PLASMA ETCHING METHOD CAPABLE OF DETECTING END POINT AND PLASMA ETCHING DEVICE THEREFOR

• US 20090277872A1
• Filed: 07/27/2007
• Published: 11/12/2009
• Est. Priority Date: 07/28/2006
• Status: Active Grant

• Current Assignee: SPP Technologies Co., Ltd. (Sumitomo Corporation)
• Original Assignee: Sumitomo Precision Products Company Limited (Sumitomo Corporation)
• Inventors: Yamamoto, Takashi, Nozawa, Yoshiyuki, Murakami, Shoichi, Tanaka, Masahiko
• Granted Patent: US 8,518,283 B2
• Time in Patent Office: Days
• US Class Current: 216/60
• CPC Class Codes: H01J 2237/3343 Problems associated with etching
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 22/26 Acting in response to an ongoing measurement without interruption of processing, e.g. endpoint detection, in-situ thickness measurement endpoint detection arrangements in CMP apparatus B24B37/013, in discharge apparatus H01J37/32
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

The present invention relates to a plasma etching method in which a special area for detecting an end point needs not to be set and an equipment therefor. At an etching step of forming SF₆ gas into plasma to etch an etching ground on a Si film, the step is configured by two steps of: a large-amount supply step of supplying a large amount of SF₆ gas; and a small-amount supply step of supplying a small amount of SF₆ gas. An end-point detecting processor 34 measures an emission intensity of Si or SiFx in the plasma at the small-amount supply step, and determines that an etching end point is reached when the measured emission intensity becomes equal to or less than a previously set reference value.

Claims

1. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed, wherein

at least two steps of a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented,

an emission intensity of Si or SiFx in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or less than a previously set reference value, a process is ended, determining that an etching end point is reached.

9. The plasma etching method capable of detecting an end point according to any one of claims 1 to 8, wherein at the large-amount supply step, SF₆ gas of 200 sccm or more is supplied, and at the small-amount supply step, SF₆ gas of 180 sccm or less is supplied.

2. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed, wherein

at least two steps of a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented,

an emission intensity of F in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or more than a previously set reference value, a process is ended, determining that an etching end point is reached.

3. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed, wherein

after a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate is implemented for a previously determined time, at least two steps of the large-amount supply step and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented,

an emission intensity of Si or SiFx in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or less than a previously set reference value, a process is ended, determining that an etching end point is reached.

4. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed, wherein

after a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate is implemented for a previously determined time, at least two steps of the large-amount supply step and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented,

an emission intensity of F in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or more than a previously set reference value, a process is ended, determining that an etching end point is reached.

5. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by repeatedly implementing:

an etching step of etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed; and

a passivation-layer forming step of forming a passivation-layer on a structural surface formed at the etching step by supplying passivation-layer forming gas containing CxFy gas or O₂ gas so that plasma is formed, wherein

the etching step is configured by at least two steps of;

a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate; and

a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate,

an emission intensity of Si or SiFx in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or less than a previously set reference value, a process is ended, determining that an etching end point is reached.

6. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by repeatedly implementing:

an etching step of etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed; and

a passivation-layer forming step of forming a passivation-layer on a structural surface formed at the etching step by supplying passivation-layer forming gas containing CxFy gas or O₂ gas so that plasma is formed, wherein

the etching step is configured by at least two steps of;

a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate; and

a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate,

an emission intensity of F in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or more than a previously set reference value, a process is ended, determining that an etching end point is reached.

7. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by repeatedly implementing:

an etching step of etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed and a passivation-layer forming step of forming a passivation-layer on a structural surface formed at the etching step by supplying passivation-layer forming gas containing CxFy gas or O₂ gas so that plasma is formed, wherein

the etching step and the passivation-layer forming step are repeatedly implemented for a previously determined number of times, and thereafter, the etching step is implemented by dividing into at least two steps of;

a large-amount supply step of supplying a supply amount when the previously determined number of times are repeated, i.e., a large amount of SF₆ gas for processing the silicon substrate; and

a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate,

an emission intensity of Si or SiFx in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or less than a previously set reference value, a process is ended, determining that an etching end point is reached.

8. A plasma etching method capable of detecting an end point in which a Si film of a silicon substrate including the Si film formed on a surface side and a lower layer film formed below the Si film is etched, the plasma etching method for etching the Si film by repeatedly implementing:

an etching step of etching the Si film by supplying etching gas containing SF₆ gas so that plasma is formed; and

a passivation-layer forming step of forming a passivation-layer on a structural surface formed at the etching step by supplying passivation-layer forming gas containing CxFy gas or O₂ gas so that plasma is formed, wherein

the etching step and the passivation-layer forming step are repeatedly implemented for a previously determined number of times, and thereafter, the etching step is implemented by dividing into at least two steps of;

a large-supply amount step of supplying a supply amount when the previously determined number of times are repeated, that is, a large amount of SF₆ gas for processing the silicon substrate; and

a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate,

an emission intensity of F in the plasma at the small-amount supply step is measured, and

when the measured emission intensity becomes equal to or more than a previously set reference value, a process is ended, determining that an etching end point is reached.

10. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controlling device for controlling operations of the etching-gas supply section, the plasma generating section, and the platen power-applying section such that the etching step at which the etching gas is supplied to the interior of the etching chamber, the high frequency power is applied to the coil, and the high frequency power is applied to the platen is implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on emission intensity data detected by the emission intensity detector, wherein

the controlling device is configured to control an operation of the etching-gas supply section such that at the etching step, at least two steps of a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of Si or SiFx in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or less than a previously set reference value.

18. The plasma etching equipment capable of detecting an end point according to any one of claims 10 to 17, wherein the controlling device controls an operation of the etching-gas supply section such that at the large-amount supply step, SF₆ gas of 200 sccm or more is supplied and at the small-amount supply step, SF₆ gas of 180 sccm or less is supplied.

11. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controlling device for controlling operations of the etching-gas supply section, the plasma generating section, and the platen power-applying section such that the etching step at which the etching gas is supplied to the interior of the etching chamber, the high frequency power is applied to the coil, and the high frequency power is applied to the platen is implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on emission intensity data detected by the emission intensity detector, wherein

the controlling device is configured to control an operation of the etching-gas supply section such that at the etching step, at least two steps of a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of F in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or more than a previously set reference value.

12. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controlling device for controlling operations of the etching-gas supply section, the plasma generating section, and the platen power-applying section such that the etching step at which the etching gas is supplied to the interior of the etching chamber, the high frequency power is applied to the coil, and the high frequency power is applied to the platen is implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on emission intensity data detected by the emission intensity detector, wherein

the controlling device is configured to control an operation of the etching-gas supply section such that at the etching step, a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate is implemented for a previously determined time, and thereafter, at least two steps of the large-amount supply step and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of Si or SiFx in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or less than a previously set reference value.

13. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controlling device for controlling operations of the etching-gas supply section, the plasma generating section, and the platen power-applying section such that the etching step at which the etching gas is supplied to the interior of the etching chamber, the high frequency power is applied to the coil, and the high frequency power is applied to the platen is implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on emission intensity data detected by the emission intensity detector, wherein

the controlling device is configured to control an operation of the etching-gas supply section such that at the etching step, a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate is implemented for a previously determined time, and thereafter, at least two steps of the large-amount supply step and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate are repeatedly implemented, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of F in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or more than a previously set reference value.

14. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a passivation-layer-forming-gas supply section for supplying passivation-layer forming gas containing CxFy gas or O₂ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controller for controlling operations of the etching-gas supply section, the passivation-layer-forming-gas supply section, the plasma generating section, and the platen power-applying section such that an etching step at which the etching gas is supplied to the interior of the etching chamber, supply of the passivation-layer forming gas is stopped, the high frequency power is applied to the coil, and the high frequency power is applied to the platen and a passivation-layer forming step at which the passivation-layer forming gas is supplied to the interior of the etching chamber, supply of the etching gas is stopped, the high frequency power is applied to the coil, and applying of the high frequency power to the platen is stopped are repeatedly implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on emission intensity data detected by the emission intensity detector, wherein

the controller is configured to control an operation of the etching-gas supply section such that the etching step is configured by at least two steps of a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of Si or SiFx in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or less than a previously set reference value.

15. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a passivation-layer-forming-gas supply section for supplying passivation-layer forming gas containing CxFy gas or O₂ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controller for controlling operations of the etching-gas supply section, the passivation-layer-forming-gas supply section, the plasma generating section, and the platen power-applying section such that an etching step at which the etching gas is supplied to the interior of the etching chamber, supply of the passivation-layer forming gas is stopped, the high frequency power is applied to the coil, and the high frequency power is applied to the platen and a passivation-layer forming step at which the passivation-layer forming gas is supplied to the interior of the etching chamber, supply of the etching gas is stopped, the high frequency power is applied to the coil, and applying of the high frequency power to the platen is stopped are repeatedly implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on the emission intensity detected by the emission intensity detector, wherein

the controller is configured to control an operation of the etching-gas supply section such that the etching step is configured by at least two steps of a large-amount supply step of supplying a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of F in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or more than a previously set reference value.

16. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a passivation-layer-forming-gas supply section for supplying passivation-layer forming gas containing CxFy gas or O₂ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controller for controlling operations of the etching-gas supply section, the passivation-layer-forming-gas supply section, the plasma generating section, and the platen power-applying section such that an etching step at which the etching gas is supplied to the interior of the etching chamber, supply of the passivation-layer forming gas is stopped, the high frequency power is applied to the coil, and the high frequency power is applied to the platen and a passivation-layer forming step at which the passivation-layer forming gas is supplied to the interior of the etching chamber, supply of the etching gas is stopped, the high frequency power is applied to the coil, and applying of the high frequency power to the platen is stopped are repeatedly implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on the emission intensity detected by the emission intensity detector, wherein

the controller is configured to control an operation of the etching-gas supply section such that after the etching step and the passivation-layer forming step are repeated for a previously determined number of times, the etching step is configured by at least two steps of a large-supply amount step of supplying a supply amount when the previously determined number of times are repeated, i.e., a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply a small amount of SF₆ gas for processing the silicon substrate, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of Si or SiFx in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or less than a previously set reference value.

17. A plasma etching equipment capable of detecting an end point, comprising:

an etching chamber which houses a silicon substrate including a Si film formed on a surface side and a lower layer film formed below the Si film;

a platen on which the silicon substrate is mounted, the platen being arranged at a lower position in an interior of the etching chamber;

an etching-gas supply section for supplying etching gas containing SF₆ gas to the interior of the etching chamber;

a passivation-layer-forming-gas supply section for supplying passivation-layer forming gas containing CxFy gas or O₂ gas to the interior of the etching chamber;

a depressurizing section for depressurizing the interior of the etching chamber;

a plasma generating section applying high frequency power to a coil to form the gas in the interior of the etching chamber into plasma, the plasma generating section including the coil wired at an outer periphery of the etching chamber in a manner to face the etching chamber;

a platen power-applying section for applying high frequency power to the platen; and

a controller for controlling operations of the etching-gas supply section, the passivation-layer-forming-gas supply section, the plasma generating section, and the platen power-applying section such that an etching step at which the etching gas is supplied to the interior of the etching chamber, supply of the passivation-layer forming gas is stopped, the high frequency power is applied to the coil, and the high frequency power is applied to the platen and a passivation-layer forming step at which the passivation-layer forming gas is supplied to the interior of the etching chamber, supply of the etching gas is stopped, the high frequency power is applied to the coil, and applying of the high frequency power to the platen is stopped are repeatedly implemented, the plasma etching equipment, comprising;

an emission intensity detector for detecting an emission intensity of the plasma in the interior of the etching chamber; and

an etching-end-point detecting section for detecting an end point of etching based on the emission intensity detected by the emission intensity detector, wherein

the controller is configured to control an operation of the etching-gas supply section such that after the etching step and the passivation-layer forming step are repeated for a previously determined number of times, the etching step is configured by at least two steps of a large-supply amount step of supplying a supply amount when the previously determined number of times are repeated, i.e., a large amount of SF₆ gas for processing the silicon substrate and a small-amount supply step at which a supply amount is reduced to supply and process a small amount of SF₆ gas for processing the silicon substrate, and to receive an end-point detection signal from the etching-end-point detecting section to end a series of processes, and

the etching-end-point detecting section is configured to extract an emission intensity of F in the plasma at the small-amount supply step and to transmit the end-point detection signal to the controlling device, determining that an etching end point is reached when the extracted emission intensity becomes equal to or more than a previously set reference value.