Process detection system for plasma process

• US 5,971,591 A
• Filed: 10/20/1997
• Issued: 10/26/1999
• Est. Priority Date: 10/20/1997
• Status: Expired due to Term

• Current Assignee: MKS Instruments Incorporated
• Original Assignee: ENI Technology, Inc. (MKS Instruments Incorporated)
• Inventors: Nasman, Kevin P., Vona, Daniel F., Gerrish, Kevin S.
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): Marc, McDieunel, Marc, McDieunel
• Application Number:
  US08/954,387
• Time in Patent Office: 736 Days
• Field of Search: 364/478.08, 364/468.28, 364/153, 438/710, 219/121.54
• US Class Current: 700/220
• 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: H01J 37/3299 Feedback systems

Abstract

Plasma process control arrangement controls a plasma generator that provides electrical power to a plasma chamber for an RF or DC plasma process. A sensor system detects operating parameters of the electrical power, including voltage and current levels. A process detection system (pds) controller has inputs coupled to the sensor system to receive the operating parameters, a programmable memory unit for storing a control program to compute an output control signal based on the operating parameters, and a control output coupled to a control input of the plasma generator. An external computer device, includes a monitor, an icon copying device for example, a mouse suitable for drag-and-drop operation, and a memory storing a suitable code-building program for generating a user-selected control program according to user-determined process requirements. Respective graphical icons are presented on the monitor and are selected and connected by use of the icon copying device to represent logic processing of the operational parameters, and the external computer device creates the corresponding user-selected control program. The user-selected control program is downloaded from the external computer device to the programmable memory of the pds controller, e.g., using standard connectors and cables.

Claims

1. Plasma process control arrangement wherein a plasma generator means provides electrical power to a plasma chamber for conducting a plasma process at a controlled level, said electrical power having detectable operating parameters including voltage and current levels, and in which a programmable detection system detects said operating parameters;

said control arrangement comprising a programmable PDS controller including input means coupled to said programmable detection system to receive said operating parameters therefrom, a programmable memory unit for storing a control program to determine an output control signal based on said operating parameters, said control program defining said detection of said operating parameters, and a control output coupled to a control input of said plasma generator means;

an external computer device including a monitor, an icon copying device, and a memory storing a suitable code-building program for generating a user-defined control program; and

means for loading the user-defined control program from the external computer device to the programmable memory of said programmable PDS controller, said user-defined control program comprising means for modifying the operation of said programmable PDS controller by defining said detection of said operating parameters according to said user-defined process requirements.

2. The plasma process control arrangement of claim 1, wherein said graphical icons include arithmetic operators.

3. The plasma process control arrangement of claim 1, wherein said graphical icons include logic operators, trigonometric operators, and signal processing operators.

4. The plasma process control arrangement of claim 1 wherein said control output includes an endpoint signal, and wherein said plasma generator means is operative to cease providing said electrical power in response to said endpoint signal.

5. The plasma process control arrangement of claim 1 wherein said external computer device comprises means for uploading performance data from the PDS controller into the computer, and said computer is operative for testing and debugging said control program while the process is being conducted.

6. The plasma process control arrangement of claim 1 comprising a sensor coupled to said generator for monitoring an additional operating parameter associated with said generator, and means connecting said sensor to an input of said PDS controller.

7. The plasma process control arrangement of claim 1 comprising a sensor coupled between said plasma generator and said chamber for monitoring a predetermined operating parameter of said plasma, and means for connecting said sensor to an input of said PDS controller.

8. The plasma process control arrangement of claim 1 wherein said icon copying device includes means for dragging and dropping said icons on said monitor.

9. RF plasma control arrangement wherein an RF plasma generator means provides RF electrical power to an RF plasma chamber for carrying out a plasma process at a controlled level, said electrical power having detectable operating parameters including voltage level, current level, and phase angle, and in which a programmable detection system detects said operating parameters;

said control arrangement comprising a programmable PDS controller including input means coupled to said programmable detection system to receive said operating parameters therefrom, a programmable memory unit for storing a control program to determine an output control signal based on said operating parameters, said control program defining said detection of said operating parameters, and a control output coupled to a control input of said plasma generator means;

an external computer device including a monitor, an icon copying device, and a memory storing a suitable code-building program for generating a user-defined control program according to user-defined process requirements, wherein respective graphical icons are presented on the monitor and are selected and connected by said program to represent logic processing of said operational parameters, and said external computer device creates the corresponding user-defined control program; and

means for loading the user-defined control program from the external computer device to the programmable memory of said programmable PDS controller said user defined control program comprising means for modifying the operation of said programmable PDS controller by defining said detection of said operating parameters according to said user-defined process requirements.

10. The RF plasma process control arrangement according to claim 9 wherein said detection system includes a voltage-current probe providing outputs signals representing RMS voltage level, RMS current level and phase angle between applied voltage and current at the plasma chamber.

11. The RF plasma process control arrangement according to claim 9 wherein said graphical icons include logic operators, trigonometric operators, and arithmetic operators.

12. The RF plasma process control arrangement according to claim 9 wherein said graphical icons include signal processing and feedback operators.

13. The RF plasma control arrangement according to claim 9 wherein said programmable memory is a non-volatile memory.

14. An RF plasma process control arrangement wherein an RF plasma generator means provides RF electrical power to an RF plasma chamber for carrying out an RF plasma process at a controlled level, said RF electrical power having detectable operating parameters including voltage level, current level, and phase angle, wherein an impedance match network is interposed between said plasma generator means and said plasma chamber, said match network including error detector means for detecting differences between electric levels and phase angles at said plasma chamber, and including at least one variable impedance and means for adjusting the value of said variable impedance, and in which a programmable detection system interposed between said match network and said chamber detects said operating parameters;

said control arrangement comprising a programmable PDS controller including input means coupled to said programmable detection system to receive said operating parameters therefrom, a programmable memory unit for storing a control program to determine an output control signal based on said operating parameters, said control program defining said detection of said operating parameters a first control output coupled to a control input of said plasma generator means;

an external computer device including a monitor, a drag-and-drop device, and a memory storing a suitable code-building program for generating a user-defined control program according to user-defined process requirements, wherein respective graphical icons are presented on the monitor and are selected and connected by use of the drag-and-drop device to represent logic processing of said operational parameters, and said external computer device creates the corresponding user-defined control program; and

means for loading the user-defined control program from the external computer device to the programmable memory of said programmable PDS controller, said user-defined control program comprising means for modifying the operation of said programmable PDS controller by defining said detection of said operating parameters according to said user-defined process requirements.

15. The RF plasma process control arrangement of claim 14, wherein said PDS controller includes a second control output coupled to the means for adjusting the value of said variable impedance.

16. An RF plasma process control arrangement wherein an RF plasma generator means provides RF electrical power to an RF plasma chamber for carrying out an RF plasma process at a controlled level, said RF electrical power having detectable operating parameters including voltage level, current level, and phase angle, wherein at least one detector is coupled with said generator and said chamber to monitor operating conditions therein, and in which a programmable detection system detects said operating parameters;

said control arrangement comprising a programmable PDS controller including first input means coupled to said programmable detection system to receive said operating parameters therefrom, second input means coupled to said at least one detector, a programmable memory unit for storing a control program to determine an output control signal based on said operating parameters, said control program defining said detection of said operating parameters, a first control output coupled to a control input of said plasma generator means;

an external computer device including a monitor, an icon copying device, and a memory storing a suitable code-building program for generating a user-defined control program according to user-defined process requirements, wherein respective graphical icons are presented on the monitor and are selected and connected by use of the icon copying device to represent logic processing of said operational parameters, and said external computer device creates the corresponding user-defined control program; and

means for loading the user-defined control program from the external computer device to the programmable memory of said programmable PDS controller, said user-defined control program comprising means of modifying the operation of said PDS programmable controller by defining said detection of said operating parameters according to said user-defined process requirements.

17. Industrial process control arrangement wherein a power generator means provides electrical power for conducting an industrial process at a controlled level, said electrical power having detectable operating parameters including voltage and current levels, and in which a detection system detects said operating parameters;

said control arrangement comprising a programmable PDS controller including input means coupled to said programmable detection system to receive said operating parameters therefrom, a programmable memory unit for storing a control program to determine an output control signal based on said operating parameters, said control program defining said detection of said operating parameters, and a control output coupled to a control input of said generator means;

an external computer device including a monitor, an icon copying device, and a memory storing a suitable code-building program for generating a user-defined control program according to user-defined process requirements; and

means for loading the user-defined control program from the external computer device to the programmable memory of said programmable PDS controller, said user-defined control program comprising means for modifying the operation of said programmable PDS controller by defining said detection of said operating parameters according to said user-defined process requirements.

18. The industrial process control arrangement of claim 17, wherein said external computer includes means for selecting any of said icons during operation of said industrial process and wherein said computer monitor indicates the process operating parameter corresponding to the selected icon.