On June 6, a research team led by Yongtaek Hong, a professor in the Department of Electrical and Information Engineering at Seoul National University, announced that the team has developed a new technology to connect Micro LEDs to flexible and stretchable devices.
It is reported that the researchers used a dip-transfer coating technique to selectively pattern the adhesive precursor onto the surface of the micro device. The adhesive contains ferromagnetic particles that can be self-assembled into anisotropic chains using a magnetic field. This method can provide low contact resistance for device interconnection and no electrical interference between fine-pitch terminals.
In addition to being able to assemble flexible and stretchable Micro LED arrays, this technology can also be used to create a Micro LED display device that can be attached to the skin to detect human body temperature and visualize data on the display.
The research team explained that the new technology overcomes the problem of low elasticity and flexibility of electrodes and substrates caused by the harder properties of anisotropic conductive film materials, as well as the problem of low bonding stability caused by softer adhesives.
The research team said that using this new technology, the team integrated the micro IC driver and LED display unit into a flexible PCB, realizing an ultra-small wearable display and sensor system that is smaller than existing commercial micro IC chips.
The research team said that this new technology can systematically integrate high-performance microelectronic devices while maximizing the mechanical properties of flexible and stretchable systems. This technology will contribute to the commercialization of flexible displays.
It is reported that the research was supported by Samsung, and the research paper has been published in the academic journal Nature Electronics.