Multibeam System

Abstract

A multibeam system in which a charged particle beam and one or more additional beams can be directed to the target within a single vacuum chamber. A first beam colunm preferably produces a beam for rapid processing, and a second beam column produces a beam for more precise processing. A third beam column can be used to produce a beam useful for forming an image of the sample while producing little or no change in the sample.

1 . A charged-particle beam system, comprising:
 a vacuum chamber;   a workpiece support for supporting a workpiece within the vacuum chamber;   an ion beam system including an ion source for generating ions and a focusing column for forming the ions into a beam having a sub-micron diameter at the workpiece;   an electron beam system including a source for generating electrons and a focusing column for forming the electrons into a beam having a sub-micron diameter at the workpiece; and   a third beam system including a source of focused beam capable of rapid material removal, the third beam system having a resolution significantly less than that of the ion beam system and a removal rate significantly greater than that of the ion beam system;   wherein the third beam system is suitable for rapid removal of material, the ion beam system is suitable for producing a feature at a higher resolution than the third beam system, and the electron beam is suitable for forming a high resolution image of the workpiece.   
     
     
         2 . The charged particle beam system of  claim 1  in which the third beam comprises a laser. 
     
     
         3 . The charged particle beam system of  claim 2  in which the laser comprises a femtosecond laser. 
     
     
         4 . The charged particle beam system of  claim 1  in which the third beam comprises a plasma ion beam system. 
     
     
         5 . The charged particle beam system of  claim 4  in which the plasma ion beam system comprises an inductively coupled, magnetically enhanced plasma ion beam system. 
     
     
         6 . The charged particle beam system of  claim 4  in which the plasma ion beam system includes:
 an antenna in proximity to the vessel, the antenna excited by an RF electrical source to induce ionization of the plasma; 
 circuitry that couples the antenna to the electrical source to substantially reduce oscillations in the ionized plasma; and 
 an extraction mechanism to extract the ionized plasma into a beam. 
 
     
     
         7 . The charged particle beam system of  claim 1  in which:
 the ion beam system comprises a liquid metal ion beam system; 
 the electron beam system includes a secondary electron detector for imaging the workpiece; and 
 the third beam system comprises a laser. 
 
     
     
         8 . The charged particle beam system of  claim 1  in which:
 the ion beam system comprises a liquid metal ion beam system; 
 the electron beam system includes a secondary electron detector for imaging the workpiece; and 
 the third beam system comprises a plasma ion beam system. 
 
     
     
         9 . A charged-particle beam system, comprising:
 a vacuum chamber;   a workpiece support for supporting a workpiece within the vacuum chamber;   a liquid metal ion beam system including a source for generating metal ions; and a focusing column for forming the metal ions into a beam having a sub-micron diameter at the workpiece;   an electron beam system including a source for generating electrons and a focusing column for forming the electrons into a beam having a sub-micron diameter at the workpiece; and   a plasma ion system including a plasma source of ions, and a focusing column for forming the ions from the plasma ion source into a beam and directing the beam to the workpiece.   
     
     
         10 . A charged-particle beam system, comprising:
 a vacuum chamber;   a workpiece support for supporting a workpiece within the vacuum chamber;   a liquid metal ion beam system including a source for generating metal ions; and a focusing column for forming the metal ions into a beam having a sub-micron diameter at the workpiece;   a plasma ion system including a plasma source of ions, and a focusing column for forming the ions from the plasma ion source into a beam and directing the beam to the workpiece;   the ion focusing column and the plasma focusing column sharing a common optical column comprising one or more lenses for focusing either the metal ions or the plasma ions onto the workpiece.   
     
     
         11 . The charged-particle beam system of  claim 10  in which:
 the metal ion beam source is located on the same axis as the common optical column; 
 the plasma ion beam source is located off the axis of the common optical column; and 
 an electrostatic spherical sector is used to deflect the plasma beam onto the axis of the common optical column so that the metal ion beam and the plasma ion beam will be coincident on a sample. 
 
     
     
         12 . The charged-particle beam system of  claim 11  in which the electrostatic spherical sector is a stigmatic imaging, 90 degree electrostatic spherical sector. 
     
     
         13 . The charged-particle beam system of  claim 11  in which the electrostatic spherical sector is a stigmatic imaging magnetic mass filter. 
     
     
         14 . The charged-particle beam system of  claim 10  in which the common optical column has two common lenses suitable for achieving optical demagnification from 500× to 1000× for a plasma source. 
     
     
         15 . The charged-particle beam system of  claim 10  further comprising an electron beam column. 
     
     
         16 . The charged-particle beam system of  claim 15  in which the electron column also shares the common optical column and in which the common optical column includes a mixed magnetic/electrostatic lens. 
     
     
         17 . A method of processing a sample using a multibeam system, the system having a first ion column, a second ion column, and an electron beam column, with the first ion column producing an ion beam that has a greater beam current and a larger beam diameter than the ion beam produced by the second ion column, the method comprising:
 imaging the sample using the second ion beam column or the electron beam column;   directing a beam of ions using the first ion column toward the sample to rapidly remove material from the sample;   re-imaging the sample using the second ion beam column or the electron beam column after the material has been removed by the ion beam from the first ion column; and   directing a beam of ions toward the sample using the second ion column to complete the desired material removal.   
     
     
         18 . The method of  claim 17  in which the first ion column is a plasma ion column and the second ion column is a liquid metal ion column. 
     
     
         19 . The system of  claim 4  in which the plasma ion beam has a beam current greater than 100 nanoamps. 
     
     
         20 . The system of  claim 4  in which the plasma ion beam has a beam diameter of 10 nm to 50 μm. 
     
     
         21 . The system of  claim 4  in which the plasma ion beam has a beam current of 300 to 20,000 nanoamps. 
     
     
         22 . The system of  claim 4  in which the plasma ion beam has a beam current of 1500 to 5000 nanoamps. 
     
     
         23 . The system of  claim 4  in which the ion beam has a beam current less than 20 nanoamps.