本文選題：高壓LED　切入點：芯片制備　出處：《華南理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：高壓發(fā)光二極管(HV-LED)具有工作電壓高、驅(qū)動電流小等特點,可以解決多晶封裝過程中存在的可靠性問題,并減少電壓轉(zhuǎn)換過程中的能源損失,因此成為了國內(nèi)外的研究熱點。本文針對正裝結(jié)構(gòu)Ga N高壓LED芯片制備及光電性能進行研究,主要工作如下:為提升Ga N基高壓LED芯片的出光效率,在藍寶石背面設(shè)計制備了4對Ti3O5/Si O2(100nm/40nm)的分布布拉格反射層(4-MDBR)和包括4-MDBR以及金屬鋁層(60nm)結(jié)構(gòu)的復(fù)合反射鏡(4-MDBR-Al)。在20m A的注入電流下,4-MDBR-Al結(jié)構(gòu)的高壓LED芯片的出射光功率為294.4m W,相對于只有4層DBR結(jié)構(gòu)(4-MDBR)的出射光功率提升了4.6%。針對如何提高側(cè)面出射光功率從而提升其光效進行了光學(xué)仿真計算,結(jié)果表明芯片形狀為正方形或長方形時,有效出光效率最高;側(cè)面微結(jié)構(gòu)形狀為圓形凹凸相間排列的復(fù)合結(jié)構(gòu)時,有效出光效率最高;進一步分析隔離溝槽間距對出光效率的影響,結(jié)果表明在無側(cè)面微結(jié)構(gòu)的情況下,有效光效極大值點在30μm處,而在有側(cè)面微結(jié)構(gòu)的情況下,有效光效極大值點在50μm處。為提升Ga N基高壓LED芯片的出光性能,優(yōu)化芯片發(fā)光單元之間隔離溝槽的寬度。本文在制備側(cè)面微結(jié)構(gòu)的基礎(chǔ)上設(shè)計了4種不同隔離溝槽寬度(10μm、20μm、30μm以及40μm)的Ga N基高壓LED芯片,并采用正裝工藝進行制備,對其進行光電測試,實驗結(jié)果表明隔離溝槽寬度為20μm的高壓芯片的光電性能最佳。注入電流為20 m A時,正向電壓50.72 V,輸出光功率373.64 m W,電光轉(zhuǎn)換效率36.83%。采用鏡面鋁基板和陶瓷基板進行四顆芯片串聯(lián)形式的COB封裝對比測試,結(jié)果表明基于鏡面鋁基板封裝的正向電壓、輸出光功率、飽和光功率、飽和電流、光輸出效率、光衰及溫度造成的藍光峰值波長紅移都優(yōu)于陶瓷基板,當注入電流為20m A且基板溫度為20℃時,鏡面鋁基板封裝的HV-LED器件的正向電壓是198.9 V,光輸出效率達122.2 lm/W。
[Abstract]:High voltage light-emitting diode (HV-LED) has the advantages of high working voltage and low driving current, which can solve the reliability problem in the process of polycrystalline packaging and reduce the energy loss in the process of voltage conversion. Therefore, it has become a research hotspot at home and abroad. In this paper, the fabrication and optoelectronic properties of Ga N high voltage LED chip are studied. The main work is as follows: in order to improve the light efficiency of gan high voltage LED chip, On the back of sapphire, four pairs of Ti3O5/Si O _ 2 O _ 2N _ (100 nm / / 40 nm) distributed Bragg reflectance layer (4-MDBR) and a composite mirror (including 4-MDBR and aluminum layer / 60nm) structure were designed and fabricated. The output power of the high-voltage LED chip with 4-MDBR-Al structure at 20mA injection current is as high as 4-MDBR-Al. 294.4mW, compared with only 4-layer DBR structure 4-MDBR, the output power is increased by 4.6m. the optical simulation calculation is carried out on how to increase the side light output power and improve its light efficiency. The results show that the efficient light output efficiency is the highest when the chip shape is square or rectangular, and the maximum effective light output efficiency is when the shape of the microstructure is a composite structure with circular concave and convex phase arrangement. The effect of the spacing of isolated grooves on the light efficiency is further analyzed. The results show that the maximum of effective light efficiency is at 30 渭 m in the absence of side microstructures, while in the case of side microstructures, the maximum of effective light efficiency is at 30 渭 m. The maximum of effective light efficiency is at 50 渭 m. In order to improve the output performance of gan based high voltage LED chip, On the basis of fabricating side microstructures, four kinds of gan based high voltage LED chips with different isolation groove widths (10 渭 m, 20 渭 m, 30 渭 m and 40 渭 m) were designed and fabricated. The experimental results show that the high voltage chip with isolation groove width of 20 渭 m has the best optoelectronic performance, and when the injection current is 20 Ma, The forward voltage is 50.72 V, the output optical power is 373.64 MW, and the electro-optic conversion efficiency is 36.83.The COB package of four chips in series is tested by using the mirror aluminum substrate and the ceramic substrate. The results show that the output optical power is based on the forward voltage of the mirror aluminum substrate package. The peak wavelength red shift of blue light caused by saturation optical power, saturated current, optical output efficiency, light decay and temperature is superior to that of ceramic substrate. When the injection current is 20 Ma and the substrate temperature is 20 鈩，

本文編號：1642190