Silicon carbide deposited by high density plasma chemical-vapor deposition with bias

• US 6,926,926 B2
• Filed: 09/10/2001
• Issued: 08/09/2005
• Est. Priority Date: 09/10/2001
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: M'Saad, Hichem, Cho, Seon-Mee, Moghadam, Farhad
• Primary Examiner(s): Meeks, Timothy
• Assistant Examiner(s): FLETCHER III, WILLIAM P
• Application Number:
  US09/953,685
• Publication Number:
  US 20030049388A1
• Time in Patent Office: 1,429 Days
• Field of Search: 118/715, 118/728, 427/577, 427/578, 427/249.15, 427/99, 438/778
• US Class Current: 427/249.15
• CPC Class Codes: C23C 16/325 Silicon carbide
• CPC Class Codes: C23C 16/507 using external electrodes, e.g. in tunnel type reactors
• 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 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/314 Inorganic layers H01L21/3105, H01L21/32 take precedence

Abstract

A SiC-based layer is deposited on a substrate having an electrical resistivity between about 1 and 100 Ω cm. The substrate is disposed in a process chamber. A gaseous mixture having a silicon-containing gas and a hydrocarbon-containing gas is flowed to the process chamber. A high-density plasma, having an ion density greater than about 10¹¹ ions/cm³ is generated from the plasma. A small electrical bias, between about 0.65 and 1.30 W/cm², is applied to the substrate. The low bias compensates for an unexpected cooling that results when depositing the SiC-based layer but is low enough that implantation of hydrogen is minimized.

Claims

1. A method for depositing a layer over a substrate disposed in a process chamber, the substrate having an electrical resistivity between about 1 and 100 Ω

cm, the method comprising;

flowing a gaseous mixture comprising a silicon-containing gas and a hydrocarbon-containing gas to the process chamber;

generating a plasma from the gaseous mixture, the plasma having an ion density greater than about 10¹¹ ions/cm³; and

applying an electrical bias to the substrate, the electrical bias having a power density between about 0.65 and 1.30 W/cm².

2. The method recited in claim 1 wherein a ratio of a flow rate of the hydrocarbon-containing gas to a flow rate of the silicon-containing gas is less than 30 and greater than 10.

3. The method recited in claim 2 wherein the flow rate of the hydrocarbon-containing gas is between 150 and 300 sccm.

4. The method recited in claim 1 wherein the hydrocarbon-containing gas comprises an alkane.

5. The method recited in claim 4 wherein the alkane is selected from the group consisting of methane CH₄, ethane C₂H₆, butane C₃H₃, propane C₄H₁₀, pentane C₅H₁₂, and hexane C₆H₁₄.

6. The method recited in claim 1 wherein the silicon-containing gas comprises a silane.

7. The method recited in claim 6 wherein the silane is selected from the group consisting of monosilane SiH₄, disilane Si₂H₆, trisilane Si₃H₈, tetrasilane Si₄H₁₀, pentasilane Si₅H₁₂, and hexasilane Si₆H₁₄.

8. The method recited in claim 1 wherein the gaseous mixture further comprises an inert gas.

9. The method recited in claim 1 wherein the gaseous mixture consists essentially of an alkane, a silane, and an inert gas.

10. The method recited in claim 1 wherein the layer has an atomic carbon:

silicon ratio less than about 7;

1.

11. The method recited in claim 1 wherein the layer is part of an intermetal dielectric layer in a damascene structure.

12. The method recited in claim 1 wherein the layer is part of a printer-head structure.

13. The method recited in claim 1 wherein the layer has an electrical breakdown field greater than about 20 MV/cm and a leakage current density less than about 10-7 A/cm².

14. The method recited in claim 13 wherein the layer forms part of a fuse in a programmable logic device.

15. A computer-readable storage medium having a computer-readable program embodied therein for directing operation of a substrate processing system including a process chamber;

a plasma generation system;

a substrate holder;

a gas delivery system configured to introduce gases into the process chamber, the computer-readable program including instructions for operating the substrate processing system to form a layer on a substrate disposed in the processing chamber, the substrate having an electrical resistivity between about 1 and 100 Ω

cm, in accordance with the following;

flowing a gaseous mixture comprising a silicon-containing gas and a hydrocarbon-containing gas to the process chamber;

generating a plasma from the gaseous mixture, the plasma having an ion density greater than about 10¹¹ ions/cm³; and

applying an electrical bias to the substrate, the electrical bias having a power density between about 0.65 and 1.30 W/cm².

16. The computer-readable storage medium recited in claim 15 wherein a flow rate of the hydrocarbon-containing gas to a flow rate of the silicon-containing gas is less than 30 and greater than 10.

17. A substrate processing system comprising:

a housing defining a process chamber;

a plasma-generating system coupled to the process chamber;

a substrate holder, configured to hold a substrate during substrate processing;

a bias generator coupled to the substrate holder;

a gas-delivery system configured to introduce gases into the process chamber;

a controller for controlling the gas delivery system and the plasma generating system; and

a memory coupled to the controller comprising a computer-readable medium having a computer-readable program embodied therein for directing operation of the substrate processing system, the computer-readable program including;

instructions directing the gas delivery system to flow a gaseous mixture comprising a silicon-containing gas and a hydrocarbon-containing gas to the process chamber;

instructions directing the plasma-generating system to generate a plasma from the gaseous mixture, the plasma having an ion density greater than about 10¹¹ ions/cm³; and

instructions directing the bias generator to apply an electrical bias to the substrate, the electrical bias having a power density between about 0.65 and 1.30 W/cm².

18. The substrate processing system recited in claim 17 wherein a flow rate of the hydrocarbon-containing gas to a flow rate of the silicon-containing gas is less than 30 and greater than 10.