Composite material comprising silicon matrix and method of producing the same

Abstract

Proposed are a composite material, wherein non-penetrating pores that are formed in a silicon surface layer are filled up with a metal or the like without leaving any voids by using the plating technique, and a method of producing the composite material. A composite material, which has been packed at a high accuracy, or in other words, in which little voids are left, can be obtained by filling up non-penetrating pores that are formed from a silicon surface ( 100 ) substantially with a second metal or an alloy of the second metal ( 106 ) with the use of the autocatalytic electroless plating technique wherein a first metal located at the bottom of the non-penetrating pores as described above serves as the starting point.

1 . A method of producing a composite material comprising a silicon matrix, the method comprising:
 a dispersion/allocation step of dispersing and allocating on a silicon surface a first metal into shapes of particles, islands, or films;   a non-penetrating pore formation step of forming non-penetrating pores in the silicon surface by immersing the silicon surface in a second solution including fluoride ions; and   a filling step of filling up the non-penetrating pores substantially with a second metal or an alloy of the second metal by autocatalytic electroless plating, by immersing in a third solution including ions of the second metal and a reducing agent, wherein the first metal is located at bottoms of the non-penetrating pores and serves as starting points.   
     
     
         2 . A method of producing a composite material comprising a silicon matrix, the method comprising:
 a dispersion/allocation step of dispersing and allocating on a silicon surface a first metal into shapes of particles, islands, or films by immersing the silicon surface in a first solution comprising ions of the first metal and fluoride ions;   a non-penetrating pore formation step of forming non-penetrating pores in the silicon surface by immersing the silicon surface in a second solution comprising fluoride ions; and   a filling step of filling up the non-penetrating pores substantially with a second metal or an alloy of the second metal by autocatalytic electroless plating, by immersing in a third solution comprising ions of the second metal and a reducing agent, wherein the first metal is located at bottoms of the non-penetrating pores and serves as starting points.   
     
     
         3 . The method of  claim 1  or  2 , wherein:
 the silicon surface is porous by provision of the non-penetrating pores. 
 
     
     
         4 . The method of  claim 1  or  2 , wherein:
 the first metal comprises at least one metal selected from the group consisting of palladium (Pd), silver (Ag), gold (Au), platinum (Pt), and rhodium (Rh). 
 
     
     
         5 . The method of  claim 1  or  2 , wherein:
 the first metal is silver (Ag) or gold (Au), and the second metal is cobalt (Co).