Innovative stress-release method for low-stress flexible Al2O3 encapsulation films in OLED applications
Source abstract
Abstract
This study presents a low residual tensile stress, flexible thin film encapsulation with a 2 mm bending radius based on atomic layer deposition (ALD), specifically plasma-enhanced ALD (PEALD). By utilizing polydimethylsiloxane (PDMS) to release stress during deposition, we achieved a wrinkled morphology film that reduces stress magnitude from 10 3 to 10 2 compared to conventional Al 2 O 3 films. This wrinkled film enhances optical modulation to light extraction, increasing the external quantum efficiency (EQE) of organic light-emitting diode (OLED) by up to 14.95%. The water vapor transmission rate (WVTR) is 4.49 × 10 − 5 g/m 2 /day at 60 °C/90% RH, and the film retains about 90% of its initial properties after 10,000 bending cycles. This work introduces a novel solution for flexible ALD encapsulation, demonstrating ultra-flexible properties while improving device efficiency.
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Research context
OpenAlex topics: Organic Light-Emitting Diodes Research · Semiconductor materials and devices · Thin-Film Transistor Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (54)
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