Soldering method, component to be joined by the soldering method, and joining structure
View Patent ↗It is possible to prevent deterioration of a soldering portion and improve strength of thermal fatigue resistance by providing barrier metal layers on at least one of lead and land to cover parent materials comprising Cu-containing materials, feeding a soldering material between the lead and the land and allowing to contact in a fused condition with barrier metal layers and solidify, and thus soldering together the lead and the land.
1. A joined structure, comprising; first and second members, the first member comprising Cu;
a soldering material comprising Sn and Zn between the first and second members; and
a layer comprising an Au-Zn compound between the first member and the soldering material, the Au-Zn compound being formed in a layer state,
wherein there is no elution or fusion diffusion of the Au into the soldering material.
2. The joined structure of claim 1 , wherein a thickness of the layer comprising the Au—Zn compound in a layer state is about 0.01 to about 0.1 μm.
3. The joined structure of claim 1 , further comprising a barrier metal layer between the first member and the layer comprising an Au—Zn compound in a layer state.
4. The joined structure of claim 3 , wherein the barrier metal layer comprises Ni.
5. The joined structure of claim 3 , wherein the barrier metal layer comprises a Ni layer and an Au layer, the Ni layer being adjacent to the first member.
6. The joined structure of claim 1 , wherein the second member comprising Cu, and the structure further comprises a second layer comprising an Au—Zn compound between the second member and the soldering material, the Au—Zn compound being a layer state, not a granular state.
7. The joined structure of claim 6 , wherein a thickness of the second layer comprising the Au-Zn compound in a layer state is about 0.01 to about 0.1 μm.
8. The joined structure of claim 6 further comprising at least one of a first barrier metal layer between the first member and the layer comprising an Au—Zn compound or a second barrier metal layer between the second member and the second layer comprising an Au—Zn compound, the Au—Zn compounds being a layer state, not a granular state.
9. The joined structure of claim 8 , wherein the first and second barrier metal layers comprise Ni.
10. The joined structure of claim 8 , wherein the first and second barrier metal layers comprise Ni layers and Au layers, the Ni layers being adjacent to the first and second members, respectively.
11. A joined structure; comprising; a lead of an electronic component and a land on a board, the land comprising Cu;
a soldering material comprising Sn and Zn between the lead and land;
a layer comprising an Au—Zn compound between the land and the soldering material, the Au—Zn compound being formed in a layer state,
wherein there is no elution or fusion diffusion of the Au into the soldering material.
12. The joined structure of claim 11 , wherein a thickness of the layer comprising the Au—Zn compound in a layer state is about 0.01 to about 0.1 μm.
13. The joined structure of claim 12 further comprising a barrier metal layer between the land and the layer comprising the Au—Zn compound in a layer state.
14. The joined structure of claim 13 , wherein the barrier metal layer comprises Ni.
15. The joined structure of claim 13 , wherein the barrier metal layer comprises a Ni layer and an Au layer, the Ni layer being adjacent to the land.
16. The joined structure of claim 11 , wherein the lead comprises Cu, and the structure further comprises a second layer comprising an Au—Zn compound between the lead and the soldering material, the Au—Zn compound being a layer state, not a granular state.
17. The joined structure of claim 16 , wherein a thickness of the second layer comprising the Au—Zn compound in a layer state is about 0.01 to about 0.1 μm.
18. The joined structure of claim 16 further comprising a first barrier metal layer between the land and the layer comprising the Au—Zn compound and a second barrier metal layer between the lead and the second layer comprising the Au—Zn compound.
19. The joined structure of claim 18 , wherein the barrier metal layers comprise Ni.
20. The joined structure of claim 18 , wherein the barrier metal layers comprise Ni layers and Au layers, the Ni layers being adjacent to the land and lead, respectively.