Liquid tamped targets for extreme ultraviolet lithography

Abstract

An EUV light source including a vacuum chamber, a droplets injector operatively connected to the vacuum chamber for directing the droplets into the vacuum chamber, droplets produced by the droplets injector wherein the droplets have one side and another side opposite the one side, the droplets including a solid higher Z bead in a low Z liquid, and at least one laser beam directed onto the one side of the droplets.

What is claimed is: 
     
         1 - 22 . (canceled) 
     
     
         23 . An EUV light source, including:
 a vacuum chamber;   a droplets injector, operatively connected to the vacuum chamber for directing droplets into the vacuum chamber, wherein each droplet out of the droplets has one side and another side opposite the one side;   at least one laser, collectively operable to produce at least one laser beam directed onto the one side of a droplet and at least one other laser beam directed onto the other side of the droplet, thereby turning at least part of the droplet into plasma that emits EUV light.   
     
     
         24 . The EUV light source of  claim 23 , wherein the at least one laser beam includes a laser beam which is directed to hit the droplet at an angle from the plane perpendicular to the droplet injection direction. 
     
     
         25 . The EUV light source of  claim 23 , wherein the at least one laser includes a plurality of lasers, wherein at least one laser of the plurality of lasers is operable to produce a laser beam directed onto the one side of the droplet, and at least one other laser of the plurality of laser is operable to produce another laser beam directed onto the other side of the droplet. 
     
     
         26 . The EUV light source of  claim 23 , wherein the at least one laser includes a single laser operable to emit a laser beam which is split into multiple laser beams of which at least one laser beam is directed onto the one side of the droplet and at least one other laser beam is directed onto the other side of the droplet. 
     
     
         27 . The EUV light source of  claim 23 , wherein the at least one laser is collectively operable to concurrently produce: (a) the at least one laser beam directed onto the one side of a droplet, and (b) at least one other laser beam directed onto the other side of the droplet, thereby turning at least part of the droplet into plasma that emits EUV light. 
     
     
         28 . The EUV light source of  claim 23 , wherein the at least one laser is collectively operable to produce a plurality of laser beams directed onto the one side of the droplet from different angles. 
     
     
         29 . The EUV light source of  claim 28 , wherein the at least one laser includes multiple lasers, each operable to produce a laser beam out of the plurality of laser beams. 
     
     
         30 . EUV light source of  claim 28 , wherein the at least one laser includes a single laser operable to emit a laser beam which is split into multiple laser beams out of the plurality of laser beams. 
     
     
         31 . The EUV light source of  claim 28 , wherein the at least one laser is collectively further operable to produce another plurality of laser beams directed onto the other side of the droplet from different angles. 
     
     
         32 . The EUV light source of  claim 29 , wherein the at least one laser includes multiple additional lasers, each operable to produce a laser beam directed onto the other side of the droplet. 
     
     
         33 . The EUV light source of  claim 32 , wherein multiple lasers and the multiple additional lasers are collectively operable to concurrently produce: (a) multiple laser beams directed onto the one side of a droplet, and (b) multiple laser beams directed onto the other side of the droplet, thereby turning at least part of the droplet into plasma that emits EUV light. 
     
     
         34 . The EUV light source of  claim 30 , wherein the at least one laser includes another single laser operable to emit another laser beam which is split into multiple other laser beams directed onto the other side of the droplet. 
     
     
         35 . The EUV light source of  claim 31 , wherein the at least one laser includes multiple lasers arranged on the one side of the droplet directed to hit the droplet at multiple different angles from the plane perpendicular to the droplet injection direction, and multiple other lasers arranged on the other side of the droplet directed to hit the droplet at multiple different angles from the plane perpendicular to the droplet injection direction. 
     
     
         36 . The EUV light source of  claim 28 , wherein the at least one laser is operable to produce at least four laser beams directed to symmetrically hit the droplet from different angles on the one side. 
     
     
         37 . The EUV light source of  claim 23 , wherein the at least one laser is collectively operable to hit the droplet from both the one side and the other side, thereby ionizing both the one side of the droplet and the other side of the droplet. 
     
     
         38 . A method of producing EUV light, the method including the steps of:
 directing a plurality of droplets into a vacuum chamber, wherein each droplet out of the plurality of droplets has one side and another side opposite the one side; and   for each droplet out of the plurality of droplets:
 producing multiple laser beams; 
 directing at least one laser beam out of the multiple laser beams onto the one side of the respective droplet; 
 directing at least one other laser beam out of the multiple laser beams onto the other side of the respective droplet; and 
 ionizing by the at least one laser beam and the at least one other laser beam at least part of the droplet into plasma that emits EUV light. 
   
     
     
         39 . The method of  claim 38 , wherein the ionizing includes ionizing by the at least one laser beam the one side of the droplet into plasma that emits EUV light and ionizing by the at least one other laser beam the other side of the droplet into plasma that emits EUV light. 
     
     
         40 . The method of  claim 38 , comprising directing a laser beam out of the at least one laser beams to hit the droplet at an angle from the plane perpendicular to the droplet injection direction. 
     
     
         41 . The method of  claim 38 , including producing the at least one laser beam and the at least one other laser beam by different lasers. 
     
     
         42 . The method of  claim 38 , including splitting a laser beam into multiple split laser beams, directing at least one of the split laser beams onto the one side of the respective droplet and at least one other split laser beam onto the other side of the respective droplet. 
     
     
         43 . The method of  claim 38 , including producing and directing multiple laser beams to concurrently hit the respective droplet from the one side and from the other side, thereby, turning at least part of the droplet into plasma that emits EUV light. 
     
     
         44 . The method of  claim 38 , including concurrently directing a plurality of laser beams onto the one side of the respective droplet. 
     
     
         45 . The method of  claim 38 , including concurrently directing a first plurality of laser beams onto the one side of the respective droplet and a second plurality of laser beams onto the other side of the respective droplet.