Exposure apparatus, exposure method, and method for producing device

Abstract

In an exposure apparatus, an exposure of a substrate (P) is carried out by filling at least a portion of the space between a projection optical system (PL) and the substrate (P) with a liquid ( 50 ) and projecting the image of a pattern onto the substrate (P) via the projection optical system (PL). An optical element ( 60 ) and a barrel (PK), which are in contact with the liquid ( 50 ) when the substrate (P) is moved, are surface-treated for adjusting the affinity with the liquid ( 50 ). Consequently, generation of bubbles in the liquid between the projection optical system and the substrate is suppressed and the liquid is always retained between the projection optical system and the substrate, thereby creating a good immersion state.

1 . An exposure apparatus which exposes a substrate by transferring an image of a pattern through a liquid onto the substrate, the exposure apparatus comprising: 
 a projection optical system which projects the image of the pattern onto the substrate, wherein:    a portion of the projection optical system, which makes contact with the liquid, is surface-treated to adjust affinity for the liquid.    
   
   
       2 . The exposure apparatus according to  claim 1 , wherein the substrate is exposed while being moved in a scanning direction.  
   
   
       3 . The exposure apparatus according to  claim 1 , wherein the surface treatment is performed depending on polarity of the liquid.  
   
   
       4 . The exposure apparatus according to  claim 3 , wherein the liquid is water, and the surface treatment is applied to the portion to make contact with the liquid by forming a thin film with a substance having a molecular structure of large polarity.  
   
   
       5 . The exposure apparatus according to  claim 3 , wherein the liquid is fluorine-based liquid, and the surface treatment is applied to the portion to make contact with the liquid by forming a thin film with a substance having a molecular structure of small polarity.  
   
   
       6 . The exposure apparatus according to  claim 1 , wherein the portion of the projection optical system to make contact with the liquid includes a surface of an optical element disposed at a tip of the projection optical system and at least a part of a surface of a holding member which holds the optical element, and the surface of the optical element and at least the part of the surface of the holding member are surface-treated so that affinity for the liquid is increased.  
   
   
       7 . The exposure apparatus according to  claim 1 , wherein at least a part of the portion of the projection optical system to make contact with the liquid, through which an exposure light beam passes, is surface-treated so that affinity for the liquid is increased.  
   
   
       8 . An exposure apparatus which exposes a substrate by transferring an image of a pattern through a liquid onto the substrate, the exposure apparatus comprising: 
 a projection optical system which projects the image of the pattern onto the substrate, wherein:    the projection optical system has a first surface area which includes a surface of an optical element disposed at a tip of the projection optical system, and a second surface area which is disposed around the first surface area; and    affinity of the first surface area for the liquid is higher than affinity of the second surface area for the liquid.    
   
   
       9 . The exposure apparatus according to  claim 8 , wherein the liquid is retained in the first surface area owing to the affinity of the first surface area for the liquid which is higher than the affinity of the second surface area for the liquid.  
   
   
       10 . The exposure apparatus according to  claim 1 , wherein a conditional expression (v·d·ρ)/μ≦2,000 is satisfied provided that d represents a thickness of the liquid between the projection optical system and the substrate, v represents a velocity of a flow of the liquid between the projection optical system and the substrate, ρ represents a density of the liquid, and μ represents a coefficient of viscosity of the liquid.  
   
   
       11 . The exposure apparatus according to  claim 8 , wherein a conditional expression (v·d·ρ)/μ≦2,000 is satisfied provided that d represents a thickness of the liquid between the projection optical system and the substrate, v represents a velocity of a flow of the liquid between the projection optical system and the substrate, ρ represents a density of the liquid, and μ represents a coefficient of viscosity of the liquid.  
   
   
       12 . The exposure apparatus according to  claim 1 , further comprising a liquid immersion unit which makes the liquid to flow through at least a part of a space between the projection optical system and the substrate, wherein the liquid flows as a laminar flow.  
   
   
       13 . The exposure apparatus according to  claim 8 , further comprising a liquid immersion unit which makes the liquid to flow through at least a part of a space between the projection optical system and the substrate, wherein the liquid flows as a laminar flow.  
   
   
       14 . An exposure apparatus which exposes a substrate by illuminating a pattern with an exposure beam and transferring an image of the pattern through a liquid onto the substrate, the exposure apparatus comprising: 
 a projection optical system which projects the image of the pattern onto the substrate; and    a liquid immersion unit which fills, with the liquid, at least a part of a space between the projection optical system and the substrate, wherein:    a conditional expression (v·d·ρ)/μ≦2,000 is satisfied provided that d represents a thickness of the liquid, v represents a velocity of a flow of the liquid between the projection optical system and the substrate, ρ represents a density of the liquid, and μ represents a coefficient of viscosity of the liquid.    
   
   
       15 . The exposure apparatus according to  claim 14 , further comprising a supply unit which supplies the liquid to the space between the projection optical system and the substrate, and a recovery unit which recovers the liquid from the space between the projection optical system and the substrate, wherein an amount of the liquid to be supplied by the supply unit and an amount of the liquid to be recovered by the recovery unit are determined so that the conditional expression is satisfied.  
   
   
       16 . The exposure apparatus according to  claim 15 , wherein the substrate is scanning-exposed while being moved in a scanning direction, and a velocity of movement of the substrate during the scanning exposure is determined so that the conditional expression is satisfied.  
   
   
       17 . The exposure apparatus according to  claim 14 , wherein the substrate is scanning-exposed while being moved in a scanning direction, and a velocity of movement of the substrate during the scanning exposure is determined so that the conditional expression is satisfied.  
   
   
       18 . The exposure apparatus according to  claim 16 , wherein a direction, in which the liquid flows, is parallel to the scanning direction.  
   
   
       19 . The exposure apparatus according to  claim 14 , wherein the space between the projection optical system and the substrate is filled with the liquid, and the thickness d of the liquid is a spacing distance between the projection optical system and the substrate.  
   
   
       20 . The exposure apparatus according to  claim 14 , wherein a cover glass is placed over the substrate during the exposure, and the thickness d of the liquid is a spacing distance between the projection optical system and the cover glass.  
   
   
       21 . An exposure apparatus which exposes a substrate by illuminating a pattern of a mask with an exposure beam and transferring an image of the pattern through a liquid onto the substrate, the exposure apparatus comprising: 
 a projection optical system which projects the image of the pattern onto the substrate; and    a liquid immersion unit which fills, with the liquid, at least a part of a space between the projection optical system and the substrate, wherein:    the liquid flows as a laminar flow in parallel to a scanning direction of the substrate.    
   
   
       22 . The exposure apparatus according to  claim 21 , wherein a velocity of movement of the substrate in the scanning direction during the exposure for the substrate is determined so that the liquid flows as the laminar flow.  
   
   
       23 . The exposure apparatus according to  claim 22 , wherein the liquid immersion unit has a supply unit which supplies the liquid and a recovery unit which recovers the liquid.  
   
   
       24 . The exposure apparatus according to  claim 23 , further comprising a control unit which controls an amount of the liquid to be supplied by the supply unit and an amount of the liquid to be recovered by the recovery unit so that the liquid flows as the laminar flow.  
   
   
       25 . The exposure apparatus according to  claim 21 , wherein the liquid immersion unit has a supply unit which supplies the liquid and a recovery unit which recovers the liquid, and the exposure apparatus further comprises a control unit which controls an amount of the liquid supplied by the supply unit and an amount of the liquid recovered by the recovery unit so that the liquid flows as the laminar flow.  
   
   
       26 . The exposure apparatus according to  claim 14 , wherein the liquid is water.  
   
   
       27 . The exposure apparatus according to  claim 21 , wherein the liquid is water.  
   
   
       28 . The exposure apparatus according to  claim 14 , wherein the liquid is fluorine-based liquid.  
   
   
       29 . The exposure apparatus according to  claim 21 , wherein the liquid is fluorine-based liquid.  
   
   
       30 . The exposure apparatus according to  claim 21 , wherein the liquid immersion unit has a supply unit which supplies the liquid and a recovery unit which recovers the liquid, and the supply unit includes a nozzle which has a slit or a porous member provided for the nozzle.  
   
   
       31 . An exposure apparatus which exposes a substrate by illuminating a pattern with an exposure beam and transferring an image of the pattern through a liquid onto the substrate, the exposure apparatus comprising: 
 a projection optical system which projects the image of the pattern onto the substrate;    a liquid immersion unit which supplies the liquid onto only the substrate; and    a control unit which controls the liquid immersion unit, wherein:    the control unit controls the liquid immersion unit so that the supply of the liquid is stopped during the exposure of the substrate.    
   
   
       32 . The exposure apparatus according to  claim 31 , wherein a thickness of the liquid supplied onto the substrate is thinner than a working distance of the projection optical system, and the liquid is retained by surface tension on the substrate.  
   
   
       33 . A method for producing a device, comprising using the exposure apparatus as defined in  claim 1 .  
   
   
       34 . A method for producing a device, comprising using the exposure apparatus as defined in  claim 8 .  
   
   
       35 . A method for producing a device, comprising using the exposure apparatus as defined in  claim 14 .  
   
   
       36 . A method for producing a device, comprising using the exposure apparatus as defined in  claim 21 .  
   
   
       37 . A method for producing a device, comprising using the exposure apparatus as defined in  claim 31 .  
   
   
       38 . An exposure method for exposing a substrate by projecting an image of a pattern onto the substrate by using a projection optical system, the exposure method comprising: 
 applying a surface treatment to a surface of the substrate before the exposure in order to adjust affinity for the liquid;    filling at least a part of a space between the projection optical system and the substrate with the liquid; and    projecting the image of the pattern onto the substrate through the liquid.    
   
   
       39 . The exposure method according to  claim 38 , wherein the exposure is performed for the substrate while moving the substrate in a scanning direction.  
   
   
       40 . The exposure method according to  claim 38 , wherein the surface treatment is performed depending on polarity of the liquid.  
   
   
       41 . The exposure method according to  claim 40 , wherein the liquid is water, and a thin film is formed with a substance having a molecular structure of large polarity on a portion which makes contact with the liquid.  
   
   
       42 . The exposure method according to  claim 40 , wherein the liquid is fluorine-based liquid, and a thin film is formed with a substance having a molecular structure of small polarity on a portion which makes contact with the liquid.  
   
   
       43 . A method for producing a device, comprising using the exposure method as defined in  claim 38  to produce the device.