Investigation On Micro-LED Array Isolation Technology Based On Ion Implantation

Miniature light-emitting diodes(Micro-LEDs)are miniature,array light-emitting diodes that are realized by mesa etching on the basis of traditional light-emitting diodes(LEDs).Compared with conventional LEDs,they have high current density,high light output density,The advantages of response frequency,high response bandwidth and uniform current extension have great application prospects in the fields of light display,visible light communication,optical tweezers and neuromedicine.Among them,in the field of light display,compared with display technologies such as liquid crystal display(LCD)and organic light emitting diode(OLED),Micro-LED display technology has high brightness,high contrast,high resolution,high reliability,long life,and low energy.Consumption and other advantages are considered as a new generation of light display technology.However,as the device size decreases to the micron level,factors such as size effects,edge effects,and dislocation density will exacerbate device performance degradation.The edge effect mainly manifests as the device size decreases,the proportion of sidewall damage introduced by mesa etching gradually increases,and the effect on the device is more significant.Traditionally,LED devices prepared by dry etching will inevitably introduce an isolation table,and then introduce a certain degree of edge damage.As the size of the device decreases,the ratio of edge damage to the total device area will increase significantly,so that the effective working area of the device Decrease.In addition,the mesa etching isolation also generates side wall dangling bonds,which leads to increased reverse leakage current of the device.On the other hand,mesa etching also introduces deep-level defects,forming non-radiative recombination centers,which increases the non-radiative recombination rate of the device.Large,external quantum efficiency is reduced,thereby reducing the effective working area of the device.When the micro-LED device is scaled down to 10 ?m,device edge damage will cause the device's reverse leakage current,radiation recombination efficiency,and the effective working area of the device will be severely degraded.Therefore,the problem of sidewall damage greatly limits the micro-LED device's Development and application.Aiming at the problem of device side wall damage caused by mesa etching,this paper proposes a method to achieve device isolation by ion implantation to avoid the introduction of device side mesa.We prepared four types of 4 ?m,6 ?m,8 ?m,and 10 ?m through different ion implantation conditions.At the same time,the horizontal structure(implanted p-Ga N layer)and the vertical structure(implanted n-Ga N layer)Micro-LED devices were prepared?and the electrical isolation effect of devices after different ion implantation of n-Ga N and p-Ga N is compared and analyzed.The H and F ion implantation profiles werecharacterized by secondary ion mass spectrometry.The electrical and optical properties of the samples were tested using Agilent high-voltage probe station and integrating sphere test system.The main tasks include:(1).Micro-LED device structure design and lithography layout design based on ion implantation;(2).Research on Micro-LED ion implantation isolation process;(3).Test and analysis of photoelectric characteristics of Micro-LED devices in vertical structure and front-mounted structure;(4).Analyzing the optical characteristics of Micro-LED arrays prepared under different injection conditions;(5).Performance test analysis of Micro-LED devices of different sizes.