Composition for bonding

1. A composition for bonding consisting of tin, iridium, germanium, nickel, optionally zinc, optionally oxygen, and an unavoidable component,

wherein a contained amount of iridium is greater than or equal to 0.0005 mass % and less than or equal to 0.1 mass %;

wherein a contained amount of germanium is less than or equal to 10 mass %,

wherein a contained amount of nickel in mass % is greater than or equal to 0.1 mass % and less than or equal to a product of 2.8 multiplied by a term that is the contained amount of germanium in mass % to the power of 0.3,

wherein, if zinc is present, a contained amount of zinc is greater than or equal to 0 mass % and less than or equal to 0.5 mass %, and

wherein, if oxygen is present, a contained amount of oxygen is greater than or equal to 0.0001 mass % and less than or equal to 2 mass %.

2. The composition of claim 1 ,

wherein the contained amount of iridium is less than or equal to 0.025 mass %.

3. The composition of claim 1 ,

wherein the contained amount of germanium is greater than 0.5 mass %,

wherein a sum of the contained amount of germanium and the contained amount of nickel is greater than 1.2 mass %, and

wherein a value obtained by dividing the contained amount of nickel in mass % by the contained amount of germanium in mass % is less than 2.0.

4. A method of bonding a material to be bonded provided with a bonding portion containing an oxide, the method comprising contacting the material with the composition for bonding according to claim 1 .

5. The method of claim 4 , wherein the bonding portion of the material to be bonded contains at least one type of oxide selected from the group consisting of a glass, a chrome oxide, and an aluminum oxide.

6. The composition of claim 1 ,

wherein in a cross section of the composition, a number of circles in a region with an area of 1.0×10 6 μm 2 , each circle inscribing a eutectic substance at a minimum diameter that is greater than or equal to 220 μm, is less than or equal to two, or a number of circles in the region with an area of 1.0×10 6 μm 2 , each circle inscribing a eutectic substance at a minimum diameter that is greater than or equal to 350 μm, is less than or equal to one.

7. The composition of claim 1 , wherein the contained amount of iridium is greater than or equal to 0.001 mass %.

8. The composition of claim 1 , wherein the contained amount of iridium is less than or equal to 0.005 mass %.

9. The composition of claim 1 , wherein a total amount of Fe, Co, Cr, V, Mn, Sb, Pb, Bi, Zn, As and Cd is less than or equal to 500 ppm.

10. The composition of claim 9 , wherein the contained amount of germanium is greater than 0.5 mass %,

wherein a sum of the contained amount of germanium and the contained amount of nickel is greater than 1.2 mass %, and

wherein a value obtained by dividing the contained amount of nickel in mass % by the contained amount of germanium in mass % is less than 2.0.

11. The composition of claim 9 , which does not contain Ag.

12. The composition of claim 9 , wherein the contained amount of germanium is greater than 0.5 mass %, and

wherein a sum of the contained amount of germanium and the contained amount of nickel is greater than 1.2 mass %.

13. The composition of claim 1 , wherein the contained amount of germanium is greater than 0.5 mass %, and

wherein a sum of the contained amount of germanium and the contained amount of nickel is greater than 1.2 mass %.

14. The composition of claim 1 , which does not contain Ag.

15. The composition of claim 14 , wherein the contained amount of iridium is greater than or equal to 0.001 mass %.

16. The composition of claim 14 , wherein the contained amount of iridium is less than or equal to 0.005 mass %.

17. The composition of claim 14 , wherein the contained amount of germanium is greater than 0.5 mass %,

wherein a sum of the contained amount of germanium and the contained amount of nickel is greater than 1.2 mass %.