Fabrication And Performance Study Of AlGaInP-Based Red Micro-LED Array Display

The application of Micro-LEDs has received widespread attention due to their superior performance advantages,including high brightness,high resolution,high contrast,and low power consumption.These benefits make them highly attractive for a range of applications such as wearable devices,electronic device screens,biomedicine,lens-free microscopes,and visible light communications.With their remarkable advantages in pixel density,display brightness,and lifetime,Micro-LEDs are considered to be the ultimate goal in the display sector,surpassing the well-established LCD and OLED technologies.Moreover,the preparation of red Micro-LEDs using the quaternary alloy material AlGaInP is essential for the creation of full-color displays.In this paper,we have fabricated Micro-LED devices with different diameters and MicroLED array displays based on AlGaInP.We have also conducted a study of their optoelectronic properties.This paper investigates the ohmic contacts of AlGaInP red Micro-LEDs,which are essential for the preparation of high-performance devices.We employed a range of techniques,including photolithography,electrode vapour deposition,and stripping steps,to fabricate p/n ohmic contacts with different metal structures.The specific contact resistivity of each ohmic contact was assessed using a circular transmission line model,and post-annealing was conducted to optimize the ohmic contacts.The impact of annealing temperatures and times on the ohmic contacts was examined,and the underlying reasons for these effects were analyzed.The final choice was Ni/Ag/Ni for the p-side ohmic contact structure with a specific contact resistance of 4.45×10-5Ωcm2.The n-side ohmic contact structure was Pd/Ge/Ti/Pt with a specific contact resistance of 7.88 × 10-4Ω cm2.We successfully prepared AlGaInP-based red Micro-LED devices of varying sizes and Micro-LED array displays through epitaxial wafer etching,trench filling,and electrode vapour deposition steps.The optoelectronic performance studies of these devices demonstrated stable electrical properties and low leakage currents.Smaller devices exhibited superior spectral output stability,while larger devices displayed higher brightness and optical power density.We also prepared Micro-LED array displays measuring 0.5" in size and studied their optoelectronic properties,revealing uniform brightness and excellent spectral output stability.These displays featured a fixed pattern comprising over 50000 pixel dots,and observations of pixel dot morphology in different sections revealed relatively uniform morphology with almost no defective dots.Each pixel dot measured 10 μm in size,with a pitch of 12 μm and a pixel density as high as 2116 PPI.Overall,this study provides important insights into the preparation of high-performance AlGaInP-based red Micro-LEDs and holds significant reference value for future research in this field.This study provides some ideas for the preparation of high performance AlGaInP-based red micro-LEDs and has some reference significance.