Method for making a semiconductor device having increased conductive material reliability
View Patent ↗A method and apparatus for a semiconductor device having a semiconductor device having increased conductive material reliability is described. That method and apparatus comprises forming a conductive path on a substrate. The conductive path made of a first material. A second material is then deposited on the conductive path. Once the second material is deposited on the conductive path, the diffusion of the second material into the conductive path is facilitated. The second material has a predetermined solubility to substantially diffuse to grain boundaries within the first material.
1. A method for making a semiconductor device comprising:
forming a conductive path on a substrate, the conductive path made of copper;
removing an oxide from the conductive path by etching the conductive path with a medium having a mildly acidic or mildly basic solution;
depositing a metal more noble than copper on the conductive path, from an aqueous solution by immersion plating;
facilitating a diffusion of the metal more noble than copper into the conductive path, the metal more noble than copper having a low solubility to substantially diffuse into grain boundaries of the conductive path to significantly increase reliability of the conductive path; and
planarizing the conductive path after the facilitating to remove the deposited metal and a portion of the conductive path.
2. The method of claim 1 , wherein the metal more noble than copper comprises platinum.
3. The method of claim 1 , wherein the metal more noble than copper comprise rhodium.
4. The method of claim 1 , wherein forming the conductive path comprises a damascene process.
5. The method of claim 1 , wherein the metal more noble than copper comprises gold.
6. The method of claim 1 , wherein the metal more noble than copper comprises ruthenium.
7. The method of claim 1 , wherein the metal more noble than copper comprises osmium.
8. The method of claim 1 , wherein the metal more noble than copper comprises iridium.
9. The method of claim 1 , wherein depositing the more noble than copper comprises immersing the conductive path in an aqueous solution having at least the metal more noble than copper.
10. The method of claim 1 , wherein facilitating diffusion of the metal more noble than copper comprises heat treating the conductive path having the deposited metal more noble than copper.
11. The method of claim 10 , wherein heat treating the conductive path comprises annealing the conductive path to substantially diffuse the metal more noble than copper to the grain boundaries within the copper, the temperature and time based at least in part on the copper and the metal more noble than copper.
12. The method of claim 1 , wherein the conductive path comprises at least of one of a conductive line and a conductive interconnect.