Patent Number: 
Section: claims

1. A method of operation of a measurement system comprising:providing a specimen having a film;controlling a beam generator to direct a charged particle beam into the specimen;detecting a reference signal emitted from the specimen;normalizing the reference signal to create a film L-ratio; anddetermining a thickness of the film by correlating the film L-ratio to a calibration curve. 2. The method as claimed in claim 1 wherein normalizing the reference signal includes analyzing the reference signal with a calculation module for forming a detection spectrum. 3. The method as claimed in claim 1 wherein normalizing the reference signal includes analyzing the reference signal to identify a film peak and dividing the film peak by a film-only peak for identifying a film K-prime ratio. 4. The method as claimed in claim 1 wherein normalizing the reference signal includes creating the film L-ratio by dividing a film K-prime ratio by a sum of the film K-prime ratio and a substrate K-prime ratio. 5. The method as claimed in claim 1 wherein detecting the reference signal includes detecting a film signal, a substrate signal, or a combination thereof. 6. A method of operation of a measurement system comprising:providing a specimen having a film with a pattern;controlling a beam generator to direct a charged particle beam into the specimen;detecting a reference signal emitted from the specimen;normalizing the reference signal to create a film L-ratio; anddetermining a thickness of the film by correlating the film L-ratio to a calibration curve. 7. The method as claimed in claim 6 wherein controlling the beam generator includes directing the charged particle beam into the pattern having a complex geometry. 8. The method as claimed in claim 6 wherein providing the specimen includes providing the specimen having a zero edge exclusion requirement. 9. The method as claimed in claim 6 wherein controlling the beam generator to direct the charged particle beam includes directing an electron beam. 10. The method as claimed in claim 6 wherein detecting the reference signal includes detecting the reference signal in a range of 102 electron volts to 105 electron volts. 11. A measurement system comprising:a control module for providing a specimen having a film;a beam generator, coupled to the control module, for directing a charged particle beam into the specimen;a detector, coupled to the beam generator, for detecting an reference signal emitted from the specimen; andan analysis unit, coupled to the detector, for normalizing the reference signal to create a film L-ratio and determining a thickness of the film by correlating the film L-ratio to a calibration curve. 12. The system as claimed in claim 11 wherein the analysis unit is for analyzing the reference signal with a calculation module for forming a detection spectrum. 13. The system as claimed in claim 11 wherein the analysis unit is for analyzing the reference signal to identify a film peak and dividing the film peak by a film-only peak for identifying a film K-prime ratio. 14. The system as claimed in claim 11 wherein the analysis unit is for creating the film L-ratio by dividing a film K-prime ratio by a sum of the film K-prime ratio and a substrate K-prime ratio. 15. The system as claimed in claim 11 wherein the detector is for detecting a film signal, a substrate signal, or a combination thereof. 16. The system as claimed in claim 11 wherein the control module is for providing the specimen having the film with a pattern. 17. The system as claimed in claim 16 wherein the beam generator is for directing the charged particle beam into the pattern having a complex geometry. 18. The system as claimed in claim 16 wherein the control module is for providing the specimen having a zero edge exclusion requirement. 19. The system as claimed in claim 16 wherein the beam generator is for directing an electron beam. 20. The system as claimed in claim 16 wherein the detector is for detecting the reference signal in a range of 102 electron volts to 105 electron volts.