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In this study, the electrical characteristics and hot-carrier reliability are investigated in via-contact type amorphous indium–gallium–zinc oxide thin-film transistors (TFTs) with different field-plate structures, generally used as a light-shielding layer. Compared to a conventional symmetric structure, the output current characteristics of the asymmetric structures with a source-connected (drain-connected) field plate are more saturated (unsaturated). The source-connected field plate (SCFP) structure exhibits a good channel control ability, which can effectively suppress the drain-induced barrier-lowering effect and improve the IR-drop phenomena to achieve uniform brightness in each pixel over a large-area display. In addition, this structure demonstrates a good hot-carrier stress (HCS) stability confirmed by simulations and energy bands analysis. Based on the results of this study, it is proposed that the SCFP structure with stably saturated output current characteristics and HCS reliability is suitable for driving TFTs in active-matrix organic light-emitting diode (AM-OLED) applications.

In this work, the supercritical oxygen treatment is proposed to passivate the defects of enhancement-mode p-GaN high-electron mobility transistors. After the treatment, the treated device gets enhanced in ON-state current and transconductance without changing the threshold voltage. Thus, the supercritical oxygen may not affect Mg doping concentration of the p-GaN layer, degrading the p-GaN layer after the treatment. The statistical analysis indicates uniformity of devices is improved after the treatment. The gate lag and pulsed $\text{I}_{\text {D}}$ - $\text{V}_{\text {D}}$ measurements are proposed to examine the interface between the passivation layer and the AlGaN layer. The few trapped electrons in defects exhibit the suppression of the charge trapping effect. Based on these results mentioned above, the physical model is proposed to explain the phenomenon. The pristine passivation layer has a number of dangling bonds which capture the electrons and lead to the charge trapping effect. The supercritical oxygen permeates into material matrix, repairing the dangling bonds. Therefore, the technique exhibits potential for power device improvement, enabling effective practical application in the future.

In this letter, a light recovery method is proposed to analyze defect concentration and energy level distribution by changing the wavelength. The AlGaN/GaN high electron mobility transistors (HEMTs) under hot carrier stress (HCS) conditions will experience a severe electrical degradation. The threshold voltage ( ${V}_{\textit {th}}$ ) shifts to the right, and the on current and the off current both decrease. TCAD simulations of the electric field distribution and energy bands are performed to examine the degradation behaviors under HCS on the GaN-based HEMTs. The degradation of electrical characteristics can be effectively recovered by using the illumination method in AlGaN/GaN HEMTs. In addition, the light wavelength of illumination is positively correlated with the recovery effect, which is expected to provide effective measurements and analyses for AlGaN/GaN HEMT devices, which is expected to clarify the defect energy level distribution of HEMT device degradation.

This work proposes forming-free HfO2-based resistance random access memory (RRAM) using X-ray irradiation which overcomes the bottleneck of the conventional forming process, that of the need for a larger forming voltage with scaling. In addition, a large irradiation area is beneficial to the mass production of memory devices. This forming-free device has a better memory window compared to the device without X-ray irradiation. Moreover, the forming-free device has good reliability as the device without X-ray irradiation. To analyze the physical mechanism, the conduction mechanism was investigated by the current-fitting technique, and irradiation experiments with varying X-ray energies and times were performed. Finally, a physical model is proposed to explain the mechanism of the forming-free RRAM from X-ray irradiation.

Transactional Synchronization Extensions (TSX) have been introduced for hardware transactional memory since the 4th generation Intel Core processors. TSX provides two software programming interfaces: Hardware Lock Elision (HLE) and Restricted Transactional Memory (RTM). HLE is easy to use and maintains backward compatibility with processors without TSX support, while RTM is more flexible and scalable. Previous researches have shown that critical sections protected by RTM with a well-designed retry mechanism as its fallback code path can often achieve better performance than HLE. More parallel programs may be programmed in HLE, however, using RTM may obtain greater performance. To embrace both productivity and high performance of parallel programs with TSX, we present a framework built on QEMU that can dynamically transform HLE instructions in an application binary to fragments of RTM codes with adaptive tuning on the fly. Compared to HLE execution, our prototype achieves 1.56 x speedup with 8 threads on average. Due to the scalability of RTM, the speedup will be more significant as the number of threads increases.

This work investigates the influence of a supercritical fluid (SCF) treatment on the characteristics of resistive random access memory. A comparison between the experimental results for the device at initial, after the overset process, and after the SCF treatment, shows that the treatment dopes oxygen ions and generates defects in the switching region (SR). Moreover, the changes in the ratio of the components of the SR after the SCF treatment improve memory characteristics, including a lower set/reset voltage (VSET/VRESET), and higher resistances at low resistance state and high resistance state.

The objective of this study was to assess the relationship between the scores collected from Borg's rating of perceived exertion (RPE) scale and the heart rates (HR) of young Taiwanese men. Three exercises types (dynamic, partially dynamic, and static) were performed by 12 participants (six were familiar with Borg's scale and 6 were unfamiliar) under nine test conditions of three load levels for each exercise. The effect of familiarity on the relationship between RPE and HR was also examined. The results showed that the familiarity of the participants regarding the Borg's scale did not affect the scores. The relationship between Borg's RPE 6–20 scale and the HR values during dynamic exercise was described by the regression equation HR = 8.88 × RPE + 38.2 (beats/min). The HR had lower correlations with RPE values when the participants performed both partially dynamic and static exercises. The findings may serve as a reference when using Borg's RPE scale to evaluate the physical exertion of young Taiwanese men.

This work investigates the effect of X-ray accelerating voltage (Vacc) on the structural repair of HfZrOx ferroelectric random-access memory. We found that X-rays are able to break the molecular bonds due to missing electrons, thereby repairing the material structure. To further understand the influence of X-ray Vaccon structural repair, we conducted different Vaccconditions, with results showing that there is only a small improvement under high Vacc. However, the improvement is much clearer under low Vacc. To illuminate these results, we propose a physical model which is based on different X-ray energies that will have different energy penetration capacities.

Objective: This study investigated the change in new diastolic indexes in patients with uremia who undergo regular hemodialysis (H/D). Methods: We studied 81 patients with uremia (41 men and 40 women) receiving regular H/D. All patients were in sinus rhythm before H/D. They had normal left ventricular systolic performance without regional wall-motion abnormality. Three patients were excluded because of atrial fibrillation after H/D. Patients were separated by the amount of body fluid removed during H/D procedure: 30 patients with H/D amount less than 2 kg (group 1), 33 patients with H/D amount between 2 and 3 kg (group 2), and 18 patients with H/D amount larger than 3 kg (group 3). They received complete transthoracic echocardiographic examinations. Flow propagation velocity (FPV) was measured by color M-mode echocardiography in apical 4-chamber view. Mitral annulus Doppler tissue velocities (peak systolic [Sa], early diastolic [Ea], and late diastolic [Aa]) were measured from septal, lateral, inferior, and posterior walls. All these parameters were obtained immediately before and after H/D. Paired data were compared. Results: In patients with removed fluid amount less than 2 kg (group 1), the change of all diastolic parameters showed insignificant change except FPV (peak mitral E, P = .14; peak mitral A, P = .916; FPV, P = .009; septal Sa, P = .173; septal Ea, P = .295; septal Aa, P = .649). In patients with H/D amount between 2 and 3 kg, the change of all diastolic parameters showed statistically significant difference except Sa (peak mitral E, P = .001; peak mitral A, P = .001; FPV, P = .001; Sa, P = .589; Ea, P = .001; Aa, P = .015). In patients with H/D amount larger than 3 kg, Sa still showed insignificant change. Ea, Aa, and FPV showed significant difference after H/D (peak mitral E, P = .001; peak mitral A, P = .035; FPV, P = .008; septal Sa, P = .777; septal Ea, P = .014; septal Aa, P = .048). Conclusion: In patients with normal left ventricular systolic function, FPV was preload dependent. Diastolic phase mitral annulus Doppler tissue velocities (Ea and Aa) behaved differently according to the amount removed during H/D. They were preload independent when the amount removed during H/D was less than 2 kg. When the amount removed during H/D was larger than 2 kg, diastolic phase mitral annulus Doppler tissue velocities changed significantly. That is to say, diastolic phase mitral annulus Doppler tissue velocities were not totally preload independent. For systolic phase mitral annulus Doppler tissue velocity index (Sa), it was preload independent.

Objectives: The aim of this study was to investigate the changes of flow propagation velocity (FPV) after regular hemodialysis (H/D) in patient who were uremic with different baseline left ventricular (LV) functions. Methods: In all, 24 patients with uremia and abnormal LV systolic function were enrolled in this study and 30 patients with uremia and normal LV systolic performance served as the control group. All patients had in sinus rhythm and underwent a comprehensive transthoracic echocardiographic examination and mitral FPV by color M-mode echocardiography before and after H/D. Results: The decline in FPV before H/D was proportional to the decline in the baseline LV function, whereas FPV after H/D varied according to the LV ejection fraction. An obvious decrement of FPV for patients with normal LV systolic function was noted, but no obvious difference was seen for patients with abnormal LV systolic function. Conclusion: FPV was strongly preload dependent for patients with normal LV systolic function. It was not significantly influenced by preload for patients with abnormal LV systolic function. FPV is a relatively good diastolic parameter for investigating patients with LV systolic dysfunction.

In this work, capacitance-voltage (C-V) measurement and analysis were performed on silicon (Si)-based devices at low temperature (77 K). By this method, the C-Vcurves were compared for two devices with channel materials of Si and silicon-germanium (SiGe). The lattice mismatch of SiGe results in more defects at the interface between the channel and the gate insulator layer, which cause abnormal C-Vproperties. Through comprehensive theoretical calculation, proved by Silvaco simulation, an energy band diagram and physical model are proposed. Furthermore, the distribution of donor-like states can be examined, which can assist in monitoring the interface quality.

Titration of evidence-based medications, important for treating heart failure (HF), is often underdosed by symptom-guided treatment. The aim of this study was to investigate, using echocardiographic parameters, stroke volume and left ventricular (LV) filling pressure to guide up-titration of medications, increasing prognostic benefits.

The forming process is a necessary and irreversible process to activate the resistance switching behavior in a resistance random access memory (RRAM) device. However, during the forming process, an overshoot current leads to device damage and causes inferior resistance switching characteristics; consequently, the process is considered to be a key factor in device degradation. In this paper, we find that a discontinuous conduction path can be formed by a pulse forming process such that the operation current can be reduced. We further investigate how the charge quantity during the forming process affects the carrier conduction mechanism of HRS, with all experiments and results demonstrated on one-transistor-one-resistor (1T1R) devices.