OLED Inkjet Printing Temperature Control for Uniform Layer Thickness

The patent applies preliminary action by heating the substrate before ink jet printing to control solvent evaporation rate. The substrate is pre-heated to a specific temperature range (20-100°C) before the organic material solution is deposited, which prevents rapid and uneven solvent evaporation that would otherwise cause thickness non-uniformity. This preliminary temperature control ensures uniform drying and consistent layer thickness throughout the manufacturing process.

The patent changes physical parameters by controlling substrate temperature, drying atmosphere (nitrogen or vacuum), and drying time. By adjusting the substrate temperature within 20-100°C and controlling the drying environment, the solvent evaporation rate is optimized to achieve uniform organic layer thickness while maintaining the simplicity of the solution coating process.

The patent optimizes processing parameters by controlling substrate temperature (20-100°C) and drying atmosphere (nitrogen or vacuum) to achieve the right balance between processing speed and thickness uniformity. The temperature is set high enough to enable rapid solvent evaporation for efficient processing, but controlled to prevent excessive evaporation that would cause thickness gradients. The drying time is also optimized based on the specific conditions used.

The patent employs an inert atmosphere (nitrogen) or vacuum environment during the drying process to control solvent evaporation. This inert environment prevents oxidative degradation of the organic material while allowing controlled evaporation rates that maintain thickness uniformity, thus achieving both fast processing and high precision.

The patent divides the manufacturing device into distinct functional modules: a substrate heating unit with independent temperature control, an ink jet printing unit, and a UV irradiation unit. Each module operates independently but coordinates seamlessly, allowing precise control of the organic layer formation process without creating an overly complex integrated system. The segmentation enables easier maintenance and optimization of each component.

The substrate heating unit serves multiple functions: it pre-heats the substrate before printing, controls solvent evaporation during drying, and can be integrated with the UV irradiation process. This multi-functionality reduces the need for separate dedicated components, thereby achieving uniform layer thickness without proportionally increasing device complexity.