Reverse-Tapered LVT Barrier Wall for OLED Sealing

The sealing structure is divided into multiple functional layers: a first barrier wall protruding from the lower electrode, a second barrier wall with reverse-tapered shape on top of the first barrier wall, and a thin film encapsulation unit. This segmentation allows each layer to perform specific sealing functions, effectively protecting the organic light-emitting element while maintaining manufacturing feasibility through modular construction

The barrier walls are constructed using composite material systems with the second barrier wall containing LVT inorganic material including tin oxide. This composite approach combines materials with different properties to achieve superior barrier performance against oxygen and moisture penetration, enhancing reliability without requiring overly complex structural designs

The LVT inorganic material exhibits a viscosity transition at a specific temperature range. By controlling the heating parameters during manufacturing to reach this viscosity transition point, the material becomes more flowable and can automatically fill and conform to the desired barrier wall geometry. This parameter-based control achieves high manufacturing precision for the reverse-tapered barrier wall structure without requiring complex fabrication processes

The low temperature viscosity transition (LVT) of the inorganic material including tin oxide is exploited during manufacturing. When heated to the viscosity transition temperature, the material transitions from a rigid state to a more fluid state, enabling it to flow into and conform to the precise reverse-tapered shape of the barrier wall structure. After cooling, it solidifies to maintain the precise geometry, achieving high manufacturing precision through controlled phase transition rather than complex machining or deposition processes