METHOD OF PATTERNING PLATINUM LAYER

• US 20150037974A1
• Filed: 07/30/2013
• Published: 02/05/2015
• Est. Priority Date: 07/30/2013
• Status: Active Grant

• Current Assignee: United Microelectronics Corporation
• Original Assignee: United Microelectronics Corporation
• Inventors: Lu, Hsin-Yi, Wang, Jeng-Ho, Lin, Yu-Chi
• Granted Patent: US 9,006,105 B2
• Time in Patent Office: Days
• US Class Current: 438/653
• CPC Class Codes: B81B 7/0096 by heating
• CPC Class Codes: C23F 1/02 Local etching
• CPC Class Codes: C23F 1/12 Gaseous compositions
• CPC Class Codes: H01L 21/32135 by vapour etching only

Abstract

A method of patterning a platinum layer includes the following steps. A substrate is provided. A platinum layer is formed on the substrate. An etching process is performed to pattern the platinum layer, wherein an etchant used in the etching process simultaneously includes at least a chloride-containing gas and at least a fluoride-containing gas.

Claims

1. A method of patterning a platinum layer, comprising:

providing a substrate;

forming a platinum layer on the substrate; and

performing an etching process to pattern the platinum layer, wherein an etchant used in the etching process comprises at least a chloride-containing gas and at least a fluoride-containing gas, and a flow rate of the chloride-containing gas is substantially lower than a flow rate of the fluoride-containing gas.

2. The method of patterning a platinum layer according to claim 1, wherein the etchant comprises a specific gas ratio of the chloride-containing gas to the fluoride-containing gas.

4. The method of patterning a platinum layer according to claim 1, wherein the etchant comprises a variable gas ratio of the chloride-containing gas to the fluoride-containing gas.

5. The method of patterning a platinum layer according to claim 4, wherein the variable gas ratio comprises a gradually decreasing gas ratio.

6. The method of patterning a platinum layer according to claim 4, wherein the variable gas ratio of the chloride-containing gas to the fluoride-containing gas comprises a variable ratio of a flow rate of the chloride-containing gas to a flow rate of the fluoride-containing gas, and the variable gas ratio ranges from 0 to 1.

8. The method of patterning a platinum layer according to claim 1, wherein the fluoride-containing gas comprises SF₆, SF₄, CF₄, CHF₃, CH₂F₂, CH₃F or a combination thereof.

9. The method of patterning a platinum layer according to claim 1, wherein a formula of a component of the fluoride-containing gas has a number of fluorine equal to or lower than six.

10. The method of patterning a platinum layer according to claim 1, wherein the chloride-containing gas comprises Cl₂ or BCl₃.

11. The method of patterning a platinum layer according to claim 1, wherein the etchant further comprises a combustion gas.

12. The method of patterning a platinum layer according to claim 11, wherein the combustion gas comprises oxygen.

13. The method of patterning a platinum layer according to claim 1, wherein the etchant further comprises a noble gas.

14. The method of patterning a platinum layer according to claim 13, wherein the noble gas comprises argon.

15. The method of patterning a platinum layer according to claim 1, further comprising forming a barrier layer between the platinum layer and the substrate.

16. The method of patterning a platinum layer according to claim 15, wherein the barrier layer is made of titanium nitride (TiN) or tantalum nitride (TaN).

17. The method of patterning a platinum layer according to claim 1, wherein the substrate further comprises at least one conductive element stack and at least one dielectric layer disposed under the platinum layer.

3. (canceled)

7. (canceled)