System for real-time control of semiconductor wafer polishing

• US 6,464,560 B2
• Filed: 07/03/2001
• Issued: 10/15/2002
• Est. Priority Date: 08/25/1993
• Status: Expired due to Term

• Current Assignee: Round Rock Research LLC
• Original Assignee: Micron Technology, Inc.
• Inventors: Sandhu, Gurtej S., Doan, Trung Tri
• Primary Examiner(s): Eley, Timothy V.
• Application Number:
  US09/898,384
• Publication Number:
  US 20010041501A1
• Time in Patent Office: 469 Days
• Field of Search: 451/5, 451/8, 451/9, 451/10, 451/53, 451/7, 451/286-290, 451/449
• US Class Current: 451/5
• CPC Class Codes: B23Q 15/013 Control or regulation of feed movement B23Q15/12 takes precedence
• CPC Class Codes: B23Q 15/12 Adaptive control, i.e. adjusting itself to have a performance which is optimum according to a preassigned criterion
• CPC Class Codes: B24B 13/015 of television picture tube viewing panels, headlight reflectors or the like
• CPC Class Codes: B24B 37/013 Devices or means for detecting lapping completion
• CPC Class Codes: B24B 37/015 Temperature control
• CPC Class Codes: B24B 37/107 in a rotary movement only, about an axis being stationary during lapping
• CPC Class Codes: B24B 37/12 Lapping plates for working plane surfaces
• CPC Class Codes: B24B 37/205 provided with a window for inspecting the surface of the work being lapped
• CPC Class Codes: B24B 49/003 involving acoustic means
• CPC Class Codes: B24B 49/02 according to the instantaneous size and required size of the workpiece acted upon, the measuring or gauging being continuous or intermittent B24B49/12 takes precedence
• CPC Class Codes: B24B 49/04 involving measurement of the workpiece at the place of grinding during grinding operation
• CPC Class Codes: B24B 49/10 involving electrical means B24B49/02, B24B49/08 take precedence
• CPC Class Codes: B24B 49/12 involving optical means
• CPC Class Codes: B24B 57/02 for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents
• CPC Class Codes: G05B 19/404 characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia G05B19/19, G05B19/41 take precedence
• CPC Class Codes: G05B 2219/34403 RTI real time, kernel, processing
• CPC Class Codes: G05B 2219/37398 Thickness
• CPC Class Codes: G05B 2219/37602 Material removal rate
• CPC Class Codes: G05B 2219/45026 Circuit board, pcb
• CPC Class Codes: G05B 2219/45199 Polish
• CPC Class Codes: G05B 2219/45232 : CMP chemical mechanical polishing of wafer
• CPC Class Codes: G05B 2219/49052 : Accessory, coolant
• CPC Class Codes: G05B 2219/49057 : Controlling temperature of workpiece, tool, probe holder

Abstract

A system for polishing a semiconductor wafer, the system comprising a wafer polishing assembly for polishing a face of a semiconductor wafer at a polishing rate and a polishing uniformity, the wafer polishing assembly including a platen subassembly defining a polishing area, and a polishing head selectively supporting a semiconductor wafer and holding a face of the semiconductor wafer in contact with the platen subassembly to polish the wafer face; and a controller selectively adjusting one of a plurality of adjustable polishing parameters during polishing of the wafer.

Claims

1. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head selectively supporting a semiconductor wafer and holding a face of the semiconductor wafer in contact with the platen subassembly to polish the wafer face;

a first heater supported by the polishing head for heating the wafer, the first heater including a heating filament supported by the polishing head; and

a second heater for heating the platen subassembly.

2. The polishing system of claim 1, wherein the polishing head includes pressure applicators for applying various localized pressures on individual regions of the semiconductor wafer to conform the wafer face to a selected contour.

3. The polishing system of claim 1, further comprising a polish control subsystem for monitoring polishing rates at various regions of the semiconductor wafer and adjusting a velocity of the platen.

4. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head selectively supporting a semiconductor wafer and holding a face of the semiconductor wafer in contact with the platen subassembly to polish the wafer face;

a first heater supported by the polishing head for heating the wafer, the first heater including a heating filament supported by the polishing head;

a second heater for heating the platen subassembly;

a controller operably coupled to the wafer polishing assembly for monitoring and managing at least one operational parameter of the wafer polishing assembly;

a processor operably coupled to the controller for determining a set of desired operational parameters based on the monitored operational parameter and outputting control information indicative of the set of desired operational parameters to the controller, the controller adjusting at least one operational parameter of the wafer polishing assembly in response to the control information from the processor to control wafer to wafer uniformity;

a fluid passage in fluid communication with the hollow interior;

a pump in fluid communication with the fluid passage and conducting fluid through the hollow interior;

the first heater including;

a fluid passage in fluid communication with the hollow interior;

a pump in fluid communication with the fluid passage and conducting fluid through the hollow interior; and

a heating element proximate the fluid passage.

5. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head selectively supporting a semiconductor wafer and holding a face of the semiconductor wafer in contact with the platen subassembly to polish the wafer face;

a first heater supported by the polishing head for heating the wafer, the first heater including a heating filament supported by the polishing head;

a second heater for heating the platen subassembly;

a controller operably coupled to the wafer polishing assembly for monitoring and managing at least one operational parameter of the wafer polishing assembly; and

a processor operably coupled to the controller for determining a set of desired operational parameters based on the monitored operational parameter and outputting control information indicative of the set of desired operational parameters to the controller, the controller adjusting at least one operational parameter of the wafer polishing assembly in response to the control information from the processor to control wafer to wafer uniformity.

6. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head configured to selectively support a workpiece and holding a face of the workpiece in contact with the platen subassembly to polish the workpiece face;

a first heater supported by the polishing head for heating the workpiece, the first heater including a heating filament supported by the polishing head; and

a second heater for heating the platen subassembly.

7. The polishing system of claim 6, wherein the polishing head includes pressure applicators for applying various localized pressures on individual regions of the workpiece to conform the workpiece face to a selected contour.

8. The polishing system of claim 6, further comprising a polish control subsystem for monitoring polishing rates at various regions of the workpiece face and adjusting a velocity of the platen.

9. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head configured to selectively support a workpiece and holding a face of the workpiece in contact with the platen subassembly to polish the workpiece face;

a first heater supported by the polishing head for heating the workpiece, the first heater including a heating filament supported by the polishing head;

a second heater for heating the platen subassembly;

a controller operably coupled to the workpiece polishing assembly for monitoring and managing at least one operational parameter of the workpiece polishing assembly;

a processor operably coupled to the controller for determining a set of desired operational parameters based on the monitored operational parameter and outputting control information indicative of the set of desired operational parameters to the controller, the controller adjusting at least one operational parameter of the workpiece polishing assembly in response to the control information from the processor to control workpiece to workpiece polishing uniformity;

a fluid passage in fluid communication with the hollow interior;

a pump in fluid communication with the fluid passage and conducting fluid through the hollow interior;

the first heater including;

a fluid passage in fluid communication with the hollow interior;

a pump in fluid communication with the fluid passage and conducting fluid through the hollow interior; and

a heating element proximate the fluid passage.

10. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head configured to selectively support a workpiece and holding a face of the workpiece in contact with the platen subassembly to polish the workpiece face;

a first heater supported by the polishing head for heating the workpiece, the first heater including a heating filament supported by the polishing head;

a second heater for heating the platen subassembly;

a controller operably coupled to the workpiece polishing assembly for monitoring and managing at least one operational parameter of the workpiece polishing assembly; and

a processor operably coupled to the controller for determining a set of desired operational parameters based on the monitored operational parameter and outputting control information indicative of the set of desired operational parameters to the controller, the controller adjusting at least one operational parameter of the workpiece polishing assembly in response to the control information from the processor to control workpiece to workpiece polishing uniformity.

11. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head selectively supporting a semiconductor wafer and holding a face of the semiconductor wafer in contact with the platen subassembly to polish the wafer face;

a polish control subsystem configured to monitor polishing rates at various regions of the semiconductor wafer and adjust a velocity of the platen;

a first heater supported by the polishing head for heating the wafer, the first heater including a heating filament supported by the polishing head; and

a second heater for heating the platen subassembly.

12. A polishing system comprising:

a platen subassembly defining a polishing area;

a polishing head configured to selectively support a workpiece and holding a face of the workpiece in contact with the platen subassembly to polish the workpiece face;

a polish control subsystem configured to monitor polishing rates at various regions of the workpiece face and adjust a velocity of the platen;

a first heater supported by the polishing head for heating the workpiece, the first heater including a heating filament supported by the polishing head; and

a second heater for heating the platen subassembly.