ELECTROSTATIC CHUCK, SUBSTRATE PROCESSING APPARATUS, AND SUBSTRATE HOLDING METHOD

• US 20190319555A1
• Filed: 04/12/2019
• Published: 10/17/2019
• Est. Priority Date: 04/12/2018
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: SASAKI, Yasuharu
• Granted Patent: US 11,133,759 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 21/67109 mainly by convection
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring
• CPC Class Codes: H01L 21/6833 Details of electrostatic chucks
• CPC Class Codes: H02N 13/00 Clutches or holding devices using electrostatic attraction, e.g. using Johnson-Rahbek effect

Abstract

An electrostatic chuck includes a plurality of electrodes configured to generate an electrostatic force for attracting and holding a substrate and a surface on which the substrate is to be mounted. The electrodes are arranged respectively in multiple regions radially and circumferentially defined in the electrostatic chuck. Further, a substrate processing apparatus includes an electrostatic chuck including a plurality of electrodes configured to generate an electrostatic force for attracting and holding a substrate and a surface on which the substrate is to be mounted; and a controller configured to control a timing of applying a DC voltage to each of the electrodes. Each of the electrodes generates an electrostatic force for attracting and holding the substrate by the DC voltage applied thereto, and the electrodes are arranged respectively in multiple regions radially and circumferentially defined in the electrostatic chuck.

Claims

1. An electrostatic chuck comprising:

a plurality of electrodes configured to generate an electrostatic force for attracting and holding a substrate; and

a surface on which the substrate is to be mounted,

wherein the electrodes are arranged respectively in multiple regions radially and circumferentially defined in the electrostatic chuck.

2. A substrate processing apparatus comprising:

an electrostatic chuck including a plurality of electrodes configured to generate an electrostatic force for attracting and holding a substrate and a surface on which the substrate is to be mounted; and

a controller configured to control a timing of applying a DC voltage to each of the electrodes,

wherein each of the electrodes generates an electrostatic force for attracting and holding the substrate by the DC voltage applied thereto, and

the electrodes are arranged respectively in multiple regions radially and circumferentially defined in the electrostatic chuck.

3. The substrate processing apparatus of claim 2, further comprising:

a measurement system configured to measure a distance between the electrostatic chuck and the substrate mounted on the surface of the electrostatic chuck,

wherein the measurement system measures the distance for each of the electrodes, and

the controller controls the timing of applying the DC voltage such that the DC voltage is applied to each of the electrodes in the order of the distance.

4. The substrate processing apparatus of claim 2, wherein further comprising:

a measurement system configured to measure a distance between the electrostatic chuck and the substrate mounted on the surface of the electrostatic chuck,

wherein the measurement system measures the distance for each of the electrodes, and

the controller specifies a warped state of the substrate mounted on the surface of the electrostatic chuck based on the distance, and controls the timing of applying the DC voltage such that the DC voltage is applied to each of the electrodes based on the specified warped state.

5. The substrate processing apparatus of claim 4, wherein when the warped state of the substrate is specified to a warped state in which the distance increases from a central portion toward an outer periphery of the substrate, the controller controls the timing of applying the DC voltage such that the DC voltage is initially applied to an electrode disposed at the central portion of the substrate among the electrodes, and a process, in which the DC voltage is applied to an electrode with the longest distance among one or more electrodes adjacent to the electrode(s) to which the DC voltage has already been applied, is repeated.

6. The substrate processing apparatus of claim 4, wherein when the warped state of the substrate is specified to a warped state in which the substrate is not flat and the distance does not increase from a central portion toward an outer periphery of the substrate, the controller controls the timing of applying the DC voltage such that the DC voltage is initially applied to an electrode at which the distance is the longest among the electrodes, and a process, in which the DC voltage is applied to an electrode with the longest distance among one or more electrodes adjacent to the electrode(s) to which the DC voltage has already been applied, is repeated.

7. The substrate processing apparatus of claim 5, wherein when the warped state of the substrate is specified to a warped state in which the substrate is not flat and the distance does not increase from the central portion toward the outer periphery of the substrate, the controller controls the timing of applying the DC voltage such that the DC voltage is initially applied to an electrode at which the distance is the longest among the electrodes, and a process, in which the DC voltage is applied to an electrode with the longest distance among one or more electrodes adjacent to the electrode(s) to which the DC voltage has already been applied, is repeated.

8. The substrate processing apparatus of claim 3, wherein the controller selects, among a plurality of application sequences, each of which specifies a sequence of application of the DC voltage to each of the electrodes, an application sequence corresponding to a case where the closest contact between the substrate and the electrostatic chuck is obtained, and controls the timing by using the selected application sequence.

9. The substrate processing apparatus of claim 2, wherein the controller adjusts a value of the DC voltage to be applied to each of the electrodes.

10. The substrate processing apparatus of claim 3, wherein the controller adjusts a value of the DC voltage to be applied to each of the electrodes.

11. The substrate processing apparatus of claim 4, wherein the controller adjusts a value of the DC voltage to be applied to each of the electrodes.

12. A substrate holding method for holding a substrate by using an electrostatic chuck,

wherein the electrostatic chuck includes a plurality of electrodes configured to generate an electrostatic force for attracting and holding the substrate and a surface on which the substrate is to be mounted, and

the electrodes are arranged respectively in multiple regions radially and circumferentially defined in the electrostatic chuck, and each of the electrodes generates the electrostatic force by a DC voltage applied thereto,

the method comprising:

controlling a timing of applying the DC voltage to each of the electrodes.

13. The substrate holding method of claim 12, wherein said controlling the timing includes:

measuring, for each of the electrodes, a distance between the electrostatic chuck and the substrate mounted on the surface of the electrostatic chuck; and

applying the DC voltage to each of the electrodes in the order of the distance.

14. The substrate holding method of claim 12, wherein said controlling the timing includes:

measuring, for each of the electrodes, a distance between the electrostatic chuck and the substrate mounted on the surface of the electrostatic chuck;

specifying a warped state of the substrate mounted on the surface of the electrostatic chuck based on the distance; and

controlling the timing of applying the DC voltage to each of the electrodes based on the warped state.

15. The substrate holding method of claim 14, wherein when the warped state of the substrate is specified to a warped state in which the distance increases from a central portion toward an outer periphery of the substrate in said specifying the warped state, said controlling the timing of applying the DC voltage to each of the electrodes based on the warped state includes:

initially applying the DC voltage to an electrode disposed at the central portion of the surface among the electrodes; and

repeating a process in which, the DC voltage is applied to an electrode with the longest distance among one or more electrodes adjacent to the electrode(s) to which the DC voltage has already been applied.

16. The substrate holding method of claim 14, wherein when the warped state of the substrate is specified to a warped state in which the substrate is not flat and the distance does not increase from a central portion toward an outer periphery of the substrate in said specifying the warped state, said controlling the timing of applying a DC voltage to each of the electrodes based on the warped state includes:

initially applying the DC voltage to an electrode at which the distance is the longest among the electrodes; and

repeating a process in which, the DC voltage is applied to an electrode with the longest distance among one or more electrodes adjacent to the electrode(s) to which the DC voltage has already been applied.

17. The substrate holding method of claim 13, wherein in said controlling the timing, among a plurality of application sequences each of which specifies a sequence of application of the DC voltage to each of the electrodes, an application sequence corresponding to a case where the closest contact between the substrate and the electrostatic chuck is obtained is selected, and the timing is controlled by using the selected application sequence.

18. The substrate holding method of claim 12, in said controlling the timing, a value of the DC voltage applied to each of the electrodes is adjusted.

19. The substrate holding method of claim 13, in said controlling the timing, a value of the DC voltage applied to each of the electrodes is adjusted.

20. The substrate holding method of claim 14, in said controlling the timing, a value of the DC voltage applied to each of the electrodes is adjusted.