Carbon materials for carbon implantation

• US 10,497,569 B2
• Filed: 11/17/2016
• Issued: 12/03/2019
• Est. Priority Date: 07/23/2009
• Status: Active Grant

• Current Assignee: Entegris Incorporated
• Original Assignee: Entegris Incorporated
• Inventors: Sweeney, Joseph D., Byl, Oleg, Kaim, Robert
• Primary Examiner(s): Menz, Laura M
• Assistant Examiner(s): Chan, Candice
• Application Number:
  US15/354,076
• Publication Number:
  US 20170069499A1
• Time in Patent Office: 1,111 Days
• CPC Class Codes: C23C 14/06 characterised by the coating material C23C14/0021 , C23C14/04 take precedence
• CPC Class Codes: C23C 14/0605 Carbon
• CPC Class Codes: C23C 14/48 Ion implantation
• CPC Class Codes: H01J 2237/08 Ion sources
• CPC Class Codes: H01J 2237/31701 Ion implantation
• CPC Class Codes: H01J 37/3171 for ion implantation
• CPC Class Codes: H01L 21/2236 from or into a plasma phase
• CPC Class Codes: H01L 21/265 producing ion implantation

Abstract

A method of implanting carbon ions into a target substrate, including: ionizing a carbon containing dopant material to produce a plasma having ions; optionally co-flowing an additional gas or series of gases with the carbon-containing dopant material; and implanting the ions into the target substrate. The carbon-containing dopant material is of the formula C_wF_xO_yH_z wherein if w=1, then x>0 and y and z can take any value, and wherein if w>1 then x or y is >0, and z can take any value. Such method significantly improves the efficiency of an ion implanter tool, in relation to the use of carbon source gases such as carbon monoxide or carbon dioxide.

Claims

1. A method of implanting carbon in a substrate from a carbon-containing dopant material, comprising:

flowing a carbon-containing dopant material comprising a carbon-containing gas;

into an ion implantation chamber;

ionizing the carbon-containing dopant material to form ions comprising positive carbon ions;

implanting the carbon ions in the substrate; and

flowing a fluorine-containing gas into the ion implantation chamber, while the carbon ions are being implanted, thereby increasing an amount of the carbon ions implanted in the substrate and reducing an amount of carbon or non-carbon elements deposited on the ion implantation chamber.

2. The method of claim 1, wherein an additional gas or gases, selected from the group consisting of oxygen, an oxygen-containing gas that is different than CO₂ and CO, air, hydrogen, nitrogen, argon, xenon, and helium, flows with the carbon-containing and fluorine-containing gases.

3. The method of claim 2, wherein the additional gas or gases comprises hydrogen or helium.

4. The method of claim 2, wherein the additional gas or gases comprises inert gas selected from the group consisting of nitrogen, argon, xenon, helium, and combinations thereof.

5. The method of claim 2, wherein the additional gas or gases comprises an oxygen-containing gas.

6. The method of claim 1, wherein the fluorine-containing gas comprises COF₂.

7. The method of claim 1, wherein the carbon-containing gas comprises CO.

8. The method of claim 1, wherein the carbon-containing gas comprises CO₂.

9. The method of claim 1, wherein the fluorine-containing gas comprises fluorine and carbon, oxygen, or both carbon and oxygen.

10. The method of claim 1, comprising implantation of multiple implantation species.

11. The method of claim 1, wherein the ionizing is conducted in an arc chamber of the ion implantation chamber, to which the carbon-containing and fluorine-containing gases are flowed.

12. The method of claim 1, comprising separating C⁺ ions via mass analysis.

13. The method of claim 1, wherein the carbon-containing and fluorine-containing gases, and an optional additional gas, comprise a gas combination selected from the group consisting of:

(i) CO+F₂;

(ii) CO+F₂+O₂;

(iii) CO+F₂+H₂;

(iv) CO+F₂+H₂+O₂;

(v) CO+COF₂;

(vi) CO+COF₂+H₂;

(vii) CO+CF₄;

(viii) CO+CH₃F;

(ix) CO+H₂+CF₄;

(x) CO+H₂+CH₃F;

(xi) CF₄+CH₄;

(xii) CF₄+CH₄+O₂;

(xiii) CO₂+F₂;

(xiv) CO₂+F₂+O₂;

(xv) CO₂+F₂+H₂;

(xvi) CO₂+F₂+H₂+O₂;

(xvii) CO₂+COF₂;

(xviii) CO₂+COF₂+H₂;

(xix) CO₂+CF₄;

(xx) CO₂+CH₃F;

(xxi) CO₂+H₂+CF₄; and

(xxii) CO₂+H₂+CH₃F.

14. The method of claim 1 wherein the carbon-containing gas and fluorine-containing gas comprises CO, CO₂, or both CO and CO₂, and COF₂.

15. The method of claim 14 wherein ionizing generates carbon ions, oxygen ions, and fluorine ions from the CO, CO₂, or both CO and CO₂, and COF₂.

16. The method of claim 15 wherein CO, CO₂, or both CO and CO₂, and COF₂, are present in a molar ratio which maximizes that amount of carbon implanted and minimizes the amounts of carbon or non-carbon elements deposited on the chamber.

17. The method of claim 1 which minimizes carbon, non-carbon elements, or both, deposited on the ion implantation chamber.

18. The method of claim 1 wherein ionizing generates fluorine ions and fluorine ions minimize oxidation of a cathode or filament in the ion implantation chamber.

19. The method of claim 1 wherein, the fluorine-containing gas is introduced into the ion implantation chamber as a co-flow with the carbon-containing gas.

20. The method of claim 1 wherein, the fluorine-containing gas is simultaneously flowed with the carbon-containing gas.