Filling materials and methods of filling through holes of a substrate

Abstract

Pastes are disclosed that are configured to coat a passage of a substrate. When the paste is sintered, the paste becomes electrically conductive so as to transmit electrical signals from a first end of the passage to ta second end of the passage that is opposite the first end of the passage. The metallized paste contains a lead-free glass frit, and has a coefficient of thermal expansion sufficiently matched to the substrate so as to avoid cracking of the sintered paste, the substrate, or both, during sintering.

What is claimed: 
     
         1 . A glass substrate defining first and second external surfaces, the substrate comprising:
 a passage that extends from the first external surface to the second external surface, wherein the passage is defined by at least one side wall of the glass substrate;   a lead-free electrically conductive material that extends along an entirety of the passage and is bonded to the at least one side wall; and   a lead-free glass frit disposed in the passage.   
     
     
         2 . The glass substrate of  claim 1 , wherein the lead-free electrically conductive material comprises a metal. 
     
     
         3 . The glass substrate of  claim 2 , wherein the metal comprises silver or an oxide or alloy thereof, copper or an oxide or alloy thereof, or gold or an oxide or alloy thereof. 
     
     
         4 . The glass substrate of  claim 1 , wherein the passage is a through-passage. 
     
     
         5 . The glass substrate of  claim 4 , wherein the passage has a maximum cross-sectional dimension that is in a range from about 5 microns to about 3000 microns. 
     
     
         6 . The glass substrate of  claim 4 , comprising quartz. 
     
     
         7 . The glass substrate of  claim 5 , wherein the first and second external surfaces are opposite each other. 
     
     
         8 . A glass substrate defining first and second external surfaces, the substrate comprising:
 a hole that extends from the first external surface to the second external surface, wherein the hole is defined by at least one side wall of the glass substrate;   a lead-free metal plated in the hole; and   an electrically nonconductive polymer disposed in the hole.   
     
     
         9 . The glass substrate of  claim 8 , wherein the passage has a maximum cross-sectional dimension that is in a range from about 5 microns to about 3000 microns. 
     
     
         10 . The glass substrate of  claim 8 , wherein the lead-free metal extends along an entirety of the at least one side wall. 
     
     
         11 . The glass substrate of  claim 10 , comprising quartz. 
     
     
         12 . A glass substrate defining first and second external surfaces, the substrate comprising:
 a hole that extends from the first external surface to the second external surface, wherein the hole is defined by at least one side wall of the glass substrate;   a lead-free electrically conductive material that is plated in the hole, such that the hole defines a remaining space; and   a lead-free electrically conductive polymer that fills the remaining space of the hole.   
     
     
         13 . The glass substrate of  claim 12 , wherein the lead-free electrically conductive material comprises gold, copper, or silver. 
     
     
         14 . The glass substrate of  claim 12 , wherein the electrically conductive polymer comprises at least one of copper, silver, or gold. 
     
     
         15 . The glass substrate of  claim 14 , wherein the lead-free electrically conductive material extends from the first external surface to the second external surface.