用于移动显示器制造的飞秒激光加工Femtosecond laser processing for mobile display manufacturing

Displays are key components of many of today’s mobile electronic devices such as smartphones, digital cameras, mp3 players, etc. As the market for mobile electronics expands, displays are required to fulfil more and more challenging requirements for power consumption, image quality and definition, as well as robustness.

The next generation of mobile displays offers a wider color gamut, better image contrast and lower power consumption. They also benefit from wider viewing angles, faster response and more compactness due to their thin multilayer architectures. New technologies, such as flexible displays, make extensive use of organic LEDs technology (OLED), and present significant manufacturing challenges. Production yield for such displays are currently very low; due to the complexity and the multilayer structure of the displays (up to 20 different materials). Many units come out of the production line with defects and are then discarded. The presence of dead, over-bright pixels and other imperfections are considered unacceptable in such a high added-value consumer item. As the mtechnology extends to larger volumes and large panel displays, better production yield become critical for display manufacturers. Current laser processing technologies face limitations such as the sensitivity of organic material to heating and the low thickness of thin film layers.

Femtosecond lasers allow non-thermal ablation of materials, owing to the extremely short interaction time of the laser-matter interaction. Therefore machining precision can be significantly improved using femtosecond laser ablation as heat affected zone and debris generation is greatly reduced [1,2]. In addition, non-thermal process is crucial for selective removal of multi-layer organic polymers that are susceptible to heat.