Method for deposition of nitrogen doped silicon carbide films

• US 20040018750A1
• Filed: 07/02/2002
• Published: 01/29/2004
• Est. Priority Date: 07/02/2002
• Status: Abandoned Application

• Current Assignee: Asa Japan K.K.
• Original Assignee: Asa Japan K.K.
• Inventors: Ozaki, Fumitoshi, Sophie, Auguste J.L.
• Application Number:
  US10/188,723
• Publication Number:
  US 20040018750A1
• Time in Patent Office: Days
• US Class Current: 438/792
• 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 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/02208 the precursor containing a compound comprising Si
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/314 Inorganic layers H01L21/3105, H01L21/32 take precedence
• CPC Class Codes: H01L 21/76807 for dual damascene structures
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers

Abstract

Disclosed are processes for depositing a silicon carbonitride (Si—C—N) material and resulting films. The process involves plasma enhanced chemical vapor deposition (PECVD), in which chemical precursors for silicon and carbon are supported by nitrogen gas (N₂). Nitrogen gas not only supports the other chemical precursors and plasma species during the PECVD process, but also participates in the film formation. The nitrogen carrier gas is activated by plasma energy as other chemical precursors. Excited species of nitrogen gas react with excited species of silicon and carbon to deposit the Si—C—N material on a substrate. The use of nitrogen gas improves the stability of the plasma and eliminates arcing during the PECVD process. Further, the resulting Si—C—N material showed improved properties, such as less aging effects and improved thermal stability, as compared to processes using other carrier gases.

Claims

1. A method for depositing a silicon carbonitride (Si—

C—

N) material on a surface, comprising;

loading a substrate having a surface into a processing chamber;

introducing at least one chemical precursor and a carrier gas into the processing chamber, the carrier gas comprising nitrogen gas; and

applying an electromagnetic energy to the at least one chemical precursor and the carrier gas, thereby depositing on the surface of the substrate a Si—

C—

N material comprising silicon, carbon and nitrogen.

2. The method of claim 1, wherein the electromagnetic energy is sufficient to activate molecules of the at least one chemical precursor and carrier gas to create a plasma state.

3. The method of claim 1, wherein substantially all of the nitrogen contained in the deposited material originates from the nitrogen gas.

4. The method of claim 1, wherein the at least one chemical precursor includes a chemical precursor for silicon and a chemical precursor for carbon.

5. The method of claim 4, wherein the chemical precursor for silicon is selected from the group consisting of SiH₄, Si₂H₆, Si₃H₈, SiF₄, SiCl₄, SiCl₃ and HSiBr₃.

6. The method of claim 4, wherein the chemical precursor for carbon is one or more selected from the group consisting of CH₄, C₂H₆, C₃H₈, C₄H₁₀ and C₂H₄.

7. The method of claim 1, wherein the at least one chemical precursor is a single chemical compound comprising silicon and carbon elements.

8. The method of claim 6, wherein the single chemical compound is selected from the group consisting of methylsilane, dimethylsilane, trimethylsilane and tetramethylsilane.

9. A silicon carbonitride (Si—

C—

N) material deposited on a substrate according to the method of claim 1.

10. A method for forming a silicon carbonitride material by plasma enhanced chemical vapor deposition, comprising:

providing a substrate having a surface in a chamber; and

generating excited species of elements comprising silicon species, carbon species and nitrogen species, wherein the generated species are supported by a plasma supporting gas comprising nitrogen gas (N₂), and wherein the surface of the substrate is exposed to the excited species supported by the plasma supporting gas.

11. The method of claim 10, wherein the excited species are generated near the surface of the substrate.

12. A process for forming a layer comprising silicon and carbon in integrated circuit fabrication, comprising:

introducing into a chamber for plasma enhanced chemical vapor deposition (PECVD) one or more chemical precursors comprising silicon and carbon along with a carrier gas entraining the chemical precursors into the chamber; and

carrying out the PECVD in the chamber such that the carrier gas is activated to generate its own excited species, thereby depositing a layer comprising silicon, carbon and an element from the carrier gas on a substrate in a chamber.

13. The process of claim 12, wherein the element from the carrier gas is nitrogen.

14. The process of claim 13, wherein the carrier gas comprises nitrogen gas.