Lead-free solder

Abstract

Lead-free solder comprising Sn, Zn and 0.001 to 0.005 wt. % Ti. The lead-free solder does not contain toxic lead, and has sufficient bonding strength to oxide materials such as glass and ceramics.

What is claimed is:  
     
         1 . Lead-free solder comprising Sn, Zn and 0.001 to 0.005 wt. % of Ti.  
     
     
         2 . Lead-free solder as claimed in  claim 1 , wherein a ratio of Sn to Zn (Sn/Zn) is 4.0 to 19.0.  
     
     
         3 . Lead-free solder as claimed in  claim 1 , wherein the ratio of Sn to Zn (Sn/Zn) is 9.0 to 12.0, and said solder contains substantially no Cu.  
     
     
         4 . Lead-free solder consisting essentially of Sn, Zn, 0.001 to 0.005 wt. % of Ti, and 0.001 to 0.005 wt. % of Al, wherein a ratio of Sn to Zn (Sn/Zn) is 4.0 to 19.0.  
     
     
         5 . Lead-free solder consisting essentially of Sn, Zn, 0.001 to 0.005 wt. % of Ti, and 0.001 to 9.0 wt. % of Cu wherein a ratio of Sn to Zn (Sn/Zn) is 4≦Sn/Zn<9 and 12<Sn/Zn≦19.  
     
     
         6 . Lead-free solder consisting essentially of Sn, Zn, 0.001 to 0.005 wt. % of Ti, 0.001 to 0.005 wt. % of Al, and 5.0 to 9.0 wt. % of Cu, wherein a ratio of Sn to Zn (Sn/Zn) is 4≦Sn/Zn<9 and 12<Sn/Zn≦19.  
     
     
         7 . Lead-free solder consisting essentially of Sn, Zn, 0.001 to 0.005 wt. % of Ti, and at least one element selected from a group consisting of Bi, Si and Sb in a range of 3.2 to 10 wt. %, wherein a ratio of Sn to Zn (Sn/Zn) is 4.0 to 19.0.