Phillip Walsh, George Li, & A. Forouhi, n&k Technology, Inc.

ABSTRACT

We present a method based on broadband spectrophotometry in conjunction with Forouhi-Bloomer dispersion equations and hybridrigorous coupled wave analysis (RCWA) for monitoring film thickness, film optical properties, trench parameters, and phase shift in phase-shift masks. The method, known as the n&k method, has certain advantages over conventional metrology in terms of throughput and suitability for integration into the mask creation process. At the same time, the n&k method has demonstrated excellent correlation with conventional metrology methods.