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- 摘要
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- 实验方案
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Thermal and optical properties of high-density GaN micro-LED arrays on flexible substrates
摘要： Flexible GaN-based micron-size light-emitting diodes (μLEDs) with high brightness and low power-consumption are a promising technology for next-generation wearable displays. While, integrating GaN μLEDs onto flex can provide more functionality, the bending-induced strain and potential self-heating of the device are the challenges that degrade the device performance on plastic platforms. Here, a novel “paste-and-cut” approach to selectively transfer GaN μLEDs from sapphire substrates onto flexible platforms demonstrated the effectiveness of various intermediate metallic-bonding layers and LED geometries on the optical properties and performance of the flexible devices. Computational thermal simulation of the flexible μLEDs showed effective heat dissipation for devices mounted on plastic platforms bonded using a 0.5 μm thick Cu metallic pad to create stable optical emission (λ = 450 nm) under current densities of > 1 A/cm2. Through a finite-element analysis (FEA), it was determined that the applied stress-induced strain near the quantum wells of the μLEDs can be negligible for devices with diameters smaller than 20 microns. Experimental verification supported the simulation results; the diodes were found to be electrically and thermally stable when copper electrode layers > 600 nm thick was used to bond the LEDs onto the plastic platforms. The I-V characteristics of the μLEDs showed no measurable degradation after transfer onto the flexible substrate with a turn-on voltage of 2.5 V. Commensurate to the FEA simulations, no measurable optical wavelength shift was observed for LED having a diameter of 20 microns when driven at a current density of 1 A/cm2 under different mechanical strain.
关键词： Flexible Display,Heat Transfer,Invariant Emission,GaN Micro-LED
更新于2025-09-23 15:21:01
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Interfacial fracture investigation of patterned active matrix OLED driven by amorphous-Si TFTs under film-type packaging technology
摘要： Considering the structural stability for active-matrix organic light-emitting diode (AMOLED) application, the reliability of lamination interfaces has become a major concern. The comprehensive influence of structural design integrated with material selections should be carefully examined and estimated. The layout effect of embedded pattern defined layer (PDL) plays an important role in the actual AMOLED architecture. To address the issue of stress-induced failure mechanism of PDL under external loads due to external bending, fracture mechanics-based finite element analysis integrated with Tsai–Hill criterion is utilized in this research. Simulated results indicate that the declined thickness and 45° oblique angle design for PDL prevents the failure occurrence of concerned interfaces. Notably, multiple neutral axis (NA) occurs when an extra-low Young’s modulus of pressure-sensitive adhesive (PSA) is considered. Multiple NA design prevents brittle fracture failure occurrence in gas barrier architecture, while these multiple NAs shift to adjust to the foregoing location. Accordingly, a proper arrangement of these multiple NAs in AMOLED packaging encapsulation through the selection of material characteristics and stacked thickness of PSA thin film has the advantage to enhance structural reliability.
关键词： Multiple neutral axis,Layout pattern effect,Flexible display,Interfacial fracture
更新于2025-09-23 15:19:57
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Ethylene glycol-assisted ultrafast synthesis and luminescent properties of novel multifunctional EuSr2F7 and TbSr2F7 nanostructures for WLEDs, displays and anti-counterfeiting
摘要： In this paper, novel EuSr2F7 and TbSr2F7 nanostructures were successfully prepared via an ultrafast wet-chemical route at room temperature. The elemental compositions, morphology, luminescent behaviors, thermal stability, decay curves and quantum yield of the as-prepared samples were investigated. The fabricated white light-emitting diodes (WLEDs) devices exhibited excellent CRI and CCT values. The security inks and soft polydimethylsiloxane films were prepared for potential anti-counterfeiting and flexible display applications. Eventually, under low accelerating voltage and filament current, the as-prepared samples showed strong cathodoluminescence emission intensity. The above results suggest that the novel EuSr2F7 and TbSr2F7 nanostructures with outstanding luminescent performances could be promising for field-emission displays (FEDs), WLEDs, flexible display films, and anti-counterfeiting applications.
关键词： nanostructures,FEDs,anti-counterfeiting,WLEDs,flexible display films
更新于2025-09-12 10:27:22
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13.3: <i>Invited Paper:</i> The Standardization and Performance Evaluation of Flexible Display Devices
摘要： In the flexible display devices to standardization, the development course and present situation of IEC/TC110 flexible display devices (WG8) are both introduced. Due to the variability of flexible display, the test method of flexible displays is different from traditional displays. At present, many studies have been focusing on the measuring methods of optical characteristics from the vantage point for curved displays, visual assessment of the mechanical reliability and environment tests of flexible display devices are also discussed. Considering the usage environment, the establishment of a reasonable environmental mechanical composite test method is investigated. With the development and the application of flexible and stretchable display devices, the scientific method will be developed.
关键词： mechanical reliability,Flexible display,environment tests,IEC/TC110
更新于2025-09-10 09:29:36
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11.4: The Fabrication of Flexible Electrofluidic Display Arrays Based on PEN Substrate
摘要： Flexible electrofluidic display (FLEFD), as one of the most promising reflective display technology, has drawn an increasing attention in recent years. In this study, we report the fabrication process for the FLEFD based on the flexible PEN film with ITO layer on the surface. The hyflon material was selected as the hydrophobic insulator layer to control the fabrication temperature below 170°C, and the photoresist was used to manufacture the pixel grids. After oil filing and the electrical properties and optical packaging process, properties of FLEFD were both taken into consideration. The results showed that FLEFD presented good display characteristics. The driving voltage of flexible device was 14V when the bending radius of curvature was 10cm. Furthermore, response time for the device was 18ms, and the aperture opening ratio was 42.5%.
关键词： Flexible display,fabrication process,electrowetting,PEN substrate
更新于2025-09-09 09:28:46
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Dependent Analyses of Multilayered Material/Geometrical Characteristics on the Mechanical Reliability of Flexible Display Devices
摘要： A generalized solution for the bending stress/strain expression of flexible display composed of multi-stacked thin films is presented in this letter. Flexible display comprises an arbitrary number of films combined with dissimilar thicknesses and linear-elastic mechanical characteristics. Specific consequences for alternate layered systems are estimated to reveal the elementary trends of the dependencies of normalized bending strain and neutral axis (N.A.) position on the modulus and thickness ratios of the concerned layers. An actual architecture of flexible display is also provided as an example to calculate the results and is compared with the simulated predictions of finite element analysis. With various material selections of cover plate, the induced stresses on transparent conducting film and the position of the N.A. plate are separately investigated. Moreover, the impact of bending radius on the mechanical reliability of flexible encapsulation is also found. The presented results serve as a design guideline for the infrastructure optimization of flexible display devices without electrical failures.
关键词： Flexible display,bending stress,multi-layered architecture,analytical solutions
更新于2025-09-09 09:28:46
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43.1: <i>Invited Paper:</i> Advances in Flexible Display Materials
摘要： One of the trends in today’s Display technology is flexible displays. It enables consumer electronic products to have form factors of being curved, foldable, bendable and rollable. DowDuPont Electronics & Imaging Display Technology has been heavily investing in flexible technologies. It provides liquid polyimide for customers’ high-quality flexible substrates on which display devices are built.
关键词： Flexible display,Polyimide (PI),Colorless,OLED
更新于2025-09-04 15:30:14