Gan Led The New Structure Of The Epitaxial Growth And The Development Of The Led Chip

GaN-based LED with high power and high efficiency in new energy light-emitting diodes attract much attention due to its wavelength involved in blue, green, and blue-green range. External quantum efficiency is low in the current situation, and this paper presents two aspects to improve this defect:the epitaxial process and chip process using the new GaN-based LED structure, and gets better results. The article first using MOCVD to growth a new P-type Pits structure in GaN-based epitaxial, and greatly enhance the brightness; followed by the professional optical simulation software Crosslight APSYS on ODR chip and ordinary LED chip with optical simulation, and we studied the advantages of ODR chip on light extraction efficiency and luminous intensity. Next we confirmed the advantages of ODR LED from the optics, colorimetry. and reliability through taped experimental production of high-power ODR LED and ordinary LED. Specifically contain the following three parts1. The experiment focuses on the growth of micron-level surface roughening above the P-type GaN in LED to improve the brightness, and testing results show that:Compared with ordinary LEDs, the samples with Pits structure have a higher PL and EL intensity with relative increasing by90%and nearly39%, respectively; on the size of B2310, the samples with Pits structure have a high brightness,and higher than the Flat structure sample of relative18.9%; while its average forward voltage is only3.17V, decreased about2.5%compared with ordinary samples; the samples with Pits structure also have a better reverse electronic characteristics. At a low current of20mA, electro-optical conversion efficiency of the samples with Pits structure relatively increase more than22.4%of the ordinary sample, and the voltage drop of0.042V compared with ordinary samples. The samples with Pits structure have a more uniform current proliferation, better overall quality, and less linear dislocation. All samples change small in optical and electronic parameters after aging96h and have passed results in aging experiments.2. In this part of experiment, the APSYS software is used to simulate optical and electrical properties of the high-power multi-quantum-well GaN-based ODR LED in3D chip. The simulation results showed that:IV characteristics and the internal quantum efficiency of both the ODR LED and ordinary LED is basically the same because the ODR LED is mainly to improve LED light extraction efficiency; the spectral curve of ODR LED and ordinary LED is basically the same, but the spectral intensity of the ODR LED significantly higher than that of ordinary LED, ODR LED has a blue light reflection which comes from multi-quantum well; at a current of350mA, the light intensity of the ODR LED is106.49mcd, increasing more than18.93%of ordinary LED. However, the three-dimensional heat figure shows that the heat of the ODR LED is slightly higher than ordinary LED structure. Experimental simulation results give some guidance and advice to the next tapeout experiments.After the pre-optical simulation study, in this parts GaN-based InGaN/GaN MQW power LEDs are fabricated based on the existing technology conditions through a simple processing, and their optical, electrical, and color properties are also tested. Results show that the luminous intensity of the chips with ODR has an improvement of244mcd over that with the ordinary chips and the ODR LED’s luminous flux, the efficiency and the color purity is improved by6.04%,5.74%,78.64%respectively. One of the advantages of the ODR LED is its low color temperature, which is great lower than that of the ordinary LED.