硅片平整度知识介绍.ppt

硅片平整度知识讨论IQC 2006-4-201硅片平整度知识讨论主要内容如下：主要内容如下：1、硅片平整度定义；、硅片平整度定义；2、硅片平整度测量；、硅片平整度测量；3、硅片平整度规范、硅片平整度规范4、硅片使用中异常举例、硅片使用中异常举例2平整度SEMI 标准 关键字注释习惯用语SEMI 标准用语新SEMI 标准 关键字注释TTVGBIR Global flatness back ideal rangeTIR GFLRGlobal flatness front least-squares rangeSTIRSFQRSite flatness front least-squares rangeLTVSBIRSite flatness back ideal rangeFPDGFLDGF3DGlobal flatness front least-squares deviationGlobal flatness front 3 point deviation3TTV(Total Thickness Variation)定义：定义：TTV=a b (SEMI标准中为标准中为GBIR )说明：1.参考平面 B为Wafer背面4TIR(Total Indicator Reading)定义：定义：TIR=|a|+|b|(SEMI标准中为标准中为GFLR )说明：1.参考平面(bf)G为距上表面所有点截距之和最小的平面；5FPD(Focal Plane Deviation)定义：定义：FPD=Max(|a|,|b|)(SEMI标准中为标准中为GFLD )说明：1.如果|a|b|，则FPD取正值；反之取负值；2.参考平面G(bf)为距Wafer上表面所有点截距之和最小的平面；6Warp定义：定义：Warp=|a|+|b|说明：1.参考平面M为距曲面Median plane所有点截距之和最小的平面；2.不考虑重力影响；7Bow定义：定义：Bow=1/2*(b-f)说明：1.参考平面 W 以Wafer上三点确定，此三点组成一等边三角形2.凸的Wafer Bow值为正，凹的Wafer Bow值为负；3mm1201208LTV(Local Thickness Variation)定义：定义：LTVi=ai bi i=1,2,3,4,.,n(SEMI标准中为标准中为SBIR)说明：1.参考平面B为Wafer背面；2.LTV max=Max(LTV1,LTV2,.,LTVn)9STIR(Site Total Indicator Reading)定义：定义：STIRi=|ai|+|bi|i=1,2,3,4,.,n (SEMI标准中为标准中为SFLR)说明：1.参考平面G i通过每一单元块的中心且平行于wafer上表面的拟合平面bf G；2.G为距单元块上每一点截距最小的平面；3.STIR max=Max(STIR1,STIR2,.,STIR n)；10STIR/L-Site(Site Total Indicator Reading)定义：定义：STIRi/L=|ai|+|bi|i=1,2,3,4,.,n (SEMI标准中为标准中为SFQR)说明：1.参考平面bf G i为距单元块上每一点截距最小的平面；2.STIRi/L max=Max(STIR1/L,STIR2/L,.,STIRn/L)；11SFPD/L-Site定义：定义：SFPD i/L=Max(|ai|,|bi|)i=1,2,3,4,.,n (SEMI标准中为标准中为SFQD)说明：1.|a|b|,取正值；|a|b|,取正值；|a|b|,取负值；2.参考平面G i通过每一单元块的中心且平行于wafer上表面的拟合平面bf G；3.SFPD/G max=Max(SFPD 1/G,SFPD 2/G,.,SFPD n/G)14SEMI StandardFQAMeasurementMethodReferenceSurfaceReferencePlane and AreaReferencePlane and AreaReferenceSurfaceSite SizeandArrayParameterParameterGBIRGF3RGF3DGFLRGFLDSF3RSF3DSFLRSFLDSFQRSFQDSBIRSBIDRangeRangeDeviationRangeDeviationRangeDeviationRangeDeviationRangeDeviationRangeDeviationParameterParameterParameterParameterParameterReferencePlane and AreaReferencePlane and AreaS-TIRS-FPDS-TIRS-FPDS-TIRS-FPDLTVS-FPDSemi用语現行习惯用语TTVTIRFPDTIRNTVFPDFront Ref.Center Focus3pointBest FitSite Best FitBack Ref.Center FocusSite FlatnessGlobal FlatnessFrontBackBackFront3Point3Point(全面)Ideal(全面)(最小二乗法)bfLeast Squares(全面)Least Squares(全面)(bf)Least Squares(site)Ideal(全面)参考面的选取(表面 or 背面)参考平面的設定(bf or 3pt)又称理想平面(Flatness Quality Area)15Flatness Tools Principle:Capacitance sensor(ADE)Wafertbcat=a-b-cRing Spacing16局部平整度测量边缘问题Partials Inactive Site Setup17局部平整度测量边缘问题Partials Active Site Setup Green lines indicates partial sites.18 两种方式测量结果差异举例-SFQD TrendChanged Measurement to Partial Sites ActiveChanging to Partial Sites Active Increased SFQD on a sample of Epi wafers Inactive 0.17um Active 0.24um19平整度SEMI 标准 ITEMSPOLISHED WAFER EPITAXIAL WAFER1.0um Design Rule Twin-Tub CMOS0.35um Design Rule Twin-Tub CMOS0.35um Design Rule DRAMTTV(GBIR)10um-5umTIR(GFLR)-3umSFQD-=0.5um18x18mm=0.23um22x22mm=0.35um22x22mmBOW60um-WARP60um-SEMI STANDARD FOR 150mm(SEMI M1 AND M11)20常用硅片STIR数值举例上图为各厂家上图为各厂家上图为各厂家上图为各厂家STIRSTIR均值中的均值中的均值中的均值中的MAXMAX、MEANMEAN、MINMIN比较比较比较比较21工艺过程硅片平整度变化擦片后、一次/牺牲氧化（900C）后、SIN（700C）后采用光刻PENKIB1设备进行平整度测量，每片的平整度三次测量结论：数值差异不大 平整度有增大的趋势平整度有增大的趋势22聚焦异常Flatness Values测量TTVTIRBest FitSFPD Best FitBow Best FitWarp Best FitS1 Defocus5.6201.943-0.271-0.73 6.16S2 Defocus6.9552.443-0.241-20.6142.14S3 Defocus5.2332.363+0.314-17.0035.77S233.0301.600-0.292+0.51 7.31S25 OK2.8681.793-0.297-17.8238.35EPI Not Proc 3.0651.801-0.224-异常与异常与TTV相关相关23 聚焦异常Flatness Values测量SFQDSite Best FitCurrentSBIDBack RefSFLDFront RefBest FitSF3DFront Ref3 PointS1 Defocus-0.271-1.311-0.940-0.966S2 Defocus-0.241-1.649-1.204-1.262S3 Defocus+0.314-1.502-1.151-1.184S23-0.292-0.757-0.951-1.012S25 OK-0.297-1.043-0.940-1.035EPINot Proc-0.224-0.565-0.744-0.730defocus does not correspond to site flatness,such as SFQD,SBID,SFLD,and SF3D.242024/5/21 周二25