本文選題：硅襯底 + 圖形襯底��； 參考：《南昌大學(xué)》2014年博士論文

【摘要】：以GaN基LED芯片為基礎(chǔ)的固態(tài)照明器件具有發(fā)光效率高，壽命長，響應(yīng)速度快，發(fā)光強度隨電流和脈沖寬度近線性變化，能在劇烈振動和惡劣環(huán)境下工作，不含環(huán)境有害物質(zhì)等優(yōu)點，成為新一代通用照明燈具的首選。隨著研究的深入和產(chǎn)業(yè)的發(fā)展，GaN基發(fā)光二極管的材料生長和器件制造技術(shù)已經(jīng)取得了長足進步，器件效率和可靠性也有顯著提升；特別是硅襯底GaN LED外延技術(shù)和芯片制造技術(shù)的成功實施，芯片成本進一步下降，加速了LED燈全面取代白熾燈和熒光燈進入通用照明領(lǐng)域的進程。 在此背景下，本文開展了對硅襯底GaN基材料和器件生長的研究。論文首先對Al合金掩膜微圖形化Si(111)襯底上GaN材料的側(cè)向外延生長進行了研究；然后，研究了同溫cap層和cap層厚度對綠光InGaN/GaN MQWs LEDs量子阱材料質(zhì)量和芯片發(fā)光性能的影響，以及濕法表面粗化對藍光LED芯片取光效率的提升作用；最后，對硅襯底GaN垂直結(jié)構(gòu)大功率發(fā)光二極管的可靠性進行了研究分析。通過上述研究，本論文取得了以下主要結(jié)果： 1.提出了用于硅襯底GaN材料選區(qū)外延生長的Al-Si合金掩膜技術(shù)。通過在Si(111)襯底表面蒸鍍150金屬Al，經(jīng)光刻工藝制作Al金屬圖形，然后高溫1200℃下進行合金擴散，獲得了Al-Si合金掩膜的圖形化硅襯底。實驗表明，在Al-Si合金掩膜區(qū)不會生長GaN，因此，Al-Si合金技術(shù)是Si襯底上選區(qū)外延生長GaN材料的一種有效掩膜方法。 2.通過優(yōu)化Al-Si合金條形掩膜參數(shù)和GaN外延生長條件，成功地在Al-Si合金掩膜微圖形化Si(111)襯底上的周期為1mm1mm方塊區(qū)域內(nèi)生長出無裂紋GaN連續(xù)外延膜，，并通過在方塊之間Al-Si掩膜區(qū)的硅襯底內(nèi)產(chǎn)生裂紋，實現(xiàn)了應(yīng)力釋放，從而有效地解決了硅襯底GaN外延膜發(fā)生龜裂的難題。 3.通過引入阱后同溫GaN cap層，成功地實現(xiàn)了對InGaN/GaN多量子阱綠光LED低溫生長的阱層InGaN材料的保護作用。研究表明，cap層厚度在一定范圍內(nèi)增加，InGaN阱層的In組分升高且分布更均勻，InGaN材料質(zhì)量和量子阱界面特性變好。具有25cap層的綠光器件的外量子效率(EQE)及EQE最高值對應(yīng)的電流密度分別是15cap層器件的1.39倍和10倍，文中對此給出了相應(yīng)解釋。 4.經(jīng)過工藝優(yōu)化，研制的厚度為25cap層結(jié)構(gòu)的硅襯底垂直結(jié)構(gòu)綠光LED芯片，經(jīng)封裝在350mA直流驅(qū)動下(電流密度35A/cm2)，主波長為519nm，內(nèi)量子效率40.3%，工作電壓2.99V，光功率達235mW，這是目前報道的硅襯底綠光發(fā)光二極管最好水平。 5.通過引入500Torr高壓條件下生長的p-GaN層，在具有大V型坑結(jié)構(gòu)的InGaN/GaN藍光LED外延結(jié)構(gòu)中，成功地實現(xiàn)了對量子阱區(qū)V型坑的填平作用，芯片反向漏電下降，器件發(fā)光效率增大；通過工藝優(yōu)化，研制的具有此結(jié)構(gòu)外延片制造的垂直結(jié)構(gòu)大功率藍光LED芯片在350mA直流驅(qū)動下(電流密度35A/cm2)，主波長為450nm，內(nèi)量子效率達79.5%，硅膠封裝器件的工作電壓為3.05V，光功率達595mW，與藍寶石襯底藍光LED市場產(chǎn)品的先進水平持平，從而有力地表明硅襯底LED是一條行之有效的半導(dǎo)體照明新技術(shù)路線。
[Abstract]:The solid-state lighting based on GaN based LED chip has high luminous efficiency, long life, fast response, near linear change of light intensity with current and pulse width. It can work in severe vibration and bad environment and does not contain environmental harmful substances. It has become the first choice for new generation of general lighting lamps and lanterns. The development of material growth and device manufacturing technology for GaN based light-emitting diodes has made considerable progress, and the efficiency and reliability of the device have been greatly improved, especially the successful implementation of GaN LED epitaxial technology and chip manufacturing technology on silicon substrate, the cost of the chip is further reduced, and the rapid replacement of incandescent lamps and fluorescent lamps by the LED lamp has been added. The process of using the lighting field.
In this context, a study on the growth of GaN based materials and devices on silicon substrate is carried out. First, the lateral epitaxial growth of GaN materials on Si (111) substrate of Al alloy mask is studied. Then, the quality and chip luminescence properties of the same temperature cap layer and cap layer thickness on the green InGaN/GaN MQWs LEDs quantum well materials are studied. The effect of the wet surface coarsening on the efficiency of the blue light LED chip is improved. Finally, the reliability of the high power GaN diode with the vertical structure of the silicon substrate is studied and analyzed.
1. the Al-Si alloy mask technology for the epitaxial growth of GaN material on silicon substrate is proposed. By evaporation of 150 metal Al on the surface of Si (111) substrate, the Al metal graph is made by photolithography. Then the alloy diffusion is carried out at high temperature 1200 C, and the graphical silicon substrate of the Al-Si alloy mask is obtained. The experiment shows that the growth of the Al-Si alloy mask will not grow. GaN, therefore, Al-Si alloy technology is an effective mask method for epitaxial growth of GaN materials on Si substrates.
2. by optimizing the strip mask parameters of Al-Si alloy and the growth conditions of GaN epitaxy, the crack free GaN continuous epitaxial film is successfully grown in the 1mm1mm block region on the Al-Si alloy mask micrographic Si (111) substrate, and the stress release is realized by producing a crack in the silicon substrate of the Al-Si mask region between the blocks. The problem of cracking of GaN epitaxial film on silicon substrate has been solved.
3. through the introduction of the well GaN cap layer after the well, the protection of the well layer InGaN material for the low temperature growth of the InGaN/GaN multi quantum well green LED is successfully realized. The study shows that the thickness of the cap layer is increased in a certain range, the In group of the InGaN well layer is higher and the distribution is more uniform, the quality of the InGaN material and the properties of the quantum well interface become better. The 25cap layer is of the 25cap layer. The external quantum efficiency (EQE) of the green device and the current density of the highest EQE value are 1.39 times and 10 times of that of the 15cap layer device, respectively.
4. through the process optimization, the silicon substrate vertical structure green light LED chip with the thickness of 25cap layer is developed. The chip is encapsulated in the 350mA DC drive (current density 35A/cm2), the main wavelength is 519nm, the internal quantum efficiency is 40.3%, the working voltage is 2.99V, and the light power is 235mW, which is the best level of the present silicon substrate green light emitting diode.
5. by introducing the p-GaN layer grown under the high pressure of 500Torr, in the InGaN/GaN blue LED epitaxial structure with a large V pit structure, the filling of V pits in the quantum well area is successfully realized, the reverse leakage of the chip and the luminous efficiency of the device are increased, and the vertical structure made of this structural epitaxial piece is developed through the process optimization. The high power blue light LED chip is driven by 350mA DC (current density 35A/cm2), the main wavelength is 450nm, the internal quantum efficiency is 79.5%, the working voltage of the silicon rubber package device is 3.05V, the light power is 595mW, and the advanced level of the blue light LED market product of the sapphire substrate is flat. Thus the silicon substrate LED is an effective semiconductor. Lighting new technical routes.
【學(xué)位授予單位】：南昌大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TM923.34

【參考文獻】

相關(guān)期刊論文 前2條

1 肖友鵬;莫春蘭;邱沖;江風益;;Si襯底GaN基藍光LED老化性能[J];發(fā)光學(xué)報;2010年03期

2 汪延明;熊傳兵;王光緒;肖宗湖;熊貽婧;江風益;;不同基板1W硅襯底藍光LED老化性能研究[J];光學(xué)學(xué)報;2010年06期

本文編號：1949627