芯片制造工艺流程简介

ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionLED芯片制造工艺流程简介范青青2011年5月18日ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion主要内容LED的简单介绍LED芯片制造流程简介ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionLED是LightEmittingDiode的英文缩写，中文称为发光二极管。发光二极管(LED)是由数层很薄的搀杂半导体材料制成，一层带过量的电子，另一层因缺乏电子而形成带正电的“空穴”，当有电流通过时，电子和空穴相互结合并释放出能量，从而辐射出光芒。LED的简单介绍：ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionLED芯片的应用：ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionLED芯片制造流程示意图：蓝宝石衬底（Al2O3)（衬底厂商提供）PSS工艺PatternedSapphireSubstrate图形化蓝宝石衬底减小反向漏电，提高LED寿命，增强发光亮度ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion生长外延层（EPI）蓝宝石衬底N-GaNP-GaN芯片前段工艺（wafer）芯片后段工艺（chip）ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion封装ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion晶片投入台阶光刻前清洗•打印流程卡、标签、分批次•防止混片•清洁晶片表面•防止台阶光刻后图形不标准ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionMesa光刻•用光刻胶做出Mesa图形•PR保护P型层，露出N电极位置N-GaN蓝宝石衬底P-GaNPRChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionMesa干法刻蚀•无光刻胶保护的地方被刻蚀到N型层•露出N电极处的外延层N-GaN蓝宝石衬底P-GaNPRN电极处发光区切割道ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionCBL沉积•CBL(CurrentBlockingLayer)电流阻挡层•具有扩展表面电流作用CBL光刻有光刻胶无光刻胶ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionCBL蚀刻•采用湿法蚀刻（氢氟酸）•将没有光刻胶保护的地方的SiO2蚀刻掉SiO2外延N型层外延P型层ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionITO沉积•ITO（铟锡氧化物），导电性和透光性好•作为电流扩展层，有利于芯片的光电性能N-GaN蓝宝石衬底P-GaNITOSiO2（底层）+ITO（顶层）ITOChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionITO光刻N-GaN蓝宝石衬底P-GaNITOPRITO•将需要ITO的区域（发光区）用光刻胶保护住，为下一步蚀刻做出图形SiO2（底层）+ITO（顶层）SiO2（底层）+ITO（中层）+PRITO（底层）+PR（顶层）ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionITO蚀刻•采用湿法蚀刻，用ITO蚀刻液蚀刻ITO（盐酸和氯化铁等），用HF酸蚀刻SiO2•将没有光刻胶保护的地方的ITO和SiO2蚀刻掉外延P型层外延N型层N-GaN蓝宝石衬底P-GaNPRITOITOSiO2（底层）+ITO（顶层）ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion预退火•进行高温热处理，可降低正向电压、有利于电流扩展层表面接触的形成，提高了出光效率ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionMetal光刻•用光刻胶形成电极图形有光刻胶无光刻胶N-GaN蓝宝石衬底P-GaNITOPRChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion灰化（Ashing）酸洗•等离子去胶：利用氧气、氮气等气体清洁芯片表面，使得光刻胶表面更平整，且可去除电极处的负胶提高电极粘附性ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletionN-GaN蓝宝石衬底P-GaNITOPRPadMetal蒸镀•沉积Cr.Ni.Au.Ti四种金属ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion剥离（lift-off）•将电极以外的金属剥离掉N-GaNSapphireP-GaNITOPadPad外延P型层MetalITOSiO2（底层）+Metal（顶层）ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion钝化层沉积•等离子体增强化学汽相沉积(PECVD)PlasmaEnhancedChemicalVaporDeposition）•用SiO2薄膜做钝化层，防止短路，避免杂质原子对芯片表面的吸附，保护芯片（ITO膜），提高发光效率ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion钝化层光刻•做出钝化层图形有光刻胶无光刻胶N-GaNSapphireP-GaNITOPadPadPRSiO2ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion钝化层蚀刻•采用干法蚀刻将没有光刻胶保护的地方的SiO2蚀刻掉外延层+SiO2外延层+金属层外延层+ITO+SiO2外延层+SiO2+ITO+SiO2N-GaNSapphireP-GaNITOPadPadSiO2ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion快速退火•进行高温热处理，模拟客户使用环境，对不良芯粒做一次筛选BST•模拟客户打线测试电极粘附性前段工艺结束ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion研磨减薄自动目检测试划裂分选包装、出货ChipProductionManagementTeam/3ESemiconductorIdeaVelocityCompletion谢谢！