光刻工艺培训--喷胶状态调整-.pptx

Dispense adjustmentpanc1Resist Dispense ParameterCoating process parameterPump Air-operator valveResist 2May 24Coating Process ParameterResist DispenseResist TemperatureResist Dispense systemPump type(pneumatic/motor driven,single/double stage)Resist Filter(material,type,pore size)Dispense line(length,diameter,material,nozzle diameter)Resist DispenseResist Dispense VolumeResist Dispense RateDispense Pump adjustmentMotor Flange Temperature3May 24Resist TemperatureOld style water jackedNew style water jackedResist temperature measurement at nozzle block possibleResist temperature measurement at nozzle block shows large error4May 24Resist TemperatureResist Temperature influence on uniformitymajor parameter to adjust coating uniformityrecommended setting range:21.0-24.0Cbest temperatures of different Resists at same track should be as close as possible(temperature settling time between two recipes)inside water jacked are just 7 cc of resist(no multiple dummy dispense before process start)Resist temperature Calibrationcalibration needs to be done regularly(every 3-6 month)watch for right measurement position(old and new style)Resist DispenseA low resist temperature will cause an additional suckback due to contraction of resist(adjust low initial suckback)A high Resist temperature will cause a dripping of Resist due to expansion of Resist(adjust a high initial suckback)5May 24Resist Dispense System-Pump typePneumatic driven Pumpsalready since long time in usenot for low dispense volumeslimited dispense volume repeatabilityno good dispense rate controllow investment costsIWAKI SB pumpMILLIPORE WCDS/WCDP pumpIDI PumpStepper Motor driven Pumpscan control low dispense volumegood to excellent dispense volume repeatabilitycan control low dispense rateshigh investment costIWAKI FT 100-1 pumpCYBOR 5120 pumpMILLIPORE GEN2MILLIPORE IntelliGENTEL RDS pump6May 24Resist Dispense System-Pump typeSingle Stage PumpsResist is dispensed through the filterDispense rate=filtration ratepoor dispense rate controlhigh stress on the ResistDispense start and shut off problemsproblems with high viscosity Resistair vent after filter difficultlow recovery timeless expensiveall pneumatic driven pumpsCYBOR 5120IWAKI FT 100-1Double Stage PumpsFirst stage pump filters the ResistSecond stage pump dispenses ResistFiltration rate independent from dispense ratelow stress on the Resistexcellent dispense rate control(multi rate possible)extended filter life timereduced maintenance requirementsefficient air vent includedlong recovery timesexpensiveMILLIPORE GEN2MILLIPORE IntelliGENMILLIPORE Photo250TEL RDS7May 24Resist Dispense System-Pump typeMillipore IntelliGENMillipore GEN2Millipore WCDSCYBOR 5120IDI 4008May 24Resist Dispense System-window of operation9May 24Resist Dispense System-Resist FilterNo Filtrationfor high viscosity Resist and Polyimidevery low stress dispenseLow COOMembrane Filtertoday mostly usedpore size and number of stacks depend on application(viscosity)membrane made from PTFE(some UPE)sometimes levelling agents first need to cover filter surface after installation(striations for 24h)PTFE filter need prewet with solvent prior to the use with ResistHollow Fibre Filterrelatively new on the markedno prewet necessaryfilter material:UPEnot yet tested for all chemicalsno experience with high viscosity ResistFilter live timedepend on used Resist(type and supplier quality)depend on used filter typedepend on used Pump typecontinuous(daily/weekly particle check is recommended)10May 24Resist Dispense System-Resist FilterSpontaneous Wettability of Typical Photochemical Filters11May 24Resist Dispense System-Dispense lineDispense line lengthas short as possiblelength in water jacked app 1mlimits maximum of applicable Resist Viscosity Dispense line inner diametermust fit to the applied resist viscosityif too small too large pressure dropif too large problems with air bubblesTEL standard:3.2 mm(3.0 mm in water jacked)replace damaged tubes!12May 24Resist Dispense System-Dispense lineDispense line assemblyline must be assembled straight upward(no ups and downs,no horizontal loops)if possible shorten dispense lineDispense line materialTEL standard:ultra pure PFAResist nozzleTEL standard Nozzle diameter:2.0 mm1.5 mm nozzles for low viscosity resists applicablewatch for nozzle cleanness(dummy dispense)watch for nozzle damages(nozzle is consumable)if comets on wafer first check the resist nozzle13May 24Resist Dispense VolumeMinimum Dispense Volume to cover the wafer and to achieve a good coating uniformity depends on:wafer sizeResist volume remaining on wafer at 1.0 m thickness150mm wafer:0.016cc200mm wafer:0.028cc300mm wafer:0.063ccResist viscosityResist solventPattern topographyLayer surface tension Process know howuniformity requirementsResist pump capabilities Currently used Dispense volumes for“1m Resists”14May 24Resist Dispense VolumeDry patch caused by:too low resist volumetoo low dispense ratetoo low dispense spin speedtoo low surface tension of substratetoo high surface tension of Resisttoo high pattern topography15May 24Resist Dispense RateDispense Rate=Dispense Volume/Dispense TimeDispense Rate highupsbetter surface coverageeasier control of dispense shut offdowns Dispense time lowdifficult to control uniformity on wafer(high dispense spin speed required)Dispense Rate lowupsDispense time higheasier control of uniformity on waferdownsdifficult to control dispense shut offsurface coverage difficult(high dispense spin speed required)16May 24Dispense RateDispense Rate depend on:Dispense volumevolume is chosen firstis calculated from volume and timeDispense timedispense time is chosen according to uniformity requirementsWafer wafer sizewafer surface tensionpattern topographyTechnical limitationminimum:lowest rate which pump can supportmaximum:highest rate which pump can support&highest possible filter pressure(single stage pumps)Limitations by the used Resistminimum:dispense splits into droplets(depend on the surface tension of the Resist)maximum:highest stress which the Resist can withstand(without cavitations and outgassing)Resist viscosity,surface tension,solvent system17May 24Resist Dispense adjustmentResist Dispense Parameter should be:Adjustable(parameter are“normal”)Reproducible(parameter are“known”)Critically are(independent of pump type):adjustment of dispense startadjustment of dispense rateadjustment of dispense shut offadjustment of suckback volumeadjustment of suckback speedHow to adjust the dispense:dispense into glass cylinder with app.45 angledroplet at dispense start or at dispense end will be easier visiblevariations in dispense rate will be visibleuse high speed camera(extremely expensive)18May 24Dispense Adjustment GEN2&IntelliGEN pumpPump PreparationBefore first usefill the dispense system with Resist(no filter prewet necessary)use the following pump parameter for filling:Dispense Volume:6.0 ccDispense Rate:1.5 cc/secPurge Volume:0.2 ccPurge Rate:0.5 cc/secVent Time:0.4 secwhen the pump is filled prime the system 50 times with the following parameter:Dispense Volume:1.5 ccDispense Rate:0.5 cc/secPurge Volume:5.0 ccPurge Rate:1.0 cc/secVent Time:2.0 secpurge the system by running the fill recipe another 50 times19May 24Dispense Adjustment GEN2&IntelliGEN pumpPump PreparationChange of Resistempty the system and change the filterif the old Resist is not compatible with the solvent of the new Resist empty the system and purge it first(before filter change)with the thinner of the old resistthen empty the system again and change the filterif the new Resist is not compatible with the thinner of the old Resist purge the system first with the thinner of the new Resist empty the system again and carry out same procedure as for“first use”Change of filtermake sure that no dummy dispense can occurchange the filter and run the“prime”procedure 50 times20May 24Dispense Adjustment GEN2&IntelliGEN pumpReadyFilterVentBarrierOutletInletIsolatePurgeResistDispense21May 24Dispense Adjustment GEN2&IntelliGEN pump1.DispenseFilterVentBarrierOutletInletIsolatePurgeResistDispense22May 24Dispense Adjustment GEN2&IntelliGEN pumpFilterVentBarrierOutletInletIsolatePurgeResistDispense2.Feed(fill pump)23May 24Dispense Adjustment GEN2&IntelliGEN pump3.FiltrationFilterVentBarrierOutletInletIsolatePurgeResistDispense24May 24Dispense Adjustment GEN2&IntelliGEN pump4.VentFilterVentBarrierOutletInletIsolatePurgeResistDispense25May 24Dispense Adjustment GEN2&IntelliGEN pump5.PurgeFilterVentBarrierOutletInletIsolatePurgeResistDispense26May 24IntelliGEN Pump recipeGeneral settings:before first use change the following factory default settings:EV=1(external valve used)VD=0(valve delay=0)RR=1(Recirculation recipe“1”)MM=3(multiple fixed-time/variable rate)SA!(save all)Never use the command DF!(sets all parameter back to factory defaults)Pump pressure:40 kPaPump vacuum:-75 kPa27May 24IntelliGEN pump assemblyResist PressureReservoirDrainExternal valveIntelliGEN pumpResist BottlePermanent vacuum is applied to the outlet valve if an external valve is used28May 24IntelliGEN pump dispense adjustmentsExternal Shut-off&Suck-back valveSuck-back volumeOutletInletSuck-back valveShut-off valveSpeedcontroller Shut-off(SC valve close)Speedcontroller Dispense start(SC valve open)Speedcontroller Suck-back velocity(SC suck-back)29May 24IntelliGEN pump dispense adjustmentsIdeal dispenseReal single rate dispenseMultirate dispensetimeDispense rateDispense StartThe Speedcontroller“dispense start”(SC valve open)has to bee always fully open!Suck-back at dispense start indicates air bubbles in dispense line or pumpdispense rate at dispense start is determined by pressure build up in dispense line and depend onResist viscositylength of dispense line(before and after external valve)inner diameter of dispense linekinks or sharp bends in dispense line(may also be inside water jacked!)if dispense rate rise up is too slow pre-dripping happens at dispense startthis problem can be corrected by:increased dispense rate at dispense start(multirate dispense)elimination of dispense line problems(kinks,length,loops,air bubbles)30May 24IntelliGEN pump dispense adjustmentsProgrammedRealtimeDispense rateDispense rate problemProgrammedRealtimeDispense rateMulti rate dispenseProgrammedRealtimeDispense rateMulti rate dispense problemDispense ratedispense splits into droplets if rate is too low(stepper motor steps visible)dispense rate splits into two parts if rate is reduced too strong(system“swings”)dispense rate may split into two parts if“SC valve open”is not fully opened31May 24IntelliGEN pump dispense adjustmentsDispense Shut-offShut-off too earlypressure in dispense line still highshut-off very fast droplet might be rip off the resist stream air bubbles sucked into the nozzletimeDispense rateShut-offAir sucked inShut-off too latepressure in dispense line almost“0”dispense rate gets very low and dispense splits into dropletsdroplet remaining at nozzle tiptimeDispense rateShut-offDroplet at dispense end32May 24IntelliGEN pump dispense adjustmentsDispense Shut-off adjustmentfully close the Suck-back volume adjustment before adjusting the Shut-offby using the speedcontroller“Shut-off”(closing the SC will delay the Shut-off)fully open the SCclose it in steps of 180 until Shut of is too lateopen it in steps of 45always fix the lock nut(fixing the lock nut may change the adjustment again)by using the“Suckback delay”parameter of pump recipe(“SC valve close”fully opened)set“SB-delay”to 0.10 secdecrease in steps of 0.01 secfine adjust it in steps of 0.005 secShut-off too lateShut-off too earlyShut-off best33May 24IntelliGEN pump dispense adjustmentsSuck-backopen speedcontroller“suck-back”fullyadjust 1-2 mm suck-back(SB volume ccw)and fix the lock nutwait 5 min and readjust suck-back volume(might have changed due to influence of resist temperature)close speedcontroller“suck-back”in steps of 180 until a suck-back is occurringdo not change the suck-back volume again(if SB occurs too early it occurs during dispense and is therefore not visible)fine tune the time between shut-off and suck-back to 0.5-1.0 secnever create an overlay of shut-of f and suck-backprogrammable suck-back of pump is not working(1mm in nozzle equals 0.003 cc but minimum programmable increment is 0.01cc)1-2 mmtimeDispense rate0.5-1.0 sec34May 24IntelliGEN pump dispense adjustmentsPump Feedreloads the resist into the Feed PumpFeed Time setting in the recipe is just a time frame given to the pump(longer Feed Time do not slow down the refill rate)reload rate is influence byvacuum applied to Feed Pump(pump internal control)Resist viscositytube length and diameter between reservoir and pumpPump Ventvents the Resist filtervented volume is usually sent to drain Vent is part of the Resist consumptionnecessary vent frequency and time depend onused Resist(outgasing,viscosity,content of surfactants)frequency of use(for dummy dispense vent frequency should be set to“1”)Pump Purgepurges a small amount of the Resist from the Dispense Pump back to the pump inlet(not part of the Resist consumption)air bubbles created in filter are purged out(no air bubbles can reach the dispense line)consumes capacity of Dispense Pump(7.0 cc)partially should not be larger than 1-2 cc35May 24GEN2 pump recipeGeneral settings:Pump pressure:40 kPaPump vacuum:-75 kPa 36May 24GEN2 pump adjustmentsSpeedcontroller at line#6SC valve closeResist PressureReservoirDrainGEN2 pumpResist Bottle37May 24GEN2 pump adjustmentsDispense startno adjustment since no external valve usedmultirate dispense not possibletherefore pump needs to be assembled as close as possible to the dispense nozzleall others analogue to IntelliGENDispensesame as for IntelliGEN single dispense rateno multi rate possibleDispense Shut-offclosing of“SC valve close”will delay Shut-off in the same way as at IntelliGEN pumpsince the pump is not used with an external valve the Shut-off can be adjusted too late because of the much larger distance between outlet valve and nozzleSuck-backno suck-back via external valve possibleprogrammable suck-back of pump is not working(1mm in nozzle equals 0.003 cc but minimum programmable increment is 0.01cc)38May 24IWAKI Bellows pump adjustmentsPump Preparation(IWAKI F-T100-1,IWAKI SB)Before first useprime the dispense system with solvent(original Resist thinner or major Resist solvent,never use Aceton!)purge the dispense system with app.1 litre of solvent(reduce dispense pressure if pneumatic pump is used,since viscosity of solvent is much lower than those of resist)empty the system up to the filter(take care that the reservoir is really empty,do not empty the filter since it will clog as soon as air gets in)prime the dispense system with Resistpurge the dispense system with at least 1 litre of resist(use maximum pump stroke to purge air out of the pump and the dispense line)vent the filter thoroughly39May 24IWAKI Bellows pump adjustmentsPump Preparation(IWAKI F-T100-1,IWAKI SB)Change of Resistempty the