- Membership : Micro LED Next Generation Display Industry Member Report
- Update : 2017-07-14
- Update Frequency : Quarterly
- Format : PDF
Mass transfer is a critical technology for Micro LED manufacturing, transferring Micro LED to a target backplane quickly and accurately will be one of the topics that manufacturers need to work on the most as well as on improving UPH and yield.
LEDinside assesses the possibility on mass production of Micro LED according to Six Sigma. The transfer yield must be Four Sigma or higher so that the product has a chance to be commercialized but still with high processing and repair costs, while the transfer yield must be Five Sigma or higher to achieve mature commercialized products with competitive processing cost.
Chip bonding and wafer bonding cannot be applied to mass transfer due to low production capacity and high time cost, therefore, currently wafer bonding can be adopted to develop Micro LED technology and products featuring low pixel volume with the existing machines, while challenge exists in production capacity and time cost, so various thin-film transfer related technologies will be the mainstream in future.
In view of the current situation, Micro LED will be firstly applied to indoor display, smart watch and smart bracelet, due to the high difficulty in transfer technology and various application products with different pixel volume, some manufacturers conduct R&D with existing wafer bonding equipment and take the application products with low pixel volume as targets to shorten the development period, also some manufacturers directly develop thin-film transfer technology, which required more resource investment and longer development period because the equipment needs to be adjusted even redesigned, moreover, there will be more manufacturing problems.
Five thin-film transfer technologies include electrostatic adsorption, Van der Waals force-enabled transfer printing, laser ablation, phase-change transfer and fluidic assembly. The fluidic assembly is a high-speed assembly approach that achieves high UPH for various product applications, also it can reduce assembly time and cost greatly.