Preventive Maintenance Method for Chamber of Metal Etching Machine

Abstract

The present application discloses a preventive maintenance method for a chamber of a metal etching machine. An optimized burning cleaning recipe is added before the chamber is opened, and metal substances remaining on the surface of an electrostatic chuck are removed by adopting a cleaning/pumping down multi-step alternate method. Before the chamber is opened for preventive maintenance, the phenomenon of metal particles remaining on the surface of the electrostatic chuck can be significantly improved, thus solving the downtime problem caused by abnormal backside helium and ensuring the stability of mass production.

Claims

1. A preventive maintenance method for a chamber of a metal etching machine, wherein the preventive maintenance method for the chamber of the metal etching machine comprises the following steps: S0: the chamber of the metal etching machine entering mean time between cleans; S1: before the chamber of the metal etching machine is opened, cleaning an electrostatic chuck in the chamber and a chamber wall by using an O.sub.2 burning cleaning method; S2: exhausting and pumping down the chamber; S3: cleaning the electrostatic chuck in the chamber and the chamber wall by using an NF.sub.3/Cl.sub.2 burning cleaning method; S4: exhausting and pumping down the chamber; and S5: opening the chamber of the metal etching machine for preventative maintenance.

2. The preventive maintenance method for the chamber of the metal etching machine according to claim 1, wherein, after step S5, a step S6 of cleaning the electrostatic chuck in the chamber and the chamber wall by using the O.sub.2 burning cleaning method is performed.

3. The preventive maintenance method for the chamber of the metal etching machine according to claim 1, wherein when the chamber is pumped down from an exhaust port, the opening of an exhaust valve at the exhaust port of the chamber is maximized.

4. The preventive maintenance method for the chamber of the metal etching machine according to claim 1, wherein step S1 comprises the following steps: S11: injecting O.sub.2 from a gas inlet into the chamber at a flow greater than a first flow to clean the electrostatic chuck in a mode that an internal pressure of the chamber is lower than a first pressure by using the O.sub.2 burning cleaning method; and S12: keeping a flow of O.sub.2 injected from the gas inlet into the chamber unchanged to clean the electrostatic chuck and the chamber wall in a mode that the internal pressure of the chamber is higher than a second pressure by using the O.sub.2 burning cleaning method, the second pressure being higher than the first pressure.

5. The preventive maintenance method for the chamber of the metal etching machine according to claim 4, wherein the first pressure is 8.6 mt/m.sup.2, the second pressure is 43 mt/m.sup.2, and the first flow is 200 sccm.

6. The preventive maintenance method for the chamber of the metal etching machine according to claim 4, wherein step S3 comprises the following steps: S31: injecting NF.sub.3 from the gas inlet into the chamber at a flow greater than a second flow, injecting Cl.sub.2 at a flow greater than a third flow and injecting SF.sub.6 at a flow smaller than a fourth flow to clean the electrostatic chuck in the mode that the internal pressure of the chamber is lower than the first pressure by adopting the NF.sub.3/Cl.sub.2 burning cleaning method, the second flow being greater than the third flow greater than the fourth flow; and S32: keeping a flow of NF.sub.3, Cl.sub.2, and SF.sub.6 injected form the gas inlet into the chamber unchanged, simultaneously injecting O.sub.2 from the gas inlet into the chamber at a flow smaller than a fifth flow and injecting H.sub.2 at a flow smaller than a sixth flow to clean the electrostatic chuck and the chamber wall in the mode that the internal pressure of the chamber is higher than the second pressure by using the NF.sub.3/Cl.sub.2 burning cleaning method, the second flow being greater than the fifth flow greater than the sixth flow.

7. The preventive maintenance method for the chamber of the metal etching machine according to claim 6, wherein the second flow is equal to the first flow.

8. The preventive maintenance method for the chamber of the metal etching machine according to claim 6, wherein the second flow is 200 sccm, the third flow is 50 sccm, the fourth flow is 10 sccm, the fifth flow is 50 sccm, and the sixth flow is 20 sccm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly describe the technical solution of the present application, the drawings required for the present application will be briefly introduced below. It is obvious that the drawings in the following description are only some embodiments of the present application. Those skilled in the art may obtain other drawings based on these drawings without contributing any inventive labor.

[0029] FIG. 1 illustrates a schematic diagram of a recovery process of existing preventative maintenance.

[0030] FIG. 2 illustrates a schematic diagram of particles remaining on a surface of an electrostatic chuck in existing preventative maintenance.

[0031] FIG. 3 illustrates a flowchart of a preventive maintenance method for a chamber of a metal etching machine according to an embodiment of the present application.

[0032] FIG. 4 illustrates a schematic diagram of an improved situation of particles remaining on a surface of an electrostatic chuck in a preventive maintenance method for a chamber of a metal etching machine according to an embodiment of the present application.

DETAILED DESCRIPTION

[0033] The technical solution of the present application will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, not all of them. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without contributing any inventive labor still fall within the scope of protection of the present application.

Embodiment 1

[0034] Referring to FIG. 3, a Preventive Maintenance (PM) method for a chamber of a metal etching machine, which includes the following steps:

[0035] S0: the chamber of the metal etching machine entering Mean Time Between Clean (MTBC);

[0036] S1: before the etching chamber of the metal etching machine is opened, cleaning an ElectroStatic Chuck (ESC) in the chamber and a chamber wall by using an O.sub.2 burning cleaning method;

[0037] S2: exhausting and pumping down the chamber to remove organic polymers in the chamber;

[0038] S3: cleaning the ESC in the chamber and the chamber wall by using an NF.sub.3/Cl.sub.2 burning cleaning method;

[0039] S4: exhausting and pumping down the chamber to remove metal polymers in the chamber;

[0040] S5: opening the etching chamber of the metal etching machine for PM.

[0041] Further, after step S5, step S6 of cleaning the ESC in the chamber and the chamber wall by using the O.sub.2 burning cleaning method is performed.

[0042] Further, when the chamber is pumped down from an exhaust port, the opening of an exhaust valve at the exhaust port of the chamber is maximized.

[0043] In the preventative maintenance method for the chamber of the metal etching machine according to embodiment 1, an optimized burning cleaning recipe is added before the chamber is opened, and metal substances (such as WxFy/AlxFy) remaining on the surface of the ESC are removed by adopting a cleaning/pumping down multi-step alternate method. As illustrated in FIG. 4, before the chamber is opened for PM, the phenomenon of metal particles remaining on the surface of the ESC can be significantly improved, thus solving the downtime problem caused by abnormal backside helium and ensuring the stability of mass production. This method is applicable to the field of dry etching process technology of all semiconductor factories.

Embodiment 2

[0044] Based on the preventive maintenance method for the chamber of the metal etching machine according to embodiment 1, step S1 includes the following steps:

[0045] S11: injecting O.sub.2 from a gas inlet into the chamber at a flow greater than a first flow to clean the ESC in a mode that the internal pressure of the chamber is lower than a first pressure by using the O.sub.2 burning cleaning method;

[0046] S12: keeping the flow of O.sub.2 injected form the gas inlet into the chamber unchanged to clean the ESC and the chamber wall in a mode that the internal pressure of the chamber is higher than a second pressure by using the O.sub.2 burning cleaning method, the second pressure being higher than the first pressure.

[0047] Further, the first pressure is 8.6 mt/m.sup.2; the second pressure is 43 mt/m.sup.2; the first flow is 200 sccm.

Embodiment 3

[0048] Based on the preventive maintenance method for the chamber of the metal etching machine according to embodiment 2, step S3 includes the following steps:

[0049] S31: injecting NF.sub.3 from the gas inlet into the chamber at a flow greater than a second flow, injecting Cl.sub.2 at a flow greater than a third flow and injecting SF.sub.6 at a flow smaller than a fourth flow to clean the ESC in the mode that the internal pressure of the chamber is lower than the first pressure by adopting the NF.sub.3/Cl.sub.2 burning cleaning method, the second flow being greater than the third flow greater than the fourth flow;

[0050] S32: keeping the flow of NF.sub.3, Cl.sub.2 and SF.sub.6 injected form the gas inlet into the chamber unchanged, simultaneously injecting O.sub.2 from the gas inlet into the chamber at a flow smaller than a fifth flow and injecting H.sub.2 at a flow smaller than a sixth flow to clean the ESC and the chamber wall in the mode that the internal pressure of the chamber is higher than the second pressure by using the NF.sub.3/Cl.sub.2 burning cleaning method, the second flow being greater than the fifth flow greater than the sixth flow.

[0051] Further, the second flow is equal to the first flow.

[0052] Further, the second flow is 200 sccm, the third flow is 50 sccm, the fourth flow is 10 sccm, the fifth flow is 50 sccm and the sixth flow is 20 sccm.

[0053] In the preventative maintenance method for the chamber of the metal etching machine according to embodiment 3, when using the NF.sub.3/Cl.sub.2 burning cleaning method for ESC cleaning and chamber wall cleaning in the chamber, firstly NF.sub.3, Cl.sub.2 and SF.sub.6 are injected in the low pressure mode for ESC cleaning, then the flow of NF.sub.3, Cl.sub.2 and SF.sub.6 are kept unchanged, a small amount of O.sub.2 and H.sub.2 are added, and then the mode is switched to the high pressure mode for chamber wall cleaning. Not only the cleaning effect is good, but also the chamber can be protected.

[0054] What are described above are only preferred embodiments of the present application, which, however, are not used to limit the present application. Any modification, equivalent replacement, improvement and the like made within the essence and principle of the present application shall be included in the scope of protection of the present application.