Transfer or delivery of micro light-emitting diodes for light-emitting diode displays

As the next-generation display technology, microscale light-emitting diode (μ-LED) displays have attracted significant attention recently. For applying μ-LEDs as direct emissive pixels in everyday display applications, many chips in a relatively small-sized wafer must be relocated and distributed quickly over a wide screen area via so-called transfer technology. After a brief review of current conventional transfer technologies for placing μ-LEDs on a wide screen, for perspective, a new and versatile delivery technique for μ-LEDs is presented, in which an LED chip is converted to a ball shape in order to facilitate handling and processing of μ-LEDs for practical applications. Plausible procedures including the formation, arrangement, and removal of the plastic ball are discussed to envision potential impacts of the technology.