Method for solving the water stain residual defect after cleaning silicon carbonitride

Abstract

The application discloses a method for solving water stain residual defects after silicon carbonitride cleaning, which comprises the following steps: step S1, providing a semiconductor substrate; step S2, depositing a silicon carbonitride film on the semiconductor substrate; step S3, performing carbon dioxide plasma treatment on the semiconductor device after step S2; and step S4, performing subsequent processes. The application can effectively remove the ammonia component without affecting the quality of the NDC film, so that the etching barrier layer NDC can remove large-particle defects through a water washing process, and the yield loss caused by the water stain defects due to the random generation of large-particle defects in the NDC process can be avoided.

Description

Technical Field

[0001] This invention relates to the field of semiconductors, and more specifically to a method for solving the defect of water stains remaining after cleaning silicon carbonitride. Background Technology

[0002] With the development of integrated circuit manufacturing processes, many new thin films have been applied to device manufacturing processes to improve device performance due to their inherent advantages. Silicon carbonitride (NDC), with its larger etch selectivity compared to silicon oxide films and lower dielectric constant compared to traditional etch barrier layers like silicon nitride, is widely used as an etch barrier layer and hard mask layer in various technology nodes such as 55 / 40 / 28 / 22 / 14nm. Meanwhile, as the critical dimensions of each technology node continue to shrink, the requirements for particle defects during the fabrication process become increasingly stringent. However, particle defects randomly generated by the environment of the thin film processing equipment during fabrication are unavoidable. This necessitates the addition of a water washing process after thin film processing to reduce surface particle defects and thus minimize yield losses caused by particle defects. Figure 1 As shown, the presence or absence of a water washing process after thin film processing results in drastically different levels of wire breakage; that is, the wire breakage performance is better after water washing. However, in actual integrated circuit wafer fabrication, NDC thin films require a high nitrogen doping level, leading to the addition of a large amount of ammonia gas during the NDC deposition process. This results in a large amount of alkaline ammonia components on the surface of the deposited NDC thin film. Consequently, NDC thin films are more prone to water stain defects after a carbon dioxide-containing acidic water washing process, such as... Figure 2 As shown. Summary of the Invention

[0003] The technical problem to be solved by this invention is that water stain defects are more likely to occur after the acidic water washing process with carbon dioxide.

[0004] To address the aforementioned technical problems, this invention discloses a method for resolving water stain residue defects after cleaning silicon carbonitride, comprising the following steps:

[0005] Step S1: Provide a semiconductor substrate;

[0006] Step S2: Deposit a silicon carbonitride thin film on the semiconductor substrate;

[0007] Step S3: Perform carbon dioxide plasma treatment on the semiconductor device after step S2;

[0008] Step S4: Proceed with subsequent processes.

[0009] Preferably, the carbon dioxide plasma treatment is carried out at a pressure of 3-10 Torr.

[0010] Preferably, the nitrogen flow rate introduced into the carbon dioxide plasma treatment is 10,000 to 20,000 cubic centimeters per minute.

[0011] Preferably, the flow rate of argon gas introduced into the carbon dioxide plasma treatment is approximately 5000 to 10000 cubic centimeters per minute.

[0012] Preferably, the carbon dioxide plasma treatment is carried out at a flow rate of 500 to 3000 cubic centimeters per minute.

[0013] Preferably, carbon dioxide plasma treatment is performed in an environment with a temperature of 300-400°C.

[0014] Preferably, the high-frequency radio frequency of the carbon dioxide plasma treatment is about 500-2000 watts.

[0015] Preferably, the duration of the carbon dioxide plasma treatment is about 10 to 20 seconds.

[0016] This invention prevents the formation of inorganic salt stains and residual defects on the surface of the NDC thin film by adding a carbon dioxide plasma pretreatment process after NDC thin film deposition. The key feature is that the carbon dioxide plasma pretreatment is used to decompose the ammonia component on the surface of the NDC after deposition. This method does not affect the quality of the NDC thin film and can effectively remove the ammonia component, so that the etching barrier layer NDC can be removed by water washing to remove large particle defects. This avoids the yield loss caused by the inability to wash large particle defects randomly generated in the NDC process due to water stain defects. Attached Figure Description

[0017] Figure 1 This is a schematic diagram showing the wire breakage caused by particle defects when the film has undergone a water washing process;

[0018] Figure 2 This is a schematic diagram of water stain defects that occur on NDC films after a water washing process containing carbon dioxide.

[0019] Figure 3 This is a schematic diagram of the process of the present invention;

[0020] Figure 4 The NDC film produced using the method of this invention remains free of water stain defects even after repeated washing. Detailed Implementation

[0021] like Figure 3 As shown, this invention discloses a method for solving the defect of water stain residue after cleaning silicon carbonitride, comprising the following steps:

[0022] Step S1: Provide a semiconductor substrate;

[0023] Step S2: Deposit a silicon carbonitride thin film on the semiconductor substrate;

[0024] Step S3: Perform carbon dioxide plasma treatment on the semiconductor device after step S2;

[0025] In this embodiment, the carbon dioxide plasma treatment is performed at a pressure of 3-10 Torr; the nitrogen gas flow rate is 10,000-20,000 cubic centimeters per minute; the argon gas flow rate is approximately 5,000-10,000 cubic centimeters per minute; and the carbon dioxide flow rate is 500-3,000 cubic centimeters per minute. The carbon dioxide plasma treatment is performed at a temperature of 300-400°C; the high-frequency radio frequency of the carbon dioxide plasma treatment is approximately 500-2000 watts; and the treatment duration is approximately 10-20 seconds.

[0026] After using the above method, the ammonia components on the surface of the NDC were fully decomposed, ultimately achieving the effect of removing the ammonia-rich components from the NDC surface. The NDC pretreated with carbon dioxide plasma no longer exhibited water stain defects even after repeated water washing. Figure 4 As shown.

[0027] Step S4: Proceed with subsequent processes.

[0028] The method of the present invention can effectively remove ammonia components without affecting the quality of NDC film, so that the etching barrier layer NDC can be removed by water washing process to remove large particle defects, avoiding the yield loss caused by the inability to wash large particle defects randomly generated in the NDC process due to water stain defects.

Claims

1. A method for solving the water stain residue defect after silicon carbonitride (NDC) cleaning, comprising adding a carbon dioxide plasma pretreatment process after NDC thin film deposition to prevent the formation of inorganic salt water stain residue defects by the ammonia component on the NDC deposition surface and the carbon dioxide-containing water washing process, characterized in that, Includes the following steps: Step S1: Provide a semiconductor substrate; Step S2: Deposit a silicon carbonitride thin film on the semiconductor substrate; Step S3: Perform carbon dioxide plasma treatment on the semiconductor device after step S2; Step S4: Proceed with subsequent processes.

2. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, The carbon dioxide plasma treatment was carried out at a pressure of 3-10 Torr.

3. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, The nitrogen flow rate introduced into the carbon dioxide plasma treatment is 10,000 to 20,000 cubic centimeters per minute.

4. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, The flow rate of argon gas introduced into the carbon dioxide plasma treatment is 5000~10000 cubic centimeters per minute.

5. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, The carbon dioxide plasma treatment is supplied with a carbon dioxide flow rate of 500-3000 cubic centimeters per minute.

6. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, Carbon dioxide plasma treatment was carried out at a temperature of 300-400℃.

7. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, The high-frequency radio frequency of the carbon dioxide plasma treatment is 500-2000 watts.

8. The method for solving the defect of water stain residue after cleaning silicon carbonitride as described in claim 1, characterized in that, The duration of the carbon dioxide plasma treatment is 10 to 20 seconds.

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