confirm that they can indeed be strong candidates for the next‐generation TFT technology not only of AMOLED but also of AMLCD (active‐matrix liquid crystal display).

Advanced harmonic balance simulation capabilities have been used to investigate linearity behavior in RF power laterally diffused metal-oxide semiconductor (LDMOS) devices with different laterally graded channel doping profiles. Harmonic balance analysis provides relevant device information from device-level simulations and yields performance metrics of RF circuits. The linearity behavior of simple quasi-1-D structures with different graded channel doping profiles was investigated; the analysis was then extended to a more realistic power LDMOS device. The third-order intermodulation distortion product reveals the important role of lateral channel doping. The analysis lays groundwork for device optimization for improved linearity.

Device-level simulation capabilities have been developed to investigate low-frequency noise behavior in p-type Si0.7Ge0.3/Si heterostructure MOS (SiGe p-HMOS) transistors. The numerical model is based on the impedance field method; it accounts for a trap-induced carrier number fluctuation, a layer-dependent correlated mobility fluctuation, and a Hooge mobility fluctuation in the buried and parasitic surface channels, respectively. Simulations based on such models have been conducted for SiGe p-HMOS transistors, and the results have been carefully correlated with experimental data. Quantitative agreement has been obtained in terms of the noise level dependence on gate biases, drain currents, and body biases, revealing the important role of the dual channels in the low-frequency noise behavior of SiGe p-HMOS devices.

A fast two-point measurement methodology, applicable to nano-scale devices, is introduced to separate electron trapping (Not, e) from interface state contributions (Nit) in hot carrier (HC) induced ΔVt in n-type RMG SOI FinFETs. It is shown that Not, e component is comparable to or dominates over Nit for high-Vg (≥ Vd) hot carrier stress (HCS). The time power-law exponent for HC induced Not, e is larger than 0.2, indicating the observed Not, e is partly due to injection of hot carriers instead of purely parasitic PBTI effect caused by the cold carriers.

AMOLED displays based on metal oxide film as active channel layer are fabricated. To achieve cost-competitive process in OLED manufacturing, solution-processed HIL, HTL and pixilated EML (RGB) layers followed by evaporation process for other layers are demonstrated in this work. Meanwhile, the AMOLED backplanes possessing low power consumption and high frequency were fabricated on metal oxide TFTs with high mobility (23.13 cm2/Vs) technology. A 14” qHD AMOLED in 79 ppi-resolution was realized with IGZO based active matrix panel.

We demonstrated a defect free 32-inch large scaled amorphous indium-gallium-zinc-oxide based active-matrix organic light-emitting diode television panel. The panel achieves good image quality, such as high contrast ratio, a wide viewing angle, and fast response time, and the module thickness is only 3 mm. The thin film transistor shows excellent characteristic and the compensation pixel circuit is used. The side by side organic light-emitting diode device is realized by fine metal mask.

We reported large size amorphous Indium-Gallium-Zinc-Oxide and Indium-Tin-Zinc-Oxide thin film transistors active-matrix organic light-emitting diode television development history in AUO. The Gen6 threshold voltage uniformity can lower than 1.0V. Amorphous Indium-Tin-Zinc-Oxide thin film transistors show a higher mobility of 33.2 cm 2 /VS. Amorphous 56 inches back channel etch type Indium-Tin-Zinc-Oxide active-matrix organic light-emitting diode television is 1st time revealed. Metal-organic chemical vapor deposition system is used to evaluate the new high mobility material. The side-by-side organic light-emitting diode device is realized by fine metal mask. The dam and fill encapsulation method shows a simple process procedure and highly stability. Ink jet printing is adopted to produce a small size full color panel. By the application of compensation pixel circuit, the panel drove by AUO engine shows an excellent characteristic.

To further device scaling, a new hetero-channel MOS device is considered. A novel Ge/SiGe/Si lateral hetero-channel p- FET that can significantly reduce band-to-band tunnelling (BTBT) leakage, retain high current drivability, and good electrostatics is introduced in this paper. Through detailed BTBT model in PDE simulators the on-current and off current in p- FETs are analyzed. The simulation results show one-order of magnitude reduction (>20) in minimum off current and high drive current. Lateral hetero-channel p-FET provides a promising solution for future highly scaled CMOS technology. Index Terms — SiGe; field effect transistor; BTBT leakage; device scaling

In this paper, a wide tuning range switched current-reused VCO for 2.5 GHz and 3.4 GHz WiMAX applications is presented. The frequency bands consist of eight switched sub-bands and cover 2.438-2.971 GHz and 3.104-3.786 GHz. The measured phase noise at 100-kHz and 1-MHz offset frequencies are -101.47 and -119.28 dBc/Hz at lower band and -103.99 and 122.28 dBc/Hz at higher band. With 1.5V voltage supply, the power consumption of the VCO is 2.886 mW. This circuit was fabricated by TSMC 0.18 m CMOS process.

Electronic structures and band topology of a single Sb(111) bilayer in the buckled honeycomb configuration are investigated using first-principles calculations. A nontrivial topological insulating phase can be induced by tensile strain, indicating the possibility of realizing the quantum spin Hall state for Sb thin films on suitable substrates. The presence of buckling provides an advantage in controlling the band gap through an out-of-plane external electric field, making a topological phase transition with six spin-polarized Dirac cones at the critical point. With a tunable gap and reversible spin polarization, Sb thin films are promising candidates for spintronic applications.

This paper investigates the degradation mechanism under self-heating stress for InGaZnO thin film transistor. The apparent positive threshold voltage (Vt) shift and on-current degradation indicate that the combination of trap states generation and electron trapping effect occur during stress. Furthermore, the asymmetric degradation behavior in the Id-Vg saturation measurement demonstrates that the trap states location is near the source side since the relative vertical electrical field is higher than drain side. Moreover, the Joule heating generated by self-heating operation can enhance electron trapping effect and cause larger Vt shift in comparison with the gate-bias stress.

This letter investigates asymmetrical degradation behavior induced by the self-heating effect in InGaZnO thin-film transistors. Both the surrounding oxide and other thermal insulating material, as well as the low thermal conductivity of the InGaZnO layer itself, cause the self-heating effect in InGaZnO thin-film transistors. The heated channel layer enhances threshold voltage shift, and the evolution of threshold voltage shift is found to be dominated by charge-trapping effect. Moreover, a non-uniform distribution of channel carrier concentration leads to an uneven temperature distribution through the InGaZnO active layer and results in the asymmetrical degradation behavior after self-heating operation.

We report, for the first time, colloidal synthesis of quinary CuIn1−xGax(SySe1−y)2 (CIGSSe) nanocrystals across the entire composition range (x,y) = 0 to 1 with band gaps tunable in the range of 0.98 to 2.40 eV by facile chemical synthesis. As a proof-of-concept, thin-film solar cells made by using the CIGSSe nanocrystal inks as an absorber layer precursor exhibited an efficiency over 1% under AM 1.5 illumination.