High-density plasma process for depositing a layer of silicon nitride

• US 6,953,609 B2
• Filed: 10/14/2003
• Issued: 10/11/2005
• Est. Priority Date: 10/11/2002
• Status: Expired due to Fees

• Current Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Carollo, Enzo
• Primary Examiner(s): CHEN, BRET P
• Application Number:
  US10/686,556
• Publication Number:
  US 20040137169A1
• Time in Patent Office: 728 Days
• Field of Search: 427/579, 427/255.37, 427/535, 438/789
• US Class Current: 427/579
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/455 characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber
• CPC Class Codes: C23C 16/507 using external electrodes, e.g. in tunnel type reactors
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz 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 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/3144 on silicon
• CPC Class Codes: H01L 21/3145 formed by deposition from a gas or vapour
• CPC Class Codes: H01L 21/3185 of siliconnitrides

Abstract

A high-density plasma process is proposed for depositing a layer of Silicon Nitride on a substrate in a plasma reactor. The process includes the steps of: providing a gas including precursor components of the Silicon Nitride, generating a plasma applying a radio-frequency power to the gas, and the plasma reacting with the substrate to deposit the layer of Silicon Nitride. The power applied to the gas is in the range from 2.5 kW to 4 kW.

Claims

1. A high-density plasma process for depositing a layer of Silicon Nitride on a substrate in a plasma reactor, the process including the steps of:

providing a gas including precursor components of the Silicon Nitride,

generating a plasma by applying a radio-frequency power to the gas, and

the plasma reacting with the substrate to deposit the layer of Silicon Nitride,

wherein the power applied to the gas is in the range from 2.5 kW to 4 kW, and wherein the process further includes the steps before the deposition of the layer of Silicon Nitride of;

providing a further gas including Oxygen,

generating a further plasma from the further gas, and

heating up the substrate by means of the further plasma, thereby generating a first oxide liner on the substrate.

2. The process according to claim 1, wherein the power applied to the gas is in the range from 2.9 kW to 3.2 kW.

3. The process according to claim 1, wherein the step of generating the plasma includes:

applying a first radio-frequency power to the gas by means of a first power source, and

applying a second radio-frequency power to the gas by means of a second power source, a ratio between the first power and the second power being in the range from 2.1 to 2.5.

4. The process according to claim 3, wherein the ratio between the first power and the second power is in the range from 2.2 to 2.4.

5. The process according to claim 1, wherein the step of providing the gas includes providing each precursor component at a flow rate in the range from 80% to 95% of a corresponding rated value supported by the reactor.

6. The process according to claim 1, further including the step of cooling the substrate during the deposition of the layer of Silicon Nitride.

7. The process according to claim 1, wherein the step of generating the further plasma includes applying the radio-frequency power to the further gas, the radio-frequency power being not removed between the heating up of the substrate and the deposition of the layer of Silicon Nitride.

8. The process according to claim 1, further including the step of cooling a surface of the substrate that is not exposed to the further plasma during the heating up of the substrate.

9. The process according to claim 1, further including the steps after the deposition of the layer of Silicon Nitride of:

providing a still further gas including Oxygen, generating a still further plasma from the still further gas to de-chuck the substrate from an electrostatic chuck, thereby generating a second oxide liner on the layer of Silicon Nitride.