As semiconductor manufacturers march to thedrum beat of Moore's Law there is very little roomfor yield maverieks, especially those that can beprevented. Critical process errors are costly andphotolithography is one of the few processes insemiconductor manufacturing where there is anopportunity to correct errors. Small changes inphotoresist-dispensed volume may have severeimpact on film thickness uniformity and can ulti-mately affect patterning It is important to monitorphoto dispense conditions to detect real-timeevents that may have a direct negative impact onprocess yield and be able to react to these eventsas quickly as possible.This paper presents an evaluation of the IntelliGen Mini, a photoresist dispense system manufacturedby Entegris, Inc. This system utilizes advancedequipment control software, known as dispenseconfirmation, to detect variations in photo dis-pense. These variations, caused by bubbles inthe dispense line, valve errors and accidentally-changed chemistries can all create maverick yieldevents that can go undetected until metrology,defeet inspection or wafer final testThe ability of an advanced dispense system todetect events and create alerts is a very powerfultool, but it can be most effective when that infor-mation is collected and analyzed by an automatedsystem. In a modern fabricator this is most likely astatistical process control chart that is monitoringa track's progress and is ready to stop the trackwhen a maverick event occurs or alert personnelto trends they may not otherwise catch with otherinline ntetrology data. Dispense confirmation,when Combined with networking capabilities,can meet this need.After a brief description of the pump, data from sim-ulated yield-affecting events will be examined toevaluate the IntelliGen Mini's ability to detect them.This discussion will eonclude with a brief analysisof the ultilnate time and cost savings of utilizingdispense confirmation with networking capabilitiesto detect and eliminate poorly-coated wafers.
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