Various array types of 1‐diode and 1‐resistor stacked crossbar array (1D1R CA) devices composed of a Schottky diode (SD) (Pt/TiO2/Ti/Pt) and a resistive switching (RS) memory cell (Pt/TiO2/Pt) are ...fabricated and their performances are investigated. The unit cell of the 1D1R CA device shows high RS resistance ratio (≈103 at 1.5 V) between low and high resistance state (LRS and HRS), and high rectification ratio (≈105) between LRS and reverse‐state SD. It also shows a short RS time of <50 ns for SET (resistance transition from HRS to LRS), and ≈600 ns for RESET (resistance transition from LRS to HRS), as well as stable RS endurance and data retention characteristics. It is experimentally confirmed that the selected unit cell in HRS (logically the “off” state) is stably readable when it is surrounded by unselected LRS (logically the “on” state) cells, in an array of up to 32 × 32 cells. The SD, as a highly non‐linear resistor, appropriately controls the conducting path formation during the switching and protects the memory element from the noise during retention.
1 diode 1 resistor (1D1R) resistive memory devices with the crossbar array configuration composed of a stacked Schottky diode (Pt/TiO2/Ti/Pt) and unipolar resistive (URS) memory (Pt/TiO2/Pt) elements are fabricated, and their fluent functionality is proven. Atomic force microscopy is used to image one memory cell and scanning electron microscopy is used to study the 32 × 32 memory array.
Dynamic random-access memory (DRAM) devices are essential volatile memory components in most digital devices. With the increasing demand for further low-power and high-density devices, the planar ...structure of DRAM devices encountered a “memory wall”, ushering in an era of 3D DRAM architecture. InGaZnO-based thin-film transistors (IGZO TFTs) have a very low off current (<10–22 A/μm), representing a solution for new channel materials for next-generation 3D DRAM devices. IGZO TFTs are back-end-of-line (BEOL)-compatible, enabling them to move the DRAM peripheral circuitry under the memory array and integrate stacked DRAM cells. IGZO thin films have been widely studied for next-generation flat panel display applications. However, most studies have employed sputtering and solution-based systems, which hinder process compatibility in 3D DRAM devices with complex structures. Atomic layer deposition (ALD) is a viable alternative for solving these challenges. In this paper, we comprehensively review the reported Zn-, In-, Sn-, and Ga-based oxide semiconductors in terms of the ALD process (precursors, reactants, growth temperature, etc.), together with material properties such as purity, crystallinity, and electrical properties.
Highly ordered crystalline InGaZnO (c-IGZO) TFTs have been demonstrated in subsequent processes above 550 °C compatible with memory applications. Notably, c-IGZO featured strong immunity to high ...temperature and hydrogen-containing processes unlike amorphous IGZO (a-IGZO) where agglomeration occurs. The c-IGZO TFTs with optimized process in this study show a higher on-current (\mathrm{I}_{\mathrm{o}\mathrm{n}}) at a similar \mathrm{V}_{\mathrm{t}\mathrm{h}} of −1 V, and \mathrm{I}_{\mathrm{off}} of 1.82\times 10^{-18} A/\mum compared with a-IGZO TFTs. In addition, striking enhancement in the short channel margin and \mathrm{V}_{\mathrm{th}} stability over a-IGZO was achieved. With thin gate-oxide (50 Å), the improved device performance was realized such as S.S. \times 0.41, DIBL \times 0.18, and \mathrm{I}_{\mathrm{on}}× 76.5 compared with a-IGZO TFT at \mathrm{T}_{\mathrm{ox}} 100 Å.
Fully functional crossbar array ReRAM devices with 32 32 memory block size are reported by Cheol Seong Hwang and co-workers . The schematic structure of the 1 diode-1 resistor crossbar array devices ...is shown in the image. The adopted Schottky diode, serially connected with a unipolar resistive switching memory element, suppresses the sneak-current flow. It also controls the conducting path formation during switching and protects the memory from noise during retention.
Non-volatile memory-based analog computation-in-memory can improve energy efficiency and latency of artificial intelligence edge devices by minimizing the movement of data between processors and ...memories. Here, we developed reliable HfO 2 -based resistive synaptic cell (RSC) arrays with 16-level analog properties. We revealed that oxygen diffusion barriers not only suppress the negative-set phenomenon and but also improve retention properties. In addition, we fully integrated 256Kcell 1T1R cross-bar RSC arrays using a conventional CMOS process, and demonstrated their improved multiply-accumulate operations with ~94% accuracy.
Introduction
The purpose of this study was to compare the sagittal spinopelvic parameters between young normal asymptomatic adults and older normal asymptomatic adults without localized segmental ...disc degeneration.
Materials and methods
Standing sagittal radiographs of the whole spine including the pelvis in 342 adult male volunteers (Group 1:
n
= 184, average age 21.2 years, range 19–28 vs. Group 2:
n
= 158, average age 63.8 years, range 53–79) were analyzed prospectively. Volunteers with history of spine operation, spinal disease, chronic pain in their back or legs, scoliosis, spondylolisthesis, 1–3 segmental disc space narrowing, and/or compression fractures in radiographs were excluded. The following parameters were included: thoracic kyphosis between T5 upper endplate (UEP) and T12 lower endplate (LEP), thoracolumbar kyphosis (T10 UEP − L2 LEP), T12 LEP-horizontal (H) angle (minus denotes EP above the H line), lumbar lordosis (T12 LEP − S1 UEP), lower lumbar lordosis (L4 UEP − S1 UEP), sacral slope, pelvic incidence and distances from C7 plumb/T12 plumb to the postero-superior endplate of S1. Group 2 (old men group) demonstrated larger thoracic kyphosis (30.1° ± 8.6° vs. 21.1° ± 7.8° in Group 1,
P
< 0.001), thoracolumbar kyphosis (10.0° ± 7.5° vs. 2.8° ± 7.1° in Group 1,
P
< 0.001), total lumbar lordosis at T12–S1 (57.3° ± 8.8° vs. 52.2° ± 9.2° in Group 1,
P
< 0.001), lower lumbar lordosis at L4–S1 (39.4° ± 6.7° vs. 32.4° ± 6.4° in Group 1,
P
< 0.001), a higher ratio of lower to total lumbar lordosis (69.5 ± 11.6 vs. 62.7 ± 10.6 % in Group 1,
P
< 0.001) and T12 LEP-H angle (−20.4° ± 5.7° vs. −15.7° ± 5.1° in Group 1,
P
< 0.001). There were no significant differences in sacral slope (36.5° ± 7.3° in Group 1 vs. 36.8° ± 6.7° in Group 2,
P
= 0.67) and pelvic incidence (46.5° ± 7.7° in Group 1 vs. 48.2° ± 8.5° in Group 2,
P
= 0.06). There was no significant difference in the measurement of distance from C7 plumb to the postero-superior endplate of S1 (−0.7 ± 2.4 cm in Group 1 vs. −0.3 ± 2.7 cm in Group 2,
P
= 0.197). However, the distance from T12 plumb to the postero-superior endplate of S1 (−0.7 ± 1.7 cm in Group 1 vs. −2.2 ± 1.7 cm in Group 2,
P
< 0.001) demonstrated a significant difference.
Conclusion
The old men group demonstrated a significant increase in thoracic kyphosis, thoracolumbar kyphosis, total and lower lumbar lordosis, a higher ratio of lower to total lumbar lordosis, and a longer distance from T12 plumb to the postero-superior endplate of S1 without changes in sacral slope and global sagittal balance.
Despite its high incidence rate, vertebral fragility fracture (VFF) is frequently underdiagnosed due to the absence of marked symptoms. This study evaluated the diagnostic accuracy of our suggested ...physical examinations and compared them with that of plain radiographs. Patients over 65 years of age with sudden back pain within the preceding 3 weeks were enrolled. Physical examinations in three different positions and a closed-fist percussion test were performed, and the presence of VFF was evaluated through confirmatory radiographic tools. We assessed the diagnostic accuracy of each physical examination and compared them with the interpretation of plain radiographs and examined the patient-reported pain locations based on the VFF level. A total of 179 patients were enrolled. The forward bending in supine (FB-SU) test demonstrated superior diagnostic values (sensitivity: 90.6%, specificity: 71.2%), which outperformed those of plain radiographs (sensitivity: 68.9%, specificity: 71.9%). The location of patient-reported pain was generally close to or lower than the index fracture level. FB-SU showed the highest diagnostic accuracy and was more valuable than plain radiographs in diagnosing acute VFF. FB-SU is a simple and affordable screening test. If positive, physicians should highly suspect VFF even when based on vague evidence of acute fracture provided by plain radiographs.
Purpose The beneficial effects of a combination therapy using Bifidobacterium longum and galactooligosaccharide (GOS) for the treatment of atopic dermatitis (AD) have not been elucidated. Methods ...Gene expressions of interleukin (IL)-4 and IL-13 from peripheral blood mononuclear cells and fecal abundance of B. longum from 12-month-old infants were evaluated. Human primary epidermal keratinocytes (HEKs) and hairless mice were treated with B. longum, GOS, B. longum-derived extracellular vesicles (BLEVs), dinitrochlorobenzene (DNCB), or a synbiotic mixture of B. longum and GOS. Expression of epidermal barrier proteins and cytokines as well as serum immunoglobulin E (IgE) levels were analyzed in HEKs and mice. Dermatitis scores, transepidermal water loss (TEWL), epidermal thickness, and fecal B. longum abundance were evaluated in mice. Results Fecal abundance of B. longum was negatively correlated with blood IL-13 expression in infants. B. longum or BLEVs increased expression of filaggrin (FLG) and loricrin (LOR) in HEKs. B. longum increased the efficacy of GOS to upregulate FLG and LOR expressions in HEKs. Oral administration of GOS increased fecal abundance of B. longum in mice. Oral administration of B. longum attenuated DNCB-induced skin inflammation, abnormal TEWL, AD-like skin, and deficiency of epidermal barrier proteins. Moreover, the combination of B. longum and GOS showed greater effects to improve DNCB-induced skin inflammation, abnormal TEWL, AD-like skin, serum IgE levels, IL-4 over-expression, and the deficiency of epidermal barrier proteins than the administration of B. longum alone. Conclusions B. longum and GOS improve DNCB-induced skin barrier dysfunction and AD-like skin.
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