Packaging deposition methods
View Patent ↗The present invention relates to a method for fabricating high performance chip interconnects and packages by providing methods for depositing a conductive material in cavities of a substrate in a more efficient and time saving manner. This is accomplished by selectively removing portions of a seed layer from a top surface of a substrate and then depositing a conductive material in the cavities of the substrate, where portions of the seed layer remains in the cavities. Another method includes forming an oxide layer on the top surface of the substrate such that the conductive material can be deposited in the cavities without the material being formed on the top surface of the substrate. The present invention also discloses methods for forming multi-level interconnects and the corresponding structures.
1. A method for depositing a conductive material in cavities of a substrate having a barrier layer and a seed layer formed thereon, the method comprising the steps of:
removing certain portions of the seed layer from the top surface of the substrate using a pad material while preventing removal of other portions of the seed layer from the cavities of the substrate by applying an electric potential between the substrate and an electrode;
exposing portions of the barrier layer on the top surface of the substrate after removing certain portions of the seed layer;
depositing the conductive material on the seed layer in the cavities of the substrate; and
positioning the pad material between 1 micron to 2 millimeters from the substrate during the depositing step.
2. A method for depositing a conductive material in cavities of a substrate having a barrier layer and a seed layer formed thereon, the method comprising the steps of:
removing certain portions of the seed layer from the top surface of the substrate using a pad material while preventing removal of other portions of the seed layer from the cavities of the substrate by applying an electric potential between the substrate and an electrode;
exposing portions of the barrier layer on the top surface of the substrate after removing certain portions of the seed layer;
depositing the conductive material on the seed layer in the cavities of the substrate; and
positioning the pad material on the substrate during the depositing step.
3. A method according to claim 2 , wherein the pad material is positioned on the substrate at a pressure between 0.05 to 5 pounds per square inch.
4. A method for depositing a conductive material in cavities of a substrate having a barrier layer and a seed layer formed thereon, the method comprising the steps of:
removing certain portions of the seed layer from the top surface of the substrate using a pad material while preventing removal of other portions of the seed layer from the cavities of the substrate by applying an electric potential between the substrate and an electrode;
exposing portions of the barrier layer on the top surface of the substrate after removing certain portions of the seed layer;
depositing the conductive material on the seed layer in the cavities of the substrate while positioning the pad material between 1 micron to 2 millimeters from the substrates; and
applying a first electric potential between the seed layer and an electrode having the pad material attached thereto, the first electric potential being applied during the step of preventing removal of other portions of the seed layer from the cavities of the substrate.
5. A method according to claim 4 , wherein applying the first electric potential makes the seed layer more negative than the electrode.
6. A method according to claim 4 , further comprising the step of applying a second electric potential between the seed layer and the electrode, the second electric potential being applied during the step of depositing.
7. A method according to claim 6 , wherein the value of the second electric potential is greater than the value of the first electric potential.