AlGaN multiple quantum well deep‐ultraviolet micro‐light‐emitting diodes for high color conversion efficiency quantum dots display

Abstract

Displays based on inorganic micro-light-emitting diodes (micro-LEDs) are highly anticipated for next-generation technologies. AlGaN-based deepultraviolet (deep-UV) micro-LED as the excitation source for quantum dots display with high efficiency was reported in this paper. To achieve optimized electro-optical performance, deep-UV micro-LEDs with different electrodes were fabricated and analyzed in sizes from 200 Â 200 to 10 Â 10 μm 2 . At the same forward bias, the devices with Ti/Al-based electrodes achieved 10 times injection current and three times electroluminescence intensity than those with Cr/Al-based electrodes. The blueshift phenomenon of deep-UV light was observed from 292 nm at 2 A/cm 2 to 287 nm at 200 A/cm 2 with the increasing current density. By the excitation of deep-UV micro-LED, quantum dot film achieved high light conversion efficiency and optimized color rendering, as the converted color emission peak was separate from the pumping source. The high energy of deep-UV photons and the narrow emission bandwidth of QDs resulted in prominent color purity. The forward voltage and electroluminescence intensity uniformity of a 250 Â 250 micro-LED array with each pixel size of 30 Â 30 μm 2 were further discussed. The optical microscope images of green QD film pumped by a deep-UV micro-LED demonstrated its competitive application in the color-converted display.

Microdisplays: Mini‐LED, Micro‐OLED, and Micro‐LED

“…source, the UV-C micro-LEDs excitation exhibits high color conversion efficiency and optimized color rendering, [149] resulting in an ultra-wide color gamut.…”

“…[ 147 ] Furthermore, recent research efforts have spotlighted the UV‐C micro‐LEDs on the color‐conversion displays by tristimulus QDs. [ 148 ] Benefiting from the high QD absorbance and separated color emission from the pumping source, the UV‐C micro‐LEDs excitation exhibits high color conversion efficiency and optimized color rendering, [ 149 ] resulting in an ultra‐wide color gamut.…”

21‐4: Elevating the Light Output Power Density of Scaling‐down AlGaN Ultraviolet‐C Micro‐LED

“…The industry has heavily anticipated UV-C Micro-LED with AlGaN multi-quantum wells (MQWs) in recent years for its broad application in color conversion display (1)(2)(3), optical wireless communication (OWC) (4)(5)(6), and optogenetic neuroscience (7)(8)(9). Although the size-dependent characteristics of UV-C Micro-LED have been discussed in the latest reports (10)(11)(12), the elevating optical power density for ultra-fine devices is rarely addressed.…”

3.2: Elevating the Light Output Power Density of Scaling‐down AlGaN Ultraviolet‐C Micro‐LED

“…The industry has heavily anticipated UV-C Micro-LED with AlGaN multi-quantum wells (MQWs) in recent years for its broad application in color conversion display (1)(2)(3), optical wireless communication (OWC) (4)(5)(6), and optogenetic neuroscience (7)(8)(9). Although the size-dependent characteristics of UV-C Micro-LED have been discussed in the latest reports (10)(11)(12), the elevating optical power density for ultra-fine devices is rarely addressed.…”