Precursors for CVD silicon carbo-nitride films

• US 20060258173A1
• Filed: 05/16/2005
• Published: 11/16/2006
• Est. Priority Date: 05/16/2005
• Status: Active Grant

• Current Assignee: Versum Materials US Inc.
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: Hochberg, Arthur Kenneth, Xiao, Manchao
• Granted Patent: US 7,875,556 B2
• Time in Patent Office: Days
• US Class Current: 438/780
• CPC Class Codes: C07F 7/025 without C-silicon linkages
• CPC Class Codes: C09D 5/00 Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced electrically insulating plastics, resins or waxes H01B3/30; Filling pastes
• CPC Class Codes: C23C 16/36 Carbonitrides
• CPC Class Codes: H01L 21/02167 the material being a silicon carbide not containing oxygen, e.g. SiC, SiC:H or silicon carbonitrides H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/02219 the compound comprising silicon and nitrogen
• CPC Class Codes: H01L 21/02222 the compound being a silazane
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD

Abstract

Classes of liquid aminosilanes have been found which allow for the production of silicon carbo-nitride films of the general formula Si_xC_yN_z. These aminosilanes, in contrast, to some of the precursors employed heretofore, are liquid at room temperature and pressure allowing for convenient handling. In addition, the invention relates to a process for producing such films.
The classes of compounds are generally represented by the formulas:

• • and mixtures thereof, wherein R and R¹ in the formulas represent aliphatic groups typically having from 2 to about 10 carbon atoms, e.g., alkyl, cycloalkyl with R and R¹ in formula A also being combinable into a cyclic group, and R² representing a single bond, (CH₂)_n, a ring, or SiH₂.

Claims

1. A process for forming silicon carbo-nitride films on a substrate through chemical vapor deposition of a silicon carbo-nitride film forming precursor which comprises:

using a precursor selected from the group consisting of an aminosilane represented by the formulas;

and mixtures thereof, wherein R is selected from C₁-C₁₀ alkyl groups, linear, branched, or cyclic, saturated or unsaturated;

aromatic, heterocyclic, amine groups, or silyl in formula C, R¹ is selected from C₂-C₁₀ alkyl groups, linear, branched, or cyclic, saturated or unsaturated;

aromatic, heterocyclic, hydrogen, silyl groups with or without substituents with R and R¹ in formula A also being combinable into a cyclic group (CH₂)_n, wherein n is from 1-6, R and R in formula C also being combinable into a cyclic group and R² representing a single bond, (CH₂)_n chain, a ring, SiR₂, or SiH₂.

2. The process of claim 1 wherein the precursor is represented by the formula A and R and R¹ each have at least 2 carbon atoms.

3. The process of claim 2 wherein R and R¹ are alkyl groups having from 2-4 carbons.

4. The process of claim 2 wherein R and R¹ are cyclic

5. The process of claim 4 wherein R and R¹ are combined into a ring in the form of (CH₂)_n where n is from 4-5.

6. The process of claim 2 wherein R and R¹ are ethyl or isopropyl.

7. The process of claim 1 wherein a nitrogen source selected from the group consisting of ammonia, nitrogen and hydrazine is employed.

8. The process of claim 7 wherein the temperature of the substrate during chemical vapor deposition is within the range of approximately 500 to 700°

C.

9. The process of claim 8 wherein the pressure during chemical vapor deposition is in the range of approximately 20 mTorr to 20 Torr.

10. The process of claim 7 wherein the nitrogen source is ammonia or nitrogen and the nitrogen source is present in a nitrogen source:

precursor range of from 0.1 to 4;

1.

11. The process of claim 2 wherein the precursor aminosilane is selected from the aminosilanes having the formula:

12. The process of claim 1 wherein the precursor is represented by the formula B and within that class, the precursor is selected from the group having the formula:

13. The process of claim 12 wherein a nitrogen source selected from the group consisting of ammonia or nitrogen is included as precursor and the nitrogen source is present in a nitrogen source:

precursor range of from 0.1 to 4;

1.

14. The process of claim 1 wherein the precursor is represented by the formula C and within that class, the precursor is selected from the group having the formulas:

15. In a process for forming a silicon carbo-nitride film wherein such film is formed by the chemical vapor deposition of a silane precursor, the improvement for forming films having the general compositional structure Si_xC_yN_z which comprises:

employing an aminosilane as the silane precursor which is represented by the formula;

wherein R is selected from C₁-C₁₀ alkyl groups, linear, branched, or cyclic, saturated or unsaturated;

aromatic, heterocyclic and R¹ is selected from C₂-C₁₀ alkyl groups, linear, branched, or cyclic, heterocyclic, hydrogen, silyl groups with R and R¹ also being combinable into a cyclic group (CH₂)_n, wherein n is from 1-6.

16. The process of claim 15 wherein R and R¹ are ethyl or isopropyl.

17. The process of claim 16 wherein a nitrogen source selected from the group consisting of ammonia or nitrogen in employed in a nitrogen source:

silane precursor ratio of from 0.1 to 4;

1

18. The process of claim 17 wherein the temperature of the substrate is maintained with a range of 500 to 700°

C. and the pressure is from 20 mTorr to 20 Torr.