资源描述:
《MCVD工艺制备光纤(制造工艺).ppt》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、MCVD工艺关键技术蒋作文光纤的四大制造技术VAD(轴向汽相沉积)OVD(外部汽相沉积)MCVD(改进的化学汽相沉积)PCVD(等离子体化学汽相沉积)MCVD工艺简介MCVD工艺步骤1——RecipeDevelopmentMainvariablesforeachprocessstepsarefollowing:Gasflows:bubblercarriergas,O2,He,Cl2,SF6etc.PreformtemperatureCarriagespeedSootboxpressureRampingofrele
2、vantparametersMCVD工艺步骤2——TubepreparationTypicalMCVDproductiontubeisconstructedfromthreequartztubes,whichareweldedtogetherpriortoMCVDprocess.inlettube:lowqualityquartzsubstratetube:highqualitysyntheticsilica,formsfinalpreformexhausttube:lowqualityquartzsleevin
3、gtube:syntheticsilicaMCVD工艺步骤3——FirePolishing/EtchingPurpose:Tocleantubeouterandinnersurfacetoimprovepreformquality.Temperature:1850-2200CReactantflows:O2+fluorinesourceforetchingSF6+O2MCVD工艺步骤4——CladdingandcoredepositionCladdingdepositionPurpose:depositionof
4、protectionbarrierforcore.Temperature:1900-2100oCTypicalreactantflows:SiCl4,POCl3,O2,HeCoredepositionPurpose:depositionofrefractiveindexdifferenceTemperature:1900-2200oCTypicalreactantflows:SiCl4,GeCl4,O2,HeMCVD工艺反应机理SiCl4+O2=SiO2+2Cl2GeCl4+O2=GeO2+2Cl24POCl3+
5、3O2=2P2O5+6Cl24BCl3+3O2=2B2O3+6Cl2热泳效应热泳现象是指在温度梯度不为零的气体或悬浮体中,粒子向较冷区域运动的现象。热泳速度正比于温度梯度,而与粒径无关。MCVD工艺步骤5——CollapsingPurpose:toproduceglassrodforjacketingandfiberdrawingTypically2to5forwardand1backwardstepsTemperature:2000-2400oCChlorineusedasadryingagentMCVD工艺步
6、骤5——Preformanalysisdimensionalandopticalparameterevaluation.importantprocessandqualitycontroltoolMorepreformanalysisPreformdimensionsPreform,claddingandcorediametersfromdifferentanglesandlongitudinalpositionsRefractiveindicesSubstratetube,claddingandcorefromd
7、ifferentlongitudinalpositionsCutoff,MFD,ChromaticdispersionPreformnon-circularity(preform,cladding,core)Preformconcentricity(preform,cladding,core)MCVD工艺步骤6——RodintubesleevingPurpose:enlargepreformsizetoimproveMCVDproductivityTypicalfinalpreformsize:40to80mmT
8、emperature:>2000CVacuumsuctionbetweenrodandtubetoacceleratejoiningprocessFiberdrawingMCVD设备系统主要组成1.Lathe2.GasControlSystem3.PC/PLCControlSystem4.Gas&WaterSupply5.ExtractSystems.SGCMCVDMCV