45‐2: Invited Paper: Micro‐LED Displays: Key Manufacturing Challenges and Solutions

Abstract

Micro-LED displays offer potential advantages such as high brightness and low energy consumption; however mass adoption requires that manufacturing yield and cost targets are met. In this presentation we explore key manufacturing requirements and present solutions for MOVCD epitaxy and mass transfer to enableMicro-LED display adoption for consumer applications.

Mini-LED and Micro-LED: Promising Candidates for the Next Generation Display Technology

“…The first one is to be able to fabricate high performance Blue, Green and Red microLEDs, considering that there is a reduction of performance when device size is reduced. However, it is generally admitted that the main difficulty for making such displays is to make the transfer of the microLEDs onto the large area TFT backplane [4], since this technical step does not exist in present display technologies. Among the challenges, one need to make both a mechanical and an electrical connection between the two parts.…”

High performance color‐converted micro‐LED displays

“…Micro‐LED display is expanding rapidly in recent years because of its outstanding features such as low power consumption, nanosecond response time, long lifetime, high dynamic range, and wide color gamut . However, the high‐yield mass transfer process of micro‐LEDs from semiconductor wafer to glass substrate remains a challenge . To achieve full‐color micro‐LED displays, the most commonly used method is to grow red, green, and blue (RGB) micro‐LEDs on different wafers, and then assemble them into matrices on the same thin‐film transistor (TFT)‐based glass substrates through mass‐transfer, which requires precise alignment for each pixel.…”

“…[1][2][3][4] However, the high-yield mass transfer process of micro-LEDs from semiconductor wafer to glass substrate remains a challenge. 5,6 To achieve full-color micro-LED displays, the most commonly used method is to grow red, green, and blue (RGB) micro-LEDs on different wafers, and then assemble them into matrices on the same thin-film transistor (TFT)-based glass substrates through mass-transfer, which requires precise alignment for each pixel. Moreover, the light emission efficiency and degradation rate of RGB micro-LEDs are different; as a result, it may need complicated driving circuit to maintain the color rendering index during operation.…”

P‐8.9: Full‐color GaN‐based LED Micro‐display Integrated with Dynamic Color Filter

“…Pixel transfer is to grow red, green, and blue (RGB) micro-LEDs on different wafers, and then transfer them to the same substrates. But if the pixels of micro-LEDs are very small and of large numbers, it will be very difficult to achieve high transfer yield and efficiency so that the resolution of the display will be limited [4,5]. What's more, the driving circuit might be very complicated to balance the brightness as the light emission efficiency and degradation rate of RGB micro-LEDs are different.…”

“…One of the color conversion layer are processed as following. The R/G/B color conversion materials, like quantum dots(QDs), phosphors or fluorescent dyes, are separately arranged on light-emitting surface of each pixel by aerosol jet printing or lithography [6,7]. This configuration does not need color filters.…”