Germanium etching systems and methods

• US 10,043,674 B1
• Filed: 08/04/2017
• Issued: 08/07/2018
• Est. Priority Date: 08/04/2017
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Korolik, Mikhail, Ingle, Nitin, Kioussis, Dimitri
• Primary Examiner(s): Luu, Chuong A
• Application Number:
  US15/669,362
• Time in Patent Office: 368 Days
• Field of Search: 438479
• CPC Class Codes: C23F 4/00 Processes for removing metallic material from surfaces, not provided for in group C23F1/00 or C23F3/00
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/32422 Arrangement for selecting ions or species in the plasma
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: H01J 37/32477 characterised by the means for protecting vessels or internal parts, e.g. coatings
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching

Abstract

Exemplary methods for etching a germanium-containing material may include forming a plasma of a fluorine-containing precursor in a remote plasma region of a semiconductor processing chamber. The methods may include flowing effluents of the fluorine-containing precursor through apertures defined in a chamber component. The apertures may be coated with a catalytic material. The methods may include reducing a concentration of fluorine radicals in the plasma effluents with the catalytic material. The methods may also include delivering the plasma effluents to a processing region of the semiconductor processing chamber. A substrate having an exposed region of a germanium-containing material may be housed within the processing region. The methods may further include etching the germanium-containing material.

Claims

1. A method of etching a germanium-containing material, the method comprising:

forming a plasma of a fluorine-containing precursor in a remote plasma region of a semiconductor processing chamber;

flowing plasma effluents of the fluorine-containing precursor through apertures defined in a chamber component, wherein the apertures are coated with a catalytic material;

reducing a concentration of fluorine radicals in the plasma effluents with the catalytic material;

delivering the plasma effluents to a processing region of the semiconductor processing chamber, wherein a substrate comprising a germanium-containing material is housed in the processing region; and

etching the germanium-containing material.

2. The method of etching a germanium-containing material of claim 1, wherein the catalytic material comprises one or more materials including an element selected from the group consisting of nickel, cobalt, vanadium, niobium, tantalum, chromium, manganese, rhenium, iron, ruthenium, osmium, palladium, platinum, rhodium, and iridium.

3. The method of etching a germanium-containing material of claim 1, wherein the chamber component is maintained at a temperature above about 70°

C.

4. The method of etching a germanium-containing material of claim 1, wherein the substrate is maintained at a temperature below about 30°

C.

5. The method of etching a germanium-containing material of claim 1, wherein the germanium-containing material comprises SiGe.

6. The method of etching a germanium-containing material of claim 1, wherein the germanium-containing material is a first germanium-containing material, wherein the first germanium-containing material is etched relative to silicon or a second germanium-containing material, and wherein the second germanium-containing material is characterized by a lower germanium concentration than the first germanium-containing material.

7. The method of etching a germanium-containing material of claim 6, wherein the etching has a selectivity towards the first germanium-containing material relative to the silicon or the second germanium-containing material greater than or about 300:

1.

8. The method of etching a germanium-containing material of claim 1, wherein a pressure within the processing chamber is maintained above about 2 Torr.

9. The method of etching a germanium-containing material of claim 1, wherein the chamber component comprises a showerhead or an ion suppressor.

10. A method of etching a germanium-containing material, the method comprising:

forming a plasma of a fluorine-containing precursor in a remote plasma region of a semiconductor processing chamber;

flowing plasma effluents of the fluorine-containing precursor through a chamber component comprising a catalytic material;

catalytically converting at least a portion of fluorine radicals in the plasma effluents by the catalytic material;

delivering the plasma effluents to a processing region of the semiconductor processing chamber, wherein a substrate comprising a germanium-containing material is housed in the processing region; and

etching the germanium-containing material.

11. The method of etching a germanium-containing material of claim 10, wherein the converting comprises forming materials including at least two fluorine atoms from fluorine radicals on the catalytic material.

12. The method of etching a germanium-containing material of claim 10, wherein the chamber component comprises one or more of a remote plasma unit delivery tube, a blocker plate, a faceplate, an ion suppressor, or a showerhead.

13. The method of etching a germanium-containing material of claim 10, wherein the catalytic material comprises one or more materials including an element selected from the group consisting of nickel, cobalt, vanadium, niobium, tantalum, chromium, manganese, rhenium, iron, ruthenium, osmium, palladium, platinum, rhodium, and iridium.

14. The method of etching a germanium-containing material of claim 10, wherein the chamber component is maintained at a temperature above about 70°

C.

15. The method of etching a germanium-containing material of claim 10, wherein the substrate is maintained at a temperature below about 30°

C.

16. The method of etching a germanium-containing material of claim 10, wherein a pressure within the processing chamber is maintained between about 1 Torr and about 30 Torr.

17. A method of etching a germanium-containing material, the method comprising:

forming a plasma of a fluorine-containing precursor in a remote plasma region of a semiconductor processing chamber;

flowing plasma effluents of the fluorine-containing precursor through apertures defined in a chamber component, wherein the apertures are coated with a catalytic material, and wherein the chamber component is maintained at a temperature between about 70°

C. and about 150°

C.;

reducing a concentration of fluorine radicals in the plasma effluents with the catalytic material;

delivering the plasma effluents to a processing region of the semiconductor processing chamber, wherein a substrate comprising a germanium-containing material is housed in the processing region, and wherein the substrate is maintained at a temperature below about 30°

C.; and

etching the germanium-containing material.

18. The method of etching a germanium-containing material of claim 17, wherein the catalytic material comprises one or more materials including an element selected from the group consisting of nickel, cobalt, vanadium, niobium, tantalum, chromium, manganese, rhenium, iron, ruthenium, osmium, palladium, platinum, rhodium, and iridium.

19. The method of etching a germanium-containing material of claim 17, wherein a pressure within the processing chamber is maintained between about 1 Torr and about 30 Torr.

20. The method of etching a germanium-containing material of claim 17, wherein the chamber component comprises a showerhead or an ion suppressor.