Photomask for aberration measurement, aberration measurement method unit for aberration measurement and manufacturing method for device

Abstract

A photomask for aberration measurement of the present invention comprises a substrate that allows exposure light to pass through, a plurality of aperture patterns for measurement that are formed on the top surface of substrate in a plurality of measurement pattern formation regions, a light blocking film that is formed in the measurement pattern formation regions on the rear surface of substrate and that has a rear surface aperture pattern for substantially differentiating the respective incident angles of the exposure light to plurality of aperture patterns for measurement and a plurality of reference patterns that is formed in a single, or in a plurality, of reference pattern formation region(s) on the top surface of substrate, wherein the rear surface of substrate in the reference pattern formation region(s) is formed so that the respective incident angles of the exposure light to plurality of reference patterns becomes the substantially the same.

1 - 12 . (canceled)  
     
     
         13 . For a photomask for aberration measurement for measuring a lens aberration in a projection optical system of an exposure unit, comprising a substrate that allows an exposure light to pass through and that has a measurement pattern formation region and a reference pattern formation region, a plurality of measurement patterns formed on a top surface of said substrate in said measurement pattern formation region, a light blocking film that is formed on a rear surface of said substrate in said measurement pattern formation region and that has a rear surface aperture pattern for substantially differentiating respective incident angles of an exposure light that enters each of said plurality of measurement patterns, and a plurality of reference patterns formed on the top surface of said substrate in said reference pattern formation region, wherein the rear surface of said substrate in said reference pattern formation region is formed so that respective incident angles of an exposure light that enters said plurality of reference patterns are substantially the same; 
 an aberration measurement method, comprising the steps of:    transferring said plurality of measurement patterns of said photomask for aberration measurement to a photosensitive material;    measuring an amount of positional shift of the transferred pattern; and    calculating an inclination of the equiphase wave surface that is theoretically proportional to said amount of positional shift so as to find the wave surface aberration by using information of the calculated inclination of said equiphase wave surface.    
     
     
         14 . The aberration measurement method according to  claim 13 , characterized in that said step of measuring the amount of positional shift of said transferred pattern has the step of carrying out a second exposure subsequent to shifting said photosensitive material relative to said photomask for aberration measurement after carrying out a first exposure using said photomask for aberration measurement and, thereby, measuring the amount of mutual positional shift between the transferred pattern of said measurement pattern that is transferred to said photosensitive material through either one of the first and second exposures and the transferred pattern of said reference pattern that is transferred to said photosensitive material through the other of the first and second exposures.  
     
     
         15 . The aberration measurement method according to  claim 13 , characterized in that said step of measuring the amount of positional shift of said transferred pattern has the step of using a coordinate measurement unit so as to measure the amount of positional shift of said transferred pattern relative to the reference provided in said coordinate measurement unit.  
     
     
         16 . The aberration measurement method according to  claim 15 , characterized in that said coordinate measurement unit is a projection exposure unit.  
     
     
         17 . The aberration measurement method according to  claim 14 , characterized in that either one of the transferred pattern of said measurement pattern and the transferred pattern of said reference pattern is an inner box pattern of a box-in-box type mark while the other of the transferred pattern of said measurement pattern and the transferred pattern of said reference pattern is an outer box pattern and the amount of positional shift between said inner box pattern and said outer box pattern is measured by an overlap inspection unit.  
     
     
         18 . The aberration measurement method according to  claim 13 , further comprising the steps of measuring the phase distribution within the iris for each focus when said plurality of measurement patterns is transferred to a photosensitive material by changing the focus, of calculating said phase distribution within the iris at the time of defocusing according to the standard of said phase distribution within the iris for the optimal focus and of specifying the center position of the iris as the center of a paraboloid of revolution that represents a change in said phase distribution within the iris at said time of defocusing.  
     
     
         19 . (canceled)  
     
     
         20 . A manufacturing method for a device, characterized in that an aberration measurement method according to  claim 13  is used.