Patent ID: 6184149
Filing Date: 2001-02-06
Classification: H01L

Abstract:
(Amended) A method for monitoring self-aligned contact (SAC) etching process, said method comprising the steps of:providing a set of wafers with an oxide layer as a set of oxide control wafers;generating a data base which includes a set of depths of etching profile transition, a set of depths of etching stop, a set of SAC chamber conditions and a set of correlated SAC etching parameters;performing a SAC etching process to etch an oxide control wafer and a SAC wafer by a first gas CH.sub.3 F and a second gas, said CH.sub.3 F having a variable flow rate, wherein the flow rate variation of said CH.sub.3 F changes said depth of etching profile transition, thereby a depth of etching profile transition and a depth of etching stop are generated in said oxide control wafer and said SAC wafer; andmeasuring said depth of etching profile transition and said depth of etching stop in said oxide control wafer to monitor said chamber condition of said SAC etching process.