Simulation of thin film thickness distribution for thermal evaporation process using a scanning linear source

Abstract

Thermal evaporation process is the main process involved in the production of OLED displays and with the trends toward larger substrate size and display resolution, film thickness uniformity must be carefully controlled in order to implement exact pixel data. To secure stable film thickness uniformity on the substrate area, thin films are deposited on large‐area glass substrates via thermal evaporation process using a linear source. We designed a linear source and mathematical model was developed to describe the system with a focus on the linear source. Then, system parameters were determined to guarantee uniform thickness using computer‐based simulation, replacing wasteful actual experiments, followed by carrying out experiments based on the determined parameters. After the deposition process, data from the mathematical model and experiments was compared and the resulting agreement was good, verifying the validity of the proposed method. Consequently, by applying the proposed method, display manufacturing process related to thermal evaporation can be controlled within a tight tolerance in order to maximize the production yield rate.

Customized 2D Structures for High Throughput Electromigration Measurements

“…Using a deposition distance of 120 mm, Al thin films were deposited on the substrates simultaneously from all three sources. This was done in order to increase the thin film thickness uniformity across the surface of the substrates by weakening the effect of the thickness distribution cosine law . Evaporation rates of 1 nm s −1 were used for each source and a final thin film maximum thickness of 300 nm was obtained.…”

Vacuum‐Deposited Inorganic Perovskite Light‐Emitting Diodes with External Quantum Efficiency Exceeding 10% via Composition and Crystallinity Manipulation of Emission Layer under High Vacuum

“…Metal halide perovskites continue to be the subjects of tremendous research and development efforts because of their excellent optoelectronic properties, including high absorption coefficients, success of organic LEDs (OLEDs), which are manufactured predominantly through vacuum deposition, rather than solution methods, it is expected that highly efficient all-vacuum-deposited PeLEDs would also inherit the advantages of vacuum processing: layer-by-layer stacking giving more capable structures, fabrication of meter-sized substrates, precise control over the layer thickness and uniformity, and batch-to-batch reproducibility. [29][30][31] Nevertheless, intriguingly, even with great efforts exerted by many researchers, the efficiency and brightness of vacuumprocessed PeLEDs have lagged those of their solution-made counterparts. The highest EQEs of vacuum-deposited PeLEDs have typically been 5-8%, but they have usually been associated with low maximum brightness.…”