Plasma processing apparatus and control method thereof

• US 20050205208A1
• Filed: 02/18/2005
• Published: 09/22/2005
• Est. Priority Date: 02/20/2004
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Kato, Hideo, Tsuchiya, Hiroshi, Ohtani, Ryuji, Higashiura, Tsutomu, Sagae, Naoto
• Granted Patent: US 7,682,982 B2
• Time in Patent Office: Days
• US Class Current: 156/345.280
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge

Abstract

There is provided a plasma processing apparatus includes a lower electrode in a processing chamber on which a object to be processed is mounted; an upper electrode confronting the lower electrode; a first and a second high-frequency power supply for applying high-frequency powers respectively to the upper and the lower electrode; and an output controller for raising each of outputs from the high-frequency power supplies at least three times in a stepwise manner up to each of set levels for processing the object to be processed. The output controller adjusts each of rising times of the outputs from the high-frequency power supplies so that an output of the second high-frequency power supply is raised earlier than an output of the first high-frequency power supply while the outputs from the high-frequency power supplies are raised up to the set levels in a stepwise manner.

Claims

1. A plasma processing apparatus, comprising:

a lower electrode disposed in a processing chamber, capable of mounting an object to be processed thereon;

an upper electrode disposed in the chamber to face the lower electrode;

a first high-frequency power supply for applying high-frequency power to the upper electrode;

a second high-frequency power supply for applying high-frequency power to the lower electrode;

an output controller for raising stepwise, respective outputs of the high-frequency power supplies up to respective set levels for processing the object to be processed in at least three steps,

wherein the output controller regulates raise timings of the outputs of the respective high-frequency power supplies so that raising the output of the second high-frequency power supply is followed by raising the output of the first high-frequency power supply, while the outputs of the high-frequency power supplies are raised stepwise up to the respective set levels.

3. The plasma processing apparatus of claim 1, wherein the output controller regulates the outputs of the respective high-frequency power supplies so that the outputs right before reaching the respective set levels are within 25% and 50% of the set levels.

4. The plasma processing apparatus of claim 3, wherein the output controller regulates the outputs of the respective high-frequency power supplies so that first outputs are equal to or above levels at which plasma can be ignited and not more than 25% of the respective set levels.

5. The plasma processing apparatus of claim 1, wherein the output controller regulates the outputs of the respective high-frequency power supplies so that, while keeping the output of one high-frequency power supply constant, the output of the other high-frequency power supply is raised.

6. The plasma processing apparatus of claim 1, wherein the output controller regulates the outputs of the respective high-frequency power supplies so that differences between the respective outputs fall within a certain range.

2. A plasma processing apparatus, comprising:

a lower electrode disposed in a processing chamber, capable of mounting an object to be processed thereon;

an upper electrode disposed in the chamber to face the lower electrode;

a first and a second high-frequency power supply for applying high-frequency power to the lower electrode;

an output controller for raising stepwise, respective outputs of the high-frequency power supplies up to respective set levels for processing the object to be processed in at least three steps,

wherein the output controller regulates raise timings of the outputs of the respective high-frequency power supplies so that raising the output of the second high-frequency power supply is followed by raising the output of the first high-frequency power supply, while the outputs of the high-frequency power supplies are raised stepwise up to the respective set levels.

7. A plasma processing apparatus, comprising:

a lower electrode disposed in a processing chamber, capable of mounting an object to be processed thereon;

an upper electrode disposed in the chamber to face the lower electrode;

a first and a second high-frequency power supply for applying high-frequency power to the electrodes;

an output controller for continuously raising respective outputs of the high-frequency power supplies to respective set levels for processing the object to be processed or for raising the respective outputs of the high-frequency power supplies to the respective set levels stepwise during a certain interval and continuously during the rest.

8. The plasma processing apparatus of claim 7, wherein the output controller regulates the outputs of the respective high-frequency power supplies so that ratios between the respective outputs remain constant or so that slopes of the outputs of the respective power supplies are identical as they go up.

9. The plasma processing apparatus of claim 7, wherein the output controller regulates the respective outputs of the high-frequency power supplies so that the respective outputs are raised to the respective set levels stepwise during a certain interval and continuously during the rest.

10. The plasma processing apparatus of claim 9, wherein the interval during which the respective outputs are raised stepwise is an initial stage during which plasma is ignited.

11. The plasma processing apparatus of claim 7, wherein the output controller regulates the outputs of the respective high-frequency power supplies so that the output of one high-frequency power supply goes up stepwise while the other output goes up continuously.

12. The plasma processing apparatus of claim 11, wherein the output of the first high-frequency power supply is applied to the upper electrode and the output of the second high-frequency power supply is applied to the lower electrode, the output controller regulating the respective outputs so that the output of the first high-frequency power supply goes up stepwise and the output of the second high-frequency power supply goes up continuously.

13. A method for controlling a plasma processing apparatus including a lower electrode in a processing chamber on which an object to be processed is mounted, an upper electrode disposed in the chamber to face the lower electrode, a first high-frequency power supply for applying a high-frequency power to the upper electrode and a second high-frequency power supply for applying a high-frequency power to the lower electrode, comprising the steps of:

raising respective outputs of the high-frequency power supplies at least three times stepwise to reach respective set levels for processing the object to be processed; and

controlling respective raise timings of the outputs of the high-frequency power supplies so that raising the output of the second high-frequency power supply is followed by raising the output of the first high-frequency power supply while the respective outputs of the high-frequency power supplies are raised to the respective set levels.

15. The method of claim 13, wherein the respective outputs of the high-frequency power supplies are regulated so that the outputs right before reaching the respective set levels are within 25% and 50% of the set levels.

16. The method of claim 15, wherein the outputs of the respective high-frequency power supplies are regulated so that first outputs are equal to or above levels at which plasma can be ignited and not more than 25% of the respective set levels.

17. The method of claim 13, wherein the outputs of the respective high-frequency power supplies are regulated so that, while keeping the output of one high-frequency power supply constant, the output of the other high-frequency power supply is raised.

18. The method of claim 13, wherein the outputs of the respective high-frequency power supplies are regulated so that differences between the respective outputs fall within a certain range.

14. A method for controlling a plasma processing apparatus including a lower electrode in a processing chamber on which an object to be processed is mounted, an upper electrode disposed to face the lower electrode and a first and a second high-frequency power supply for applying high-frequency powers to the lower electrode, comprising the steps of:

raising respective outputs of the high-frequency power supplies at least three times stepwise to reach respective set levels for processing the object to be processed; and

controlling respective raise timings of the outputs of the high-frequency power supplies so that raising the output of the second high-frequency power supply is followed by raising the output of the first high-frequency power supply while the respective outputs of the high-frequency power supplies are raised to the respective set levels.

19. A method for controlling a plasma processing apparatus including a lower electrode in a processing chamber on which an object to be processed is mounted, an upper electrode disposed in the chamber to face the lower electrode and a first and a second high-frequency power supply for applying high-frequency powers to the electrodes, comprising the step of continuously raising respective outputs of the high-frequency power supplies to respective set levels for processing the object to be processed or for raising the respective outputs of the high-frequency power supplies to the respective set levels stepwise during a certain interval and continuously during the rest.

20. The method of claim 19, wherein the outputs of the respective high-frequency power supplies are regulated so that ratios between the respective outputs remain constant or so that slopes of the outputs of the respective power supplies are identical as they go up.

21. The method of claim 19, wherein the respective outputs of the high-frequency power supplies are regulated so that the respective outputs are raised to the respective set levels stepwise during a certain interval and continuously during the rest

22. The method of claim 21, wherein the interval during which the respective outputs are raised stepwise is an initial stage during which plasma is ignited.

23. The method of claim 19, wherein the outputs from the respective high-frequency power supplies are regulated so that the output of one high-frequency power supply goes up stepwise while the other output goes up continuously.

24. The method of claim 23, wherein the output of the first high-frequency power supply is applied to the upper electrode and the output of the second high-frequency power supply is applied to the lower electrode, the respective outputs are regulated so that the output of the first high-frequency power supply goes up stepwise and the output of the second high-frequency power supply goes up continuously.