Method of Forming an Aluminum Oxide Layer, Metal Surface with Aluminum Oxide Layer, and Electronic Device

Patent metadata

Field	Value
Publication number	US-2018366427-A1
Application number	US-201816012341-A
Country	US
Kind code	A1
Filing date	Jun 19, 2018
Priority date	Jun 20, 2017
Publication date	Dec 20, 2018
Grant date	—

Abstract

A method of forming an aluminum oxide layer is provided. The method includes providing a metal surface including at least one metal of a group of metals, the group of metals consisting of copper, aluminum, palladium, nickel, silver, and alloys thereof. The method further includes depositing an aluminum oxide layer on the metal surface by atomic layer deposition, wherein a maximum processing temperature during the depositing is 280° C., such that the aluminum oxide layer is formed with a surface having a liquid solder contact angle of less than 40°.

First claim

What is claimed is:

1 . A method of forming an aluminum oxide layer, the method comprising:
providing a metal surface comprising at least one metal of a group of metals, the group of metals consisting of copper, aluminum, palladium, nickel, silver, and alloys thereof; and depositing an aluminum oxide layer on the metal surface by atomic layer deposition, wherein a maximum processing temperature during the depositing is 280° C., such that the aluminum oxide layer is formed with a surface having a liquid solder contact angle of less than 40°.

2 . The method of claim 1 , wherein the processing temperature during the depositing is between 150° and 280° C.

3 . The method of claim 2 , wherein a total duration of the processing temperature being between 150° C. and 280° C. is more than 30 minutes.

4 . The method of claim 3 , wherein the total duration of the processing temperature comprises an annealing process.

5 . The method of claim 1 , wherein the aluminum oxide layer comprises copper at a percentage by mass of at least 5 wt %.

6 . The method of claim 1 , wherein the liquid solder is a lead-free solder.

7 . The method of claim 1 , wherein the liquid solder comprises tin.

8 . The method of claim 1 , wherein the aluminum oxide layer has a thickness of between 1 nm and 12 nm.

9 . The method of claim 1 , further comprising:
between providing the metal surface and depositing the aluminum oxide layer, removing an oxide layer from the metal surface.

10 . The method of claim 9 , wherein the oxide layer is removed using a forming gas.

11 . A surface structure, comprising:
a metal surface comprising at least one metal of a group of metals, the group of metals consisting of copper, aluminum, palladium, nickel, silver, and alloys thereof, and an aluminum oxide layer deposited on the metal surface, wherein the aluminum oxide layer has a surface having a liquid solder contact angle of less than 40°.

12 . The surface structure of claim 11 , wherein the aluminum oxide layer has a thickness of between 1 nm and 12 nm.

13 . The surface structure of claim 11 , wherein the aluminum oxide layer comprises copper at a percentage by mass of at least 5 wt %.

14 . The surface structure of claim 11 , wherein the liquid solder is a lead-free solder.

15 . The surface structure of claim 11 , wherein the liquid solder comprises tin.

16 . An electronic device, comprising:
a surface structure comprising a metal surface comprising at least one metal of a group of metals, the group of metals consisting of copper, aluminum, palladium, nickel, silver, and alloys thereof, and an aluminum oxide layer deposited on the metal surface, wherein the aluminum oxide layer has a surface having a liquid solder contact angle of less than 40°; and a metal contact structure electrically conductively contacting the metal surface through or by the aluminum oxide layer.

17 . The electronic device of claim 16 , wherein the electrically conductive contact between the metal contact structure and the metal surface is a soldered contact.

18 . The electronic device of claim 17 , wherein the soldered contact comprises a lead-free solder.

19 . The electronic device of claim 17 , wherein the soldered contact comprises tin.

20 . The electronic device of claim 16 , wherein the metal contact structure is a bond wire.

21 . The electronic device of claim 20 , wherein the bond wire comprises copper or aluminum or gold.

Assignees

• Infineon Technologies Ag

Inventors

• Rogalli Michael
• Gatterbauer Johann
• Lehnert Wolfgang
• Matoy Kurt
• Napetschnig Evelyn
• Schneegans Manfred
• Weidgans Bernhard

Classifications

• H10W72/07636

  Soldering or alloying · CPC title

• H10W72/5525

  comprising copper [Cu] · CPC title

• H10W72/5524

  comprising aluminium [Al] · CPC title

• H10W72/5522

  comprising gold [Au] · CPC title

• H10W72/01971

  Cleaning, e.g. oxide removal · CPC title