太阳能电池photoresist技术中文版.ppt

Phase Shift Mask Patterning EUV 深紫外 l = 10 to 14 nm Higher resolution Projected application ~ 2010 0.1 mm and beyond X-ray lithography Similar to proximity printer Difficult to find pure X-ray source Challenge on mask making Unlikely will be used in production X-ray Printing E-Beam Used for making mask and reticles Smallest geometry achieved: 0.014 mm Direct print possible, no mask is required – Low throughput Scattering exposure system (SCALPEL) looks promising – Tool development – Reticle making – Resist development 光刻总结 光刻：临时的图形转移过程 IC生长中最关键的工艺 需要：高分辨率、低缺陷密度 光刻胶：正和负 工艺过程：预烘、底胶旋涂、PR旋涂、前烘、对准曝光、后烘PEB、显影、坚膜、检测 下一代光刻技术：EUV和电子束光刻 Etch 刻蚀 熟悉刻蚀术语 比较：干法刻蚀、湿法刻蚀 IC工艺中四种被刻蚀的材料和主要的刻蚀剂 IC工艺的刻蚀过程 注意刻蚀工艺中的危险 Definition of Etch Process that removes material from surface Chemical, physical or combination of the two Selective or blanket etch Selective etch transfers IC design image on the photoresist to the surface layer on wafer Other applications: Mask making, Printed electronic board, Artwork, etc. 栅掩膜对准 Gate Mask Alignment 栅掩膜曝光 Gate Mask Exposure Development/Hard Bake/Inspection Etch Polysilicon刻蚀多晶硅 Etch Polysilicon 继续 Strip Photoresist 剥去光刻胶 Ion Implantation Rapid Thermal Annealing 刻蚀术语 刻蚀速率 选择比 刻蚀均匀性 刻蚀剖面 湿法刻蚀 干法刻蚀 RIE：反应离子刻蚀 刻蚀速率 Δd = d0 - d1 (?) is thickness change and t is etch time (min) PE-TEOS PSG film, 1 minute in 6:1 BOE at 22 °C, Before etch, t = 1.7 mm, After wet etch, t = 1.1 mm 刻蚀均匀性 圆片上和圆片间的重复性 Standard Deviation Non-uniformity标准偏差不均匀性 N points measurements Max-Min Uniformity 最大最小均匀性 刻蚀选择比 Selectivity is the ratio of etch rates of different materials. Selectivity to underneath layer and to photoresist 举例 Etch rate for PE-TEOS PSG film is 6000 ?/min, etch rate for silicon is 30 ?/min, PSG to silicon 刻蚀剖面 刻蚀剖面 Wet Etch 湿法刻蚀 Wet Etch Chemical solution to dissolve the materials on the wafer surface The byproducts are gases, liquids or materials that are soluble in the etchant solution. Three basic steps, etch, rinse and dry Wet Etch P