Efficient EUV collector designs

Abstract

A collector that includes a laser produced plasma (LPP) extreme ultra violet (EUV) light source and a first optical path from the source to a mirror. The mirror is the first mirror that light emitted from the source and traveling along the first optical path impinges upon. The collector also includes a second optical path from the source to another mirror. The other mirror is the first mirror that light emitted from the source and raveling along the second path impinges upon. The mirror and the other mirror are oriented relative to the source such that light from the source traveling along the first optical path travels in a direction opposite to light traveling from the source along the second optical path. A collector having a discharge extreme ultra violet (EUV) light source.

1 - 52 . (canceled) 
   
   
       53 . A collector comprising:
 a laser produced plasma (LPP) extreme ultra violet (EUV) light source;   a first optical path from said source to a mirror, said mirror being the first mirror that light emitted from said source and traveling along said first optical path impinges upon; and   a second optical path from said source to another mirror, said another mirror being the first mirror that light emitted from said source and traveling along said second path impinges upon, said mirror and said another mirror oriented relative to said source such that light from said source traveling along said first optical path travels in a direction opposite to light traveling from said source along said second optical path.   
   
   
       54 . The collector of  claim 53 , wherein said mirror is further positioned to reflect light traveling along said first optical path to said another mirror. 
   
   
       55 . The collector of  claim 54 , further comprising a third mirror positioned to receive light reflected from said another mirror that traveled along said first and second paths. 
   
   
       56 . The collector of  claim 55 , wherein said first mirror is faceted. 
   
   
       57 . The collector of  claim 55 , wherein said another mirror is faceted. 
   
   
       58 . The collector of  claim 55 , wherein the reflecting surface of said mirror is spherical or approximately spherical and the reflecting surface of said another mirror is elliptical or approximately elliptical. 
   
   
       59 . The collector of  claim 55 , wherein the collection angle of at least one of the mirrors is between 45° to 90° inclusive. 
   
   
       60 . The collector of  claim 54 , wherein the reflecting surface of said mirror is spherical and the reflecting surface of said another mirror is elliptical. 
   
   
       61 . The collector of  claim 54 , wherein the collection angle of at least one of the mirrors is between 25° to 90° inclusive. 
   
   
       62 . The collector of  claim 53 , wherein said mirror is smaller than said another mirror. 
   
   
       63 . The collector of  claim 53 , wherein said collector is positioned to emit light into an illumination system, said illumination system to form a light beam from a plurality of light beams. 
   
   
       64 . The collector of  claim 63 , wherein said illumination system is positioned to emit said light beam into a projection camera. 
   
   
       65 . The collector of  claim 64 , wherein at least one of said mirrors is faceted and said illumination system comprises only one mirror. 
   
   
       66 . The collector of  claim 53 , wherein said collector forms a plurality of beams with one or more of said mirrors being faceted so as to form opposite versions of said source image, said opposite versions positioned to compensate for any movement of said source. 
   
   
       67 . A collector comprising:
 a laser produced plasma (LPP) extreme ultra violet (EUV) light source;   a mirror being the first mirror that light emitted from said source and traveling to said mirror impinges upon; and   a second mirror positioned to receive light from said mirror at an angle of incidence less than or equal to 15° when measured against the reflecting surface of said second mirror.   
   
   
       68 . The collector of  claim 67 , further comprising a third mirror being the first mirror that light emitted from said source and traveling to said third mirror impinges upon. 
   
   
       69 . The collector of  claim 67 , wherein said mirror is faceted, and wherein the collection angle of said mirror is between 45° to 90° inclusive. 
   
   
       70 . A method comprising:
 emitting light from a laser produced plasma (LPP) extreme ultra violet (EUV) light source;   reflecting said light from a mirror into a second mirror, said mirror being the first mirror that said light mirror impinges upon after being emitted from said light source; and   receiving said light at said second mirror at an angle of incidence less than or equal to 15° when measured against the reflecting surface of said second mirror.   
   
   
       71 . The method of  claim 70 , further comprising:
 emitting other light from said laser produced plasma (LPP) extreme ultra violet (EUV) light source;   reflecting said other light from a third mirror to said mirror, said third mirror being the first mirror that said other light mirror impinges upon after being emitted from said light source.   
   
   
       72 . The method of  claim 70 , wherein said reflecting further comprises breaking said light down into individual beams as a consequence of said mirror being faceted. 
   
   
       73 . The method of  claim 70 , further comprising receiving said light at said mirror over a collection angle at a collection range between 45° to 90° inclusive.