ELECTRONIC DEVICE HAVING A BRASABLE METAL PAD COVER AND ASSOCIATED METHOD
In accordance with various embodiments of the present disclosure, an electronic device is provided. In some embodiments, the electronic device comprises a semiconductor substrate, an aluminum pad on the semiconductor substrate, and a stack. The stack comprises, in sequence, a barrier layer directly deposited on the aluminum pad, a seed layer directly deposited on the barrier layer, the seed layer comprising copper and having a thickness less than 800 nanometers, and a metal layer directly deposited on the seed layer, the metal layer comprising nickel and palladium.
1 . An electronic device comprising:
a semiconductor substrate;
an aluminum pad on the semiconductor substrate; and
a stack comprising, in sequence:
a barrier layer directly deposited on the aluminum pad;
a seed layer directly deposited on the barrier layer, the seed layer comprising copper and having a thickness less than 800 nanometers (nm); and
a metal layer directly deposited on the seed layer, the metal layer comprising nickel and palladium.
2 . The electronic device of claim 1 , wherein the metal layer comprises a first metal sub-layer comprising nickel directly deposited on the seed layer and a second metal sub-layer comprising palladium directly deposited on the first metal sub-layer.
3 . The electronic device of claim 2 , wherein the first metal sub-layer entirely covers a top surface of the seed layer.
4 . The electronic device of claim 2 , wherein the metal layer consists of the first and second metal sub-layers.
5 . The electronic device of claim 1 , wherein the seed layer has a thickness of 250-600 nm.
6 . The electronic device of claim 1 , wherein the metal layer has a thickness greater than 500 nm.
7 . The electronic device of claim 1 , wherein a sectional view of the seed layer has a substantially constant width from the barrier layer to the metal layer.
8 . The electronic device of claim 1 , wherein the seed layer consists of a single layer of copper.
9 . The electronic device of claim 1 , wherein the barrier layer comprises titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride.
10 . The electronic device of claim 1 , wherein the barrier layer consists of a layer made of titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride.
11 . A method of manufacturing an electronic device, the method comprising:
providing an aluminum pad on a semiconductor substrate of the electronic device; and
forming a stack on the aluminum pad, the forming comprising:
depositing a barrier layer directly on the aluminum pad;
depositing a seed layer directly on the barrier layer, the seed layer comprising copper and having a thickness less than 800 nanometers (nm); and
depositing a metal layer directly on the seed layer, the metal layer comprising nickel and palladium.
12 . The method of claim 11 , wherein depositing the metal layer is performed via electroless deposition.
13 . The method of claim 11 , wherein depositing the barrier layer and the seed layer are performed via physical vapor deposition.
14 . The method of claim 11 , wherein depositing the metal layer directly on the seed layer comprises depositing a first metal sub-layer comprising nickel directly on the seed layer and depositing a second metal sub-layer comprising palladium directly on the first metal sub-layer.
15 . The method of claim 14 , wherein the first metal sub-layer substantially entirely covers a top surface of the seed layer.
16 . The method of claim 11 , wherein the seed layer is deposited with a thickness of 250-600 nm. 17 The method of claim 11 , wherein the metal layer is deposited with a thickness greater than 500 nm.
18 . The method of claim 11 , wherein a sectional view of the seed layer has a substantially constant width from the barrier layer to the metal layer.
19 . The method of claim 11 , wherein the seed layer is deposited as a single layer of copper.
20 . The method of claim 11 , wherein the barrier layer is deposited as a single layer of titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride.