Method for copper filling of a hole in a component carrier
A method of filling a hole formed in a component carrier with copper is disclosed. The method comprises i) forming a layer of an electrically conductive material covering at least part of a surface of a wall, wherein the wall delimits the hole, and subsequently ii) covering at least partially the layer and filling at least partially an unfilled volume of the hole with copper using a plating process including a bath. Hereby, the bath comprises a concentration of a copper ion, in particular Cu 2+ , in a range between 50 g/L and 75 g/L, in particular in a range between 60 g/L and 70 g/L.
1. A method of filling a hole formed in a component carrier with copper, the method comprising:
forming a layer of an electrically conductive material covering at least part of a surface of a wall, wherein the wall delimits the hole; and
subsequently, covering at least partially the layer and filling at least partially an unfilled volume of the hole with copper using a plating process including a bath,
wherein the bath comprises a concentration of a copper ion in a range between 50 g/L and 75 g/L, and
wherein at least partially covering the layer and at least partially filling the hole are done by flash-plating.
2. The method according to claim 1 , further comprising: supplying the bath with copper sulfate (CuSO 4 ) and/or copper sulfate pentahydrate (CuSO 4 *5H 2 O).
3. The method according to claim 1 , wherein the bath further comprises:
sulfuric acid (H 2 SO 4 ) with a concentration in a range between 80 g/L and 110 g/L.
4. The method according to claim 1 , wherein the bath further comprises:
at least one of the group consisting of iron ions, chloride (Cl − ) a brightening agent, and a leveler agent.
5. The method according to claim 1 , further comprising:
filling at least partially a remaining volume of the hole with copper using a further plating process including a further bath, wherein the further bath comprises at least approximately the same composition of chemical ingredients and/or at least approximately the same concentration of chemical ingredients as the first bath.
6. The method according to claim 1 , further comprising:
filling at least partially a remaining volume of the hole with copper using a further plating process including a further bath, wherein the further bath comprises a different composition of chemical ingredients and/or a different concentration of chemical ingredients as the first bath.
7. The method according to claim 1 , wherein a formed layer of electrically conductive material comprises a thickness in a range between 0.1 μm and 1 μm, and/or
wherein a copper material, which has been formed above the formed layer of electrically conductive material, comprises a thickness in a range between 0.3 μm and 15 μm.
8. The method according to claim 1 , wherein forming the layer of electrically conductive material is done by electro-less plating.
9. The method according to claim 1 , further comprising:
drilling the hole with a laser; and
removing waste products caused by laser drilling.
10. The method according to claim 1 , further comprising:
drilling the hole with a laser; and
wherein the forming of the layer is performed without previously removing waste products caused by laser drilling.
11. The method according to claim 1 , wherein an aspect ratio of the hole is in a range between 0.5 and 1.5.
12. The method according to claim 1 , wherein the hole is configured as a through hole or as a blind hole.
13. The method according to claim 1 , wherein the electrically conductive material comprises at least one of the group consisting of copper, aluminum, and nickel.
14. The method according to claim 1 , wherein the copper ion is Cu 2+ .
15. The method according to claim 1 , wherein the bath comprises a concentration of the copper ion in a range between 60 g/L and 70 g/L.