Patent ID: 6027837
Filing Date: 2000-02-22
Classification: G03F

Abstract:
A method for tuning the phase shifting of an attenuating phase shift mask having an attenuating phase shifting material providing at least 160.degree. of phase shifting, said method comprising the steps of:(a) forming line segment images in an attenuating phase shifting material, said attenuating phase shifting material being located on an area of a transparent or semi-transparent substrate;(b) measuring the actual phase shift provided by the imaged phase shifting material; and(c) etching said transparent or semi-transparent substrate in areas not covered by said imaged phase shifting material by an amount to tune said phase shifting of said attenuating chase shift mask to about 180.degree.; or(c') etching said imaged phase shifting material by an amount to tune said phase shifting of said attenuating phase shift mask to about 180.degree..