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The self-consistent technique for extracting density of states [DOS: g(E)] in an amorphous indium gallium zinc oxide (a-IGZO) thin film transistor is proposed and demonstrated. The key parameters are the g(E) of the a-IGZO active layer and the intrinsic channel mobility (μch). While the energy level (E) is scanned by the photon energy and gate-to-source voltage (VGS) sweep, its density is extracted from an optical response of capacitance-voltage characteristics. Using the Vos-dependent μch as another boundary condition, a linearly mapped DOS assuming a linear relation between VGS and E is translated into a final DOS by fully considering a nonlinear relation between VGS and E. The final DOS is finally extracted and verified by finding the self-consistent solution satisfying both the linearly mapped DOS and the measured VGS dependence of μch with the numerical iteration of a DOS-based μch model. The extracted final DOS parameters are NTA = 1.73 x 1017 cm-3 eV-1, NDA = 3.5 x 1015 cm-3 eV-1, kTTA = 0.023 eV, kTDGA = 1.2 eV, and EO = 1.7 eV with the formula of exponential tail states and Gaussian deep states. [ABSTRACT FROM AUTHOR]

A technique for extracting the acceptorlike density of states (DOS) of n-channel amorphous GaInZnO (a-GIZO) thin-film transistors based on the combination of subbandgap op- tical charge pumping and C-V characteristics is proposed. While the energy level is scanned by the photon energy and the gate voltage sweep, its density is extracted from the optical response of C-V characteristics. The extracted DOS shows the superpo- sition of the exponential tail states and the Gaussian deep states (NTA = 2 x 1018 eV' . cm3, NDA = 4 x iO'5 eV' . cm3, kTTA = 0.085 eV, kTDA = 0.5 eV, E0 = 1 eV). The TCAD simulation results incorporated by the extracted DOS show good agreements with the measured transfer and output characteris- tics of a-GIZO thin-film transistors with a single set of process- controlled parameters. [ABSTRACT FROM AUTHOR]

Abstract  We prove that if a simplicial complex Δ is shellable, then the intersection lattice L Δ for the corresponding diagonal arrangement is homotopy equivalent to a wedge of spheres. Furthermore, we describe precisely the spheres in the wedge, based on the data of shelling. Also, we give some examples of diagonal arrangements  where the complement is K(π,1), coming from rank-3 matroids. [ABSTRACT FROM AUTHOR]

Amorphous Gallium-Indium-Zinc-Oxide (GIZO) thin film transistors with short channels of 50 nm were successfully fabricated by e-beam lithographic patterning. The GIZO thin film transistors showed a high mobility of 8.2 cm2/V · s with on-to-off current ratios up to 108. Excellent short channel characteristics were also obtained with a small shift of the threshold voltages and no degradation of subthreshold slopes as VDS increased, even with short channel lengths of less than 100 nm. These promising results indicate that the GIZO thin film transistors could be a candidate for selection transistors in 3-D cross point stacking memory. [ABSTRACT FROM AUTHOR]

The major problem of fault diagnosis with a fault dictionary is the enormous amount of data. The technique used to manage this data can have a significant effect on the outcome of the fault diagnosis procedure. If information is removed from a fault dictionary in order to reduce the size of the dictionary, its ability to diagnose stuck-at faults and unmodeled faults may be severely debased. Therefore, we focus on methods for producing a dictionary that is both small and lossless-compacted. [ABSTRACT FROM AUTHOR]

An MPEG-4 audio-visual scene is composed of various types of media data represented as individual objects. It includes a scene description that refers to the spatio-temporal specification and behavior of individual objects. In this paper, we propose an MPEG-4 contents authoring system for generating MPEG-4 audio-visual scenes, by providing the visual environment for building the spatio-temporal scenario of media objects comprising the scene. The system, called MPEG-4 STUDIO, provides a comprehensive set of facilitative editing tools for composing MPEG-4 scenes, as well as tools for the automatic generation of creative MPEG-4 contents. The system's authoring environment and the process of generating MPEG-4 contents are presented in detail. [ABSTRACT FROM AUTHOR]

Multimedia contents can be provided to various environments such as home networking, video conferencing, tele-education, etc. These service environments are equipped with different end devices. MPEG-4 is the international standard for audio-visual presentation. Thus, it can be effectively applied to the multimedia contents service domain. This paper suggests a novel adaptive scheme that is capable of bridging the gap between the sender and receiver when MPEG-4 contents are transmitted In particular, an adaptive algorithm is proposed in streaming proper MPEG-4 waves to a specific type of terminals with different presentation capabilities such as data processing rate and throughput of network conditions. [ABSTRACT FROM AUTHOR]

Electrical bias and light stressing followed by natural recovery of amorphous hafnium-indium-zinc-oxide (HIZO) thin film transistors with a silicon oxide/nitride dielectric stack reveals defect density changes, charge trapping and persistent photoconductivity (PPC). In the absence of light, the polarity of bias stress controls the magnitude and direction of the threshold voltage shift (ΔVT), while under light stress, VT consistently shifts negatively. In all cases, there was no significant change in field-effect mobility. Light stress gives rise to a PPC with wavelength-dependent recovery on time scale of days. We observe that the PPC becomes more pronounced at shorter wavelengths. [ABSTRACT FROM AUTHOR]

We developed amorphous hafnium-indium-zinc oxide (HIZO) thin films as oxide semiconductors and investigated the films electrically and physically. Adding of hafnium (Hf) element can suppress growing the columnar structure and drastically decrease the carrier concentration and hall mobility in HIZO films. The thin film transistors (TFTs) with amorphous HIZO active channel exhibit good electrical properties with field effect mobility of around 10 cm2/Vs, S of 0.23 V/decade, and high Ion/off ratio of over 108, enough to operate the next electronic devices. In particular, under bias-temperature stress test, the HIZO TFTs with 0.3 mol % (Hf content) showed only 0.46 V shift in threshold voltage, compared with 3.25 V shift in HIZO TFT (0.1 mol %). The Hf ions may play a key role to improve the instability of TFTs due to high oxygen bonding ability. Therefore, the amorphous HIZO semiconductor will be a prominent candidate as an operation device for large area electronic applications. [ABSTRACT FROM AUTHOR]

The density of states (DOS)-based DC I-V model of an amorphous gallium-indium-zinc oxide (a-GIZO) thinfilm transistor (TFT) is proposed and demonstrated with selfconsistent methodologies for extracting parameters. By combining the optical charge-pumping technique and the nonlinear relation between the surface potential (4g) and gate voltage (VGS), it is verified that the proposed DC model reproduces well both the measured VGS-dependent mobility and the IDS-VGS characteristics. Finally, the extracted DOS parameters are NTA = 4.4 x 1017 cm-3 ∙ eV-1, NDA = 3 x 1015 cm-3∙eV-1, kTTA = 0.023 eV, kTDGA = 1.5 eV, and Eo = 1.8 eV, with the formulas of exponential tail states and Gaussian deep states. [ABSTRACT FROM AUTHOR]

Bipolar ac stress-induced instability of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors is comparatively investigated with that under a positive dc gate bias stress. While the positive dc gate bias stress-induced threshold voltage shift (ΔVT) is caused by the charge trapping into the interface/gate dielectric as reported in previous works, the dominant mechanism of the ac stress-induced ΔVT is observed to be due to the increase in the acceptorlike deep states of the density of states (DOS) in the a-IGZO active layer. Furthermore, it is found that the variation of deep states in the DOS makes a parallel shift in the IDS-VGS curve with an insignificant change in the subthreshold slope, as well as the deformation of the CG-VG curves. [ABSTRACT FROM AUTHOR]

Abstract-The source/drain region of amorphous GaInZnO thin-film transistor with self-aligned top-gate structure was defined by simple NH[sub3] plasma treatment instead of complicated processes, such as ion implantation and activation. When the source/drain region of active layer was exposed to NH[sub3] gas plasma, the series resistance of the transistor decreased considerably. It exhibited electrical properties, such as a field-effect mobility of 6 cm[sup2]/V s, a threshold voltage of 0.21 V, and a subthreshold swing of 0.23 V/dec. [ABSTRACT FROM AUTHOR]

We investigated the effect of the high-k TiOx (k∼40) gate dielectric on the mobility (μFE) of indium-gallium-zinc oxide (IGZO) transistors. As the thickness of the TiOx layer at the interface of the IGZO channel and SiNx gate dielectric layer increased from 2 to 8 nm, the μFE value was monotonously reduced from 9.9 to 1.8 cm2/V s. The degradation of the mobility was attributed to the Coulomb scattering mechanism rather than the phonon scattering mechanism of the high-k TiOx layer based on the behavior of the temperature-dependent mobilities for all of the IGZO transistors. [ABSTRACT FROM AUTHOR]

A fully transparent nonvolatile memory with the conventional sandwich gate insulator structure was demonstrated. Wide band gap amorphous GaInZnO (a-GIZO) thin films were employed as both the charge trap layer and the transistor channel layer. An excellent program window of 3.5 V with a stressing time of 100 ms was achieved through the well-known Fowler–Nordheim tunneling method. Due to the similar energy levels extracted from the experimental data, the asymmetrical program/erase characteristics are believed to be the result of the strong trapping of the injected negative charges in the shallow donor levels of the GIZO film. [ABSTRACT FROM AUTHOR]

Amorphous-gallium-indium-zinc-oxide (a-GIZO) thin filmtransistors (TFTs) are fabricated without annealing, using processes and equipment for conventional a-Si:H TFTs. It has been very difficult to obtain sound TFT characteristics, because the a-GIZO active layer becomes conductive after dry etching the Mo source/drain electrode and depositing the a-SiO2 passivation layer. To prevent such damages, N2O plasma is applied to the back surface of the a-GIZO channel layer before a-SiO2 deposition. N2O plasma-treated a-GIZO TFTs exhibit excellent electrical properties: a field effect mobility of 37 cm2/V s, a threshold voltage of 0.1 V, a subthreshold swing of 0.25 V/decade, and an Ion/off ratio of 7. [ABSTRACT FROM AUTHOR]

We have demonstrated a self-aligned top-gate amorphous gallium indium zinc oxide thin film transistor (a-GIZO TFT). It had a field effect mobility of 5 cm2/V s, a threshold voltage of 0.2 V, and a subthreshold swing of 0.2 V/decade. Ar plasma was treated on the source/drain region of the a-GIZO active layer to reduce the series resistance. After Ar plasma treatment, the surface of the source/drain region was divided into In-rich and In-deficient regions. The a-GIZO TFT also had a constant sheet resistance of 1 kΩ/□ for a film thickness of over 40 nm. The interface between the source/drain Mo metal and the Ar plasma-treated a-GIZO indicated a good Ohmic contact and a contact resistivity of 50 μΩ cm2. [ABSTRACT FROM AUTHOR]

In this letter, we investigated the effects of source/drain series resistance on amorphous gallium-indium-doped zinc-oxide (a-GIZO) thin film transistors (TFTs). A linear least square fit of a plot of the reciprocal of channel resistance versus gate voltage yields a threshold voltage of 3.5 V and a field-effect mobility of about 13.5 cm² / V · s. Furthermore, in a-GIZO TFTs, most of the current flows in the distance range of 0-0.5 µm from the channel edge and shorter than that in a-Si:H TFTs. Moreover, unlike a-Si:H TFTs, a-GIZO TFTs did not show an intersection point, because they did not contain a highly doped ohmic (n+) layer below the source/drain electrodes. [ABSTRACT FROM AUTHOR]

The grain size effect on the dielectric, ferroelectric, and piezoelectric properties of BaTiO3 (BT) ceramics with different Ba/Ti ratios, prepared by solid-state reaction and conventional sintering, was investigated, and the corresponding electrical properties of these ceramics with similar grain size were compared. The BT ceramics with Ba/Ti ratios of 0.997, 1.000, and 1.003 and grain sizes of approximately 1 μm exhibited dielectric constants of 4265, 4275, and 4835 and converse piezoelectric coefficients, d33*, of 703, 645, and 466 pm V−1, respectively. The remanent polarization, Pr, was relatively higher for Ba-excess BT ceramics. These results indicated that, in Ti-excess BT ceramics, domain walls were strongly pinned due to oxygen vacancies under small electric fields and they were de-pinned at high electric fields, contributing to the higher d33*, while the orientation of domains in high electric fields did not retain upon electric field unloading, resulting in lower Pr. [ABSTRACT FROM AUTHOR]

The role of thermal annealing treatment in the enhancement of the piezoelectric and ferroelectric properties of 0.3BaTiO3–0.1Bi(Mg1/2Ti1/2)O3–0.6BiFeO3 (0.3BT–0.1BMT–0.6BF) lead-free piezoelectric ceramics was investigated. Mechanical stress induced by ceramic processing such as polishing and cutting could severely affect the electrical properties of 0.3BT–0.1BMT–0.6BF lead-free piezoelectric ceramics. In order to explore the impact of mechanical processing on their electrical properties, polished and cut samples were thermally annealed to remove damaged surface layers. It was found that the remanent polarization (Pr; 27.27 μC cm−2) and large-field piezoelectric coefficient (d33*; 334 pm V−1) for the thermally annealed sample were remarkably enhanced in comparison to those of the polished sample (Pr of 17.57 μC cm−2 and d33* of 271 pm V−1). This significant enhancement of piezoelectric and ferroelectric properties in thermally annealed ceramics, without any considerable change in grain size, suggests a major contribution of thermal annealing to the removal of damaged surface layers. [ABSTRACT FROM AUTHOR]

Analog in-memory computing synaptic devices are widely studied for efficient implementation of deep learning. However, synaptic devices based on resistive memory have difficulties implementing on-chip training due to the lack of means to control the amount of resistance change and large device variations. To overcome these shortcomings, silicon complementary metal-oxide semiconductor (Si-CMOS) and capacitor-based charge storage synapses are proposed, but it is difficult to obtain sufficient retention time due to Si-CMOS leakage currents, resulting in a deterioration of training accuracy. Here, a novel 6T1C synaptic device using only n-type indium gaIlium zinc oxide thin film transistor (IGZO TFT) with low leakage current and a capacitor is proposed, allowing not only linear and symmetric weight update but also sufficient retention time and parallel on-chip training operations. In addition, an efficient and realistic training algorithm to compensate for any remaining device non-idealities such as drifting references and long-term retention loss is proposed, demonstrating the importance of device-algorithm co-optimization. [ABSTRACT FROM AUTHOR]

Purpose: To investigate orthopaedic patient compliance with patient-reported outcome measures (PROMs) and identify factors that improve response rates. Methods: Our search strategy comprised a combination of key words and database-specific subject headings for the concepts of orthopaedic surgical procedures, compliance, and PROMs from several research databases from inception to October 11, 2022. Duplicates were removed. A total of 97 studies were included. A table was created for the remaining articles to be appraised and analyzed. The collected data included study characteristics, follow-up/compliance rate, factors that increase/decrease compliance, and type of PROM. Follow-up/compliance rate was determined to be any reported response rate. The range and average used for analysis was based on the highest or lowest number reported in the specific article. Results: The range of compliance reported was 11.3% to 100%. The overall response rate was 68.6%. The average baseline (preoperative/previsit) response rate was 76.6%. Most studies (77%) had greater than 50% compliance. Intervention/reminder of any type (most commonly phone call or mail) resulted in improved compliance from 44.6% to 70.6%. Young and elderly non-White male patients had the lowest compliance rate. When directly compared, phone call (71.5%) resulted in a greater compliance rate than electronic-based (53.2%) or paper-based (57.6%) surveys. Conclusions: The response rates for PROMs vary across the orthopaedic literature. Patient-specific factors, such as age (young or old) and race (non-White), may contribute to poor PROM response rate. Reminders and interventions significantly improve PROM response rates. Clinical Relevance: PROMs are important tools in many aspects of medicine. The data generated from these tools not only provide information about individual patient outcomes but also make hypothesis-driven comparisons possible. Understanding the factors that affect patient compliance with PROMs is vital to our accurate understanding of patient outcomes and the overall advancement of medical care.

Purpose: Magnetic resonance imaging (MRI)-directed stereotactic body radiation therapy (SBRT) has been established as a safe and effective treatment for prostate cancer. For patients with contraindications to MRI, CT-urethrogram is an alternative imaging approach to identify the location of the prostatic apex to guide treatment. This study sought to evaluate the safety of urethrogram-directed SBRT for prostate cancer.Methods: Between February 2009 and January 2014, 31 men with clinically localized prostate cancer were treated definitively with urethrogram-directed SBRT with or without supplemental intensity modulated radiation therapy (IMRT) at Georgetown University Hospital. SBRT was delivered either as a primary treatment of 35-36.25 Gray (Gy) in 5 fractions or as a boost of 19.5 Gy in 3 fractions followed by supplemental conventionally fractionated intensity modulated radiation therapy (45-50.4 Gy). Toxicities were recorded and scored using the Common Terminology Criteria for Adverse Events version 4.0 (CTCAE v.4.0).Results: The median patient age was 70 years with a median prostate volume of 38 cc. The median follow-up was 3.7 years. The patients were elderly (Median age = 70), and comorbidities were common (Carlson Comorbidity Index > 2 in 36%). 71% of patients utilized alpha agonists prior to treatment, and 9.7% had prior procedures for benign prostatic hyperplasia (BPH). The 3-year actuarial incidence rates of > Grade 3 GU toxicity and > Grade 2 GI toxicity were 3.2% and 9.7%, respectively. There were no Grade 4 or 5 toxicities.Conclusions: MRI is the preferred imaging modality to guide prostate SBRT treatment. However, urethrogram-directed SBRT is a safe alternative for the treatment of patients with prostate cancer who are unable to undergo MRI.