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Roles of oxygen interstitial defects located in the In-Ga-Zn-O (IGZO) thin films prepared by atomic layer deposition were investigated with controlling the cationic compositions and gate-stack process conditions. It was found from the spectroscopic ellipsometry analysis that the excess oxygens increased with increasing the In contents within the IGZO channels. While the device using the IGZO channel with an In/Ga ratio of 0.2 did not show marked differences with the variations in the oxidant types during the gate-stack formation, the device characteristics were severely deteriorated with increasing the In/Ga ratio to 1.4, when the Al

Device scaling of oxide-channel thin-film transistors (TFTs) toward sub-micrometer regime has been an urgent issue to realize higher-resolution displays and 3-D structured electronic devices. The channel-shortening effect is a serious problem in implementing the oxide TFTs with short channel lengths. In this work, the short-channel effects (SCEs) of the In-Ga-Zn-O (IGZO) TFTs were investigated with the variations in channel composition when the channel length was varied from 3 μm to 500 nm. Effective channel lengths were examined to decrease with increasing the In contents, in which the reduction of the effective channel length was estimated to be 240 and 720 nm when the In/Ga ratio increased 0.7 to 1.4. The drain bias-dependent roll-offs in turn-on voltages, which typically correspond to drain-induced barrier-lowering (DIBL), also showed significant channel composition dependence. When the In/Ga ratio within the channel increased from 0.2 to 1.4, the DIBL coefficients were estimated from 22 to 244 mV/V for the devices with a channel length of 1 μm. The channel composition-dependent variations in the effective channel length were suggested to result from the inter-diffusion and redox reactions at interfaces between the channel and electrode layers. Alternatively, the contact resistances were also examined to play major roles in determining the SCEs with scaling the devices, especially when the In contents decreased in the channel composition. Thus, properly controlling the channel composition can be concluded as such an important issue for compromising both technical strategies to reduce the channel resistance and to suppress the reduction of effective channel length.

We present herein the first report of organic/inorganic hybrid thin-film encapsulation (TFE) developed as an encapsulation process for mass production in the display industry. The proposed method was applied to fabricate a top-emitting organic light-emitting device (TEOLED). The organic/inorganic hybrid TFE has a 1.5 dyad structure and was fabricated using plasma-enhanced atomic layer deposition (PEALD) and inkjet printing (IJP) processes that can be applied to mass production operations in the industry. Currently, industries use inorganic thin films such as SiNx and SiOxNy fabricated through plasma-enhanced chemical vapor deposition (PECVD), which results in film thickness >1 μm; however, in the present work, an Al2O3 inorganic thin film with a thickness of 30 nm was successfully fabricated using ALD. Furthermore, to decouple the crack propagation between the adjacent Al2O3 thin films, an acrylate-based polymer layer was printed between these layers using IJP to finally obtain the 1.5 dyad hybrid TFE. The proposed method can be applied to optoelectronic devices with various form factors such as rollables and stretchable displays. The hybrid TFE developed in this study has a transmittance of 95% or more in the entire visible light region and a very low surface roughness of less than 1 nm. In addition, the measurement of water vapor transmission rate (WVTR) using commercial MOCON equipment yielded a value of 5 × 10-5 gm-2 day-1 (37.8 °C and 100% RH) or less, approaching the limit of the measuring equipment. The TFE was applied to TEOLEDs and the improvement in optical properties of the device was demonstrated. The OLED panel was manufactured and operated stably, showing excellent consistency even in the actual display manufacturing process. The panel operated normally even after 363 days in air. The proposed organic/inorganic hybrid encapsulant manufacturing process is applicable to the display industry and this study provides basic guidelines that can serve as a foothold for the development of various technologies in academia and industry alike.

Acute traumatic posterior glenohumeral dislocation in association with a massive rotator cuff tear is rare. Moreover, only few cases with interposition of the long biceps head of the tendon has been described to prevent reduction in posterior dislocation of the shoulder. In addition, combined scapula fracture with posterior shoulder dislocation also extremely rare. We present a case of Irreducible posterior fracture and dislocation of shoulder with massive rotator cuff tear due to incarceration of biceps tendon. For the treatment arthroscopic in situ superior capsule reconstruction was performed using the long head of the biceps tendon with rotator cuff repair.

Thin-film transistor (TFT)-driven full-color organic light-emitting diodes (OLEDs) with vertically stacked structures are developed herein using photolithography processes, which allow for high-resolution displays of over 2,000 pixels per inch. Vertical stacking of OLEDs by the photolithography process is technically challenging, as OLEDs are vulnerable to moisture, oxygen, solutions for photolithography processes, and temperatures over 100 °C. In this study, we develop a low-temperature processed Al2O3/SiNx bilayered protection layer, which stably protects the OLEDs from photolithography process solutions, as well as from moisture and oxygen. As a result, transparent intermediate electrodes are patterned on top of the OLED elements without degrading the OLED, thereby enabling to fabricate the vertically stacked OLED. The aperture ratio of the full-color-driven OLED pixel is approximately twice as large as conventional sub-pixel structures, due to geometric advantage, despite the TFT integration. To the best of our knowledge, we first demonstrate the TFT-driven vertically stacked full-color OLED., To realize organic light-emitting diodes (OLEDs) with improved resolution for display applications, a method for achieving high yield device fabrication is needed. Here, the authors report vertically-stacked transistor-driven full-color OLEDs with photolithography-processed intermediate electrodes.

BACKGROUND: It remains unclear whether the deep layer of the rotator cuff is an articular layer of the supraspinatus (SS) or infraspinatus (IS), rotator cable, or superior capsule. Therefore, this study aimed to analyse the relationship between occupation ratios and delamination patterns of rotator cuff tears (RCTs). We hypothesised that the deep layers are related to the occupation ratios of the deep SS and IS sections. MATERIALS AND METHODS: A total of 265 patients with RCTs were retrospectively enrolled between 2013 and 2017 and divided into four groups: A, non-delaminated tear; B, delaminated tear with the deep layer equally retracted to the superficial layer; C, delaminated tear with the deep layer more retracted; D, delaminated tear with the superficial layer more retracted. Muscle volume was evaluated by measurement of each occupation ratio of the SS and IS, and the IS muscle was additionally divided into two areas, deep and superficial. RESULTS: The SS occupation ratio was significantly lower in group C than in the other groups (p = 0.009). Conversely, comparison of the IS occupation ratios revealed no significant intergroup differences. The occupation ratio of the superficial IS was significantly lower in group D than in the other groups (p = 0.003). In group C, the occupation ratios of the deep IS section were significantly decreased according to RCT size (p = 0.034). CONCLUSION: Our findings demonstrate that the superficial layers are related to the IS superficial section and the deep layers to the SS and IS deep sections. LEVEL OF STUDY: IV.

Vertical channel thin film transistors (VTFTs) have been expected to be exploited as one of the promising three-dimensional devices demanding a higher integration density owing to their structural advantages such as small device footprints. However, the VTFTs have suffered from the back-channel effects induced by the pattering process of vertical sidewalls, which critically deteriorate the device reliability. Therefore, to reduce the detrimental back-channel effects has been one of the most urgent issues for enhancing the device performance of VTFTs. Here we show a novel strategy to introduce an In–Ga–Zn–O (IGZO) bilayer channel configuration, which was prepared by atomic-layer deposition (ALD), in terms of structural and electrical passivation against the back-channel effects. Two-dimensional electron gas was effectively employed for improving the operational reliability of the VTFTs by inducing strong confinement of conduction electrons at heterojunction interfaces. The IGZO bilayer channel structure was composed of 3 nm-thick In-rich prompt (In/Ga = 4.1) and 12 nm-thick prime (In/Ga = 0.7) layers. The VTFTs using bilayer IGZO channel showed high on/off ratio (4.8 × 109), low SS value (180 mV dec−1), and high current drivability (13.6 μA μm−1). Interestingly, the strategic employment of bilayer channel configurations has secured excellent device operational stability representing the immunity against the bias-dependent hysteretic drain current and the threshold voltage instability of the fabricated VTFTs. Moreover, the threshold voltage shifts of the VTFTs could be suppressed from +5.3 to +2.6 V under a gate bias stress of +3 MV cm−1 for 104 s at 60 °C, when the single layer channel was replaced with the bilayer channel. As a result, ALD IGZO bilayer configuration could be suggested as a useful strategy to improve the device characteristics and operational reliability of VTFTs.

From the very first time that graphene was used as a transparent electrode for OLED applications, the emergence of active-matrix (AM)-graphene OLED displays has been envisioned. Realizing this expectation, however, turned out to be difficult. Two obstacles are the growth and transfer of a large-area graphene film and the patterning of a graphene film into pixels. To solve these problems, a process of patterning a graphene film without surface contamination was developed. The fabrication of OLED panels by the patterned graphene anode on Gen 2(370 × 470 mm)-sized and flexible substrates was successfully demonstrated. In this work, oxide TFT arrays were combined as a switching backplane, and a pixelated graphene OLED was used as an emissive layer, to realize AM-graphene OLED displays. To explore the technical feasibility of flexible AM-graphene OLED displays, the aforementioned components were formed on a flexible substrate. For commercial-level production, all the processes that were used were chosen to be compatible with the conventional display processes.

Since the late 20th century, there has been rapid development in the display industry. Only 30 years ago, we used big cathode ray tube displays with poor resolution, but now most people use televisions or smartphones with very high‐quality displays. People now want images that are more realistic, beyond the two‐dimensional images that exist on the flat screen, and digital holography—one of the next‐generation displays—is expected to meet that need. The most important parameter that determines the performance of a digital hologram is the pixel pitch. The smaller the pixel pitch, the higher the level of hologram implementation possible. In this study, we fabricated the world‐smallest 3‐μm‐pixel‐pitch holographic backplane based on the spatial light modulator technology. This panel could display images with a viewing angle of more than 10°. Furthermore, a comparative study was conducted on the fabrication processes and the corresponding holographic results from the large to the small pixel‐pitch panels.

Arthroscopic Bankart repair is generally accepted as the choice of treatment for labrum and glenoid rim restoration. Recently, the antegrade suture passer has been one of the widely used devices in arthroscopic surgery. This device saves time by combining tissue grasping, suture passage, and suture retrieval into one convenient step. In addition, a knotless anchor is also used for a Bankart repair to prevent knot-induced articular cartilage injuries. Arthroscopic Bankart repair usually uses two anterior portals (anterosuperior accessory portal and anteroinferior working portal) with one posterior viewing portal. The purpose of this technical note was to present a simple and easy technique for Bankart repair using a single anterior working portal with an antegrade suture passer and knotless anchors.

We developed a high definition holographic display with two different approaches. First approach is to adjust a wellknown display technology using a liquid crystal as an optical modulator. While merit of display technology is a large panel size, the challenge is to define a small pixel pitch and to reduce a crosstalk effect of a liquid crystal. Second approach is to adapt a silicon technology with a new optical modulator, Ge2Sb2Te5. Although we can easily define a small pixel pitch, we have to confront a small panel size. We will explain our solutions to overcome these issues.

Holographic display is known as the most realistic 3D display by creating real 3D image in front of observer. But there are tremendous technical hurdles in realizing electronic hologram. It is required to achieve very small pixel pitch SLM (spatial light modulator) for realizing electronic hologram using flat panel display. All the components of the unit pixel should be carefully redesigned and improved to maintaining same performance in spite of reduction of pixel pitch. The size of hologram image depends on the size of SLM. Therefore, the resolution of the SLM increases very fast as the reduction of pixel pitch in SLM. The driver chip and architecture should be developed to manage the large number of pixels with high speed. Novel unit pixel design for achieving 1μm pixel pitch will be presented. VST (vertically stacked transistor) structure will be introduced. In VST structure, the driving TFT is stacked on the data line. VST structure has the merits for reducing horizontal pixel pitch without introducing expensive high-definition lithography tool. The technology compatible with 0.5μm critical dimension can be used for fabrication of 1μm pixel pitch SLM. Alternative structure for achieving small pitch pixel is the adopting VTFT (vertical channel thin film transistor). VTFT means that the channel direction is vertical to SLM plane. The footprint of VTFT is very small, for required area is only the overlap region of active layer and source/drain layer. Cross-talk between adjacent pixels can interfere the rotation of LC molecule. This phenomenon will be very critical for accurate phase modulation for 1μm pixel pitch SLM. Novel concept for reducing cross-talk will be also presented with experimental results.

This paper discusses reconstruction of synthetic aperture Fourier hologram with unitary sampling on the SLM with non-squared pixel structure. A numerical procedure is introduced to meet different sampling ratio of the hologram. Experimental verification is provided.

We present high-mobility back channel etch Al–In–Zn–Sn–O/In–Zn–O (IZO) double-layer channel thin-film transistors (TFTs). The field-effect mobility of 53.2 $\text{cm}^{2}/\text{V} \cdot \text{s}$ , threshold voltage of 0.5 V, and subthreshold swing of 0.15 V/decade were obtained with a thin IZO-inserted double-layer channel TFT. The positive bias stability was improved with an IZO-inserted double-layer channel. We fabricated 13-stage ring oscillators, which exhibited an oscillating frequency of 296 kHz at ${V} _{\text {DD}} = {20}$ . These results demonstrate that the proposed double-layer channel oxide TFT can be used for demanding applications such as backplane devices for ultrahigh resolution display.

Holographic projection displays provide high diffraction efficiency. However, they have a limited projection angle. This work proposes a holographic projection display with a wide angle, which gives an image of size 306 m m × 161 m m at 700 mm and reduced speckle noise. The solution uses single Fourier lens imaging with a frequency filter and hologram generation utilizing complex coding and nonparaxial diffraction. The experiment was performed with a 4K phase-only spatial light modulator (SLM) to prove the high efficiency of the developed numerical tools. Optical reconstruction shows high resolution and high image quality achieved from a single frame. Hence, displaying video at a full frame rate of the SLM is possible.

We fabricated high performance 2-µm-channel oxide thin-film transistors (TFT) on glass substrate for 7-μm-pixel-pitch spatial light modulator (SLM) panel for digital holographic applications. Furthermore, we succeeded in the demonstration of the sub-micron TFTs, which is an inevitable route to the next-generation spatial light modulation devices with near 1-μm pixel pitch.

The mechanism of formation of metal–oxide–metal (M–O–M) bonds in solution-processed metal oxide semiconductors can vary depending on the types of precursors used. To date, metal-alkoxides or metal-chloride precursors have mainly been studied; therefore, efforts to improve the device characteristics of oxide thin-film transistors (TFTs) have been limited to these types of precursors. On the other hand, systematic studies to optimize the experimental conditions (e.g. thickness and annealing atmosphere) of oxide TFTs made by using new types of precursors have rarely been reported. In this study, we successfully demonstrate high-performance solution-processed Zn–Sn–O TFTs by using a metal-carboxylate precursor, tin(II) 2-ethylhexanoate, and optimizing the oxide thickness and thermal annealing conditions. To determine the optimum thickness of Zn–Sn–O, we prepared 3 types of active layers with different thickness combinations of ZnO and SnO2. In addition, we found that oxygen gas in the annealing process maximizes the formation of M–O–M bonds and decreases the number of trap sites in the thickness-optimized active layer, leading to dramatically enhanced device performances. As a result, the optimized Zn–Sn–O TFTs based on tin(II) 2-ethylhexanoate exhibit excellent mobility exceeding 22 cm2 V−1 s−1, which is an order of magnitude higher than that of the previously reported Zn–Sn–O TFTs based on the same precursor and very comparable to the mobility levels obtained from conventional solution-processed metal-oxide TFTs. We believe that our approach will enrich the current family of tin precursors and provide another option for resource-friendly, low-cost, and high performance Zn–Sn–O semiconductors.

Background: Recently, several in vitro biomechanical studies that used dual small locking plate fixation for humeral shaft fractures have investigated. However, in vivo studies about dual plate fixation for humeral shaft fractures are limited. The purpose of our study was to report the outcomes of dual small plating for humeral shaft fractures in comparison with those of single large fragment plating. Methods: Sixty consecutive patients who underwent an open reduction internal fixation for humeral shaft fractures at our institution from September 2014 to December 2017 were included. Single 4.5-mm locking compression plate (LCP) fixation was used in the first 40 cases, and dual 3.5-mm LCP fixation was used in the final 20 consecutive cases. Data were collected to define patient characteristics, injury mechanism, clinical outcomes, time to surgery, operative time, estimated blood loss, and complications. Using simple radiography during the follow-up period (6, 12, 24, and 52 weeks after surgery), the shoulder and elbow joint ranges of motion (ROM) were also evaluated. Results: Demographic data, time to surgery, surgical time, and estimated blood loss had no significant differences between the two groups. No significant differences were observed in nonunion rate and union rate 3 months after surgery. However, two patients (5%) in the single 4.5-mm LCP fixation group showed metal failure and breakage. No significant differences were found in postoperative shoulder and elbow ROM. Three patients (7.5%) in the single plating group and one patient (5%) in the dual plating group developed radial nerve palsy after surgery. No vascular injury and deep infection were observed in either group. Conclusion: For diaphyseal humeral fractures, dual 3.5-mm LCP fixation to the humerus is a possible treatment choice. This method showed satisfactory union rate, ROM, and complication rate, without increasing surgical time, in comparison with the conventional single 4.5-mm LCP fixation. Level of evidence: III

The purpose was to evaluate the relationship between GTA, CSA, and the delamination patterns of RCTs. This study included 315 patients with RCTs from 2014 to 2018, retrospectively. The subjects were divided into 5 groups: Group A, control group; Group B, non-delaminated tear; Group C, delaminated tear with equally retraction of articular and bursal layer; Group D, articular layer more retracted delaminated tear, and Group E, bursal layer more retracted delaminated tear. In conclusion, large GTA and CSA were associated with rotator cuff tears. However, there was no difference of GTA and CSA according to the delamination patterns.