Study On Fabrication And Photoelectric Performance Of High Luminous Efficiency GaN-based LED Chip

Compared with flip-chip and vertical LED chips,GaN-based front-mounted structure LED chips have the advantages of simple preparation process,low cost,and high yield.Due to the current solid-state lighting and backlight industry,cost and mass production are mainly considered,so traditional front-mounted chips are still used as Mainly,improving the light emitting efficiency of LED chips has become the research focus of experts at home and abroad.Therefore,this article will research and make LED formal chips that conform to the current mainstream LED industry.Through simulation modeling and experiments,the technical approach of how to improve the light-emitting efficiency of GaN-based LED chips is studied,and the process fabrication,photoelectric performance testing and analysis of GaN-based front-mounted structure LED chips are carried out.The purpose of this study is how to improve the light emitting efficiency of LED chips.Two types of LED chips of different sizes were selected for research,that is,a chip with a size of 200um*480um(8mil*19mil)and a chip with a size of 150um*255um(6mil*10mil).The following work was done respectively:(1)For the first The size of the chip,a periodic circular hole microstructure was fabricated on the ITO surface with a thickness of 33nm,and the photoelectricity test and analysis were performed on the fabricated sample.(2)For the chip of the second size,the ITO layer was fabricated with a circular circle.Hole microstructure,and optimize its electrode structure to further improve the light output efficiency of the LED chip.For 200um*480um LED chips,periodic microstructures were fabricated on the ITO surface.Tracepro software was used to simulate the light extraction efficiency of LED chips with periodic microstructures on the ITO surface based on Monte Carlo method.The simulation results show that compared with LED chips without periodic structure in the ITO layer,the light extraction efficiency of LED chips with periodic structure is significantly improved,and the light extraction efficiency of LED chips with large circular microstructures on the surface of ITO is the most improved,6.98%.The experimental results show that when a 20mA current is passed,the output optical power of the LED chip sample with the periodic microporous structure is increased by up to 7.56%compared to the LED chip without the periodic structure in the ITO layer.For the 150um*255um LED chip,the electrode was optimized based on the microporous structure on the surface of the ITO layer.The 3D simulation model of the finite element analysis software COMSOL was established to simulate and analyze the active layer of the LED chip with different electrode structures.The influence of the current density distribution results in an optimized structure.The experimental results show that with an input current of 20mA,the output light power of the LED chip with microstructure on the ITO surface and optimized N-electrode structure is 32.7mw,which is 9%higher than the output light power of traditional LED chips,and the light output efficiency Increased 8.28%.