Illumination optical system, exposure method and designing method

Abstract

Exposure for performing patterning in which micropatterns differing in pitch exist in close vicinity to one another is handled, and micropatterns are formed with high accuracy with sufficient manufacture process margins without using a photomask complicated in manufacturing process at high manufacture cost like an alternating phase shift mask. A light intensity distribution of irradiation light constituted of double pole illuminations is formed to correspond to L&S patterns. The double pole illumination is constituted of a pair of illumination modes, and the double pole illumination is constituted of a pair of illumination modes.

1 . An illumination optical system, comprising:
 a light source which generates irradiation light;
 a condensing optical system which condenses the irradiation light; and 
 an illumination control mechanism which controls the irradiation light passing through said condensing optical system to irradiate it to an irradiation object, 
 wherein said illumination control mechanism adjusts a light intensity distribution of the irradiation light to be irradiated to the irradiation object to be in an illumination state in which a plurality of double pole illuminations or a plurality of quadrupole illuminations are combined at positions differing from each other. 
   
     
     
         2 . The illumination optical system according to  claim 1 , wherein the illumination state is formed by adjusting sizes of a pair of illumination modes constituting the illumination state for each of the illumination state. 
     
     
         3 . The illumination optical system according to  claim 1 , wherein the illumination state is formed by adjusting positions of a pair of illumination modes constituting the illumination state to be shifted inward or outward from a reference position of the illumination state for each of the double pole illuminations. 
     
     
         4 . The illumination optical system according to  claim 1 , wherein the illumination state is formed by adjusting shapes of a pair of illumination modes constituting the illumination state for each of the illumination state. 
     
     
         5 . An aligner which exposes and transfers a mask pattern of a photomask that is the irradiation object to a transfer object, comprising:
 an illumination optical system, comprising:
 a light source which generates irradiation light; 
 a condensing optical system which condenses the irradiation light; and 
 an illumination control mechanism which controls the irradiation light passing through said condensing optical system to irradiate it to an irradiation object, 
 wherein said illumination control mechanism adjusts a light intensity distribution of the irradiation light to be irradiated to the irradiation object to be in an illumination state in which a plurality of double pole illuminations or a plurality of quadrupole illuminations are combined at positions differing from each other; and 
 a project optical system which condenses the irradiation light passing through the mask pattern of the photomask to the transfer object. 
   
     
     
         6 . The aligner according to  claim 5 , wherein said illumination optical system constitutes a polarized illumination system having a function of the double pole illumination or the quadrupole illumination. 
     
     
         7 . A method for controlling illumination, comprising:
 when controlling irradiation light and irradiating it to an irradiation object,   adjusting a light intensity distribution of the irradiation light which is irradiated to the irradiation object to be in an illumination state in which a plurality of double pole illuminations or a plurality of quadrupole illuminations are combined at positions differing from each other.   
     
     
         8 . The method for controlling illumination according to  claim 7 , wherein the illumination state is formed by adjusting sizes of a pair of illumination modes constituting the illumination state for each of the illumination state. 
     
     
         9 . The method for controlling illumination according to  claim 7 , wherein the illumination state is formed by adjusting positions of a pair of illumination modes constituting the illumination state to be shifted inward or outward from a reference position of the illumination state for each of the double pole illuminations. 
     
     
         10 . The method for controlling illumination according to  claim 7 , wherein the illumination state is formed by adjusting shapes of a pair of illumination modes constituting the illumination state for each of the illumination state.