蓝宝石作为衬底的LED芯片工艺

LED工艺简介LED发光管是怎样练成的衬底材料生长或购买衬底LED结构MOCVD生长芯片加工芯片切割器件封装Sapphire蓝宝石2-inch衬底片氮化物LED发光管的器件结构及发光机理electrons电子空穴复合发光P欧姆接触N欧姆接触蓝宝石或碳化硅MOCVD外延蓝宝石缓冲层N-GaNp-GaNMQW第一步清洗有机物金属离子第二步n区光刻刻蚀Cl2+Bcl3+Ar去胶3#液p电极蒸发P电极光刻P电极腐蚀KI+I2去胶丙酮+酒精P电极合金O2N电极光刻N电极蒸发N剥离N退火N2P压焊点光刻P压焊点蒸发P压焊点剥离钝化层沉积气体，功率钝化层光刻钝化层刻蚀钝化层去胶丙酮中道终测检验减薄划片裂片扩膜划片,裂片工作流程图划片前晶片背面划片后背面划片后,侧视图裂片后,侧视图扩膜后,正视图测试分检LED:What’sinside?electrodessemiconductorchipepoxydomebondwires“silvercup”reflectorDesignGrowthProcessingPackagingCharacterizationApackagedLEDDifferentpartsofanLEDProcessflow:RadiometryPhotometryPowerWatt(W)lumen(lm)PowerperunitareaW/m2lm/m2=lux(lx)PowerperunitsolidangleW/srlm/sr=candela(cd)Photometryisjustlikeradiometryexceptthateverythingisweightedbythespectralresponseoftheeye光学知识Solidangle:sr=2(1-cos(θ/2))立体角:如何理解光通量(Lumen)和发光强度(Mcd)470nmLED:3000mcd(20mA)P*62.139(lm)/Sr(15Deg)=3cdP*62.139/0.0537=3cdP=0.00259W=2.58mW市场上: