Exposure method

Abstract

An exposure method for exposing a pattern of a reticle onto a plate using a light from a light source and an optical system includes the steps of obtaining a relationship between an exposure parameter that determines a mode to expose a plate, and an electrical characteristic of a device derived from the device, determining whether the device obtained from the set exposure parameter has a predetermined electrical characteristic, and adjusting the set exposure parameter based on the relationship between the exposure parameter and the electrical characteristic, if the determining step determines that the device does not have the predetermined electrical characteristic.

1 . An exposure method for exposing a pattern of a reticle onto a plate using a light from a light source and an optical system, said exposure method comprising the steps of: 
 obtaining a relationship between an exposure parameter that determines a mode to expose a plate, and an electrical characteristic of a device derived from the device;    determining whether the device obtained from the set exposure parameter has a predetermined electrical characteristic; and    adjusting the set exposure parameter based on the relationship between the exposure parameter and the electrical characteristic, if said determining step determines that the device does not have the predetermined electrical characteristic.    
     
     
         2 . An exposure method according to  claim 1 , wherein the exposure parameter includes a numerical aperture of a projection optical system for projecting the pattern onto the plate, and an effective light source shape of the light for illuminating the reticle.  
     
     
         3 . An exposure method according to  claim 1 , wherein when plural exposure parameters influence the predetermined exposure parameter, said adjusting step selects the most influential exposure parameter on the predetermined electrical characteristic among the plural exposure parameters.  
     
     
         4 . An exposure method according to  claim 1 , wherein said adjusting step selects one of plural diffraction optical elements in the optical system.  
     
     
         5 . An exposure method according to  claim 1 , wherein when there are plural electrical characteristics, said determining step selects the most influential electrical characteristic on a yield rate of the device among the plural electrical characteristics.  
     
     
         6 . An exposure method according to  claim 1 , wherein when plural exposure parameters relates as a function to the predetermined exposure parameter, said adjusting step selects one of the plural exposure parameters, which one has the largest value when the set exposure parameter is substituted for a differential function of the function.  
     
     
         7 . An exposure method according to  claim 1 , wherein said adjusting step includes the steps of: 
 adjusting a first exposure parameter that depends upon the optical system, by using an optical simulation; and    adjusting a second exposure parameter that does not depend upon the optical system, without an optical simulation.    
     
     
         8 . A database that stores a relationship used for an exposure method according to  claim 1 .  
     
     
         9 . A program for enabling a computer to implement an exposure method according to  claim 1.