Patently Apple reported an Apple’s patent published in Europe titled “Display with Embedded Pixel Driver Chips” describing the method of fabricating Micro LED display panels with a display integration scheme that embed an array of LEDs on substrates with the front side up.
In the description of the patent application, Apple used figures of flexible and foldable display to illustrate how the approach of LED pixel driver chips can be embedded on different display panels.
(Image: World Intellectural Property Organization)
With the patent application, Apple proposed a new manufacture technique of “replacing TFT substrate with a matrix of microcontrollers bonded to the substrate to create Micro LED display by integrating a matrix of Micro LEDs on the microcontroller substrate.” According to the application, each microcontroller can switch or driver one or more Micro LED.
Apple describes a front side redistribution layer (RDL) that forms over the chips and an insulator layer forming the display substrate. On top of the RDL layer are placed Micro LED. This structure may allow for significant freedom in designing and locating the pixel driver chips. Conductive pillars can be formed through the insulating layer for connecting to chips that can be placed on a back side of the display substrate. The method thus allows display panels to be curved, foldable and flexible.
Roger Chu, Research Vice President of LEDinside, pointed out that foldable and flexible displays are the area where Micro LED could take an advantage since Micro LED is based on semiconductor component with a strong structure. Compared to OLED, Micro LED also featured with better reliability and longer life time.
The new patent released by Apple with display fabrication on foldable and flexible substrate might mark the rising opportunity for Micro LED.