Binary Ag—Cu amorphous thin-films for electronic applications

Patent metadata

Field	Value
Publication number	US-10822692-B2
Application number	US-201715676189-A
Country	US
Kind code	B2
Filing date	Aug 14, 2017
Priority date	Aug 12, 2016
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

An interconnect and a method of making an interconnect between one or more features on a substrate comprises: sputtering a noble metal-copper eutectic thin film under controlled power on an oxide grown or deposited on a substrate; and forming an amorphous alloy structure from the noble metal-copper eutectic thin film in the shape of the interconnect and the interconnect comprising no grain or grain boundaries without temperature sensitive resistivity.

First claim

What is claimed is:

1. A method of making an interconnect between one or more features on a substrate comprising:
growing or depositing a thermal oxide on the substrate;
sputtering a noble metal-copper metallic alloy glass thin film under controlled power on the thermal oxide, wherein the noble metal-copper metallic alloy glass thin film comprises 20 to 70 at % copper and a remainder at % noble metal; and
forming the noble metal-copper metallic alloy glass thin film into the interconnect, wherein the noble metal-copper metallic alloy glass thin film is amorphous.

2. The method of claim 1 , wherein the noble metal is selected from at least one of ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, or gold.

3. The method of claim 1 , further comprising using a temperature gradient assist during the sputtering.

4. The method of claim 1 , wherein the noble metal-copper metallic alloy glass thin film is a eutectic that comprises between 60 to 80 at % noble metal and a remainder at % copper.

5. The method of claim 1 , wherein the noble metal-copper metallic alloy glass thin film is a eutectic.

6. The method of claim 1 , further comprising using a deposition rate of 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0 Å/s during the sputtering.

7. The method of claim 1 , wherein the controlled power is defined further as a low power sputtering at about 20, 30, 40, 50, 60, 70, 80 or 90 watts.

8. The method of claim 1 , wherein the sputtering is performed using a DC magnetron.

9. The method of claim 1 , further comprising using a base pressure and a deposition pressure between ˜10 −7 Torr and ˜10 −3 Torr during the sputtering.

10. The method of claim 1 , further comprising maintaining a temperature of the substrate at about 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25° C.

11. The method of claim 1 , wherein the substrate is a silicon substrate.

12. The method of claim 1 , wherein the interconnect shows little to no change in resistivity in a temperature range of 77K to 340K.

13. The method of claim 1 , wherein a resistivity of the noble metal-copper metallic alloy glass thin film is generally independent of temperature.

14. A method of making an interconnect between one or more features on a substrate comprising:
sputtering an Au or Ag-copper eutectic thin film under controlled power on an oxide grown or deposited on the substrate, wherein the Au or Ag-copper eutectic thin film comprises 20 to 70 at % copper and a remainder at % Au or Ag; and
forming an amorphous alloy structure from the Au or Ag-copper eutectic thin film in the shape of the interconnect and the interconnect comprising no grain or grain boundaries without temperature sensitive resistivity.

15. The method of claim 14 , wherein a resistivity of the Au or Ag-copper eutectic thin film is generally independent of temperature.

Assignees

• Univ North Texas

Inventors

• Mukherjee Sundeep
• Das Santanu

Classifications

• H10W72/00

  Interconnections or connectors in packages · CPC title

• H10D86/85

  characterised by only passive components · CPC title

• C23C14/542

  Controlling the film thickness or evaporation rate · CPC title

• C23C14/185

  by cathodic sputtering · CPC title

• C22C5/08

  with copper as the next major constituent · CPC title