Chemical-mechanical planarization controller

• US 7,437,206 B2
• Filed: 11/30/2005
• Issued: 10/14/2008
• Est. Priority Date: 12/30/2003
• Status: Expired due to Term

• Current Assignee: SC Solutions Incorporated
• Original Assignee: SC Solutions Incorporated
• Inventors: Emami-Naeini, Abbas, Roover, Dirk de, Ebert, Jon Lloyd
• Primary Examiner(s): Bahta; Kidest
• Application Number:
  US11/291,475
• Publication Number:
  US 20060106479A1
• Time in Patent Office: 1,049 Days
• Field of Search: 700/53, 700/20, 700/51, 700/19, 700/121, 700/14, 700/28, 700/108, 700/142, 700/42, 700/96, 700/123, 451/41, 451/136, 451/285, 451/398, 451/6, 451/134, 703/2, 356/630, 356/237.5
• US Class Current: 700/121
• CPC Class Codes: G05B 17/02 electric
• CPC Class Codes: G05B 2219/32342 Real time simulation
• CPC Class Codes: G05B 2219/45232 CMP chemical mechanical polishing of wafer
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

The invention provides a model-based control approach to chemical-mechanical planarization (CMP) control. The preferred embodiment comprises mathematical models of the CMP process. These models play a critical role in obtaining superior control performance. Model-based Control Design involves the construction of a dynamic mathematical model of the system to be controlled, e.g. a removal rate model of a CMP system. The model can then be evaluated via computer simulations, and validated using data from the system. The invention provides a method and apparatus that processes in-situ data from a suite of real-time sensors and produces real-time commands to multiple actuators, such as applied pressures, slurry-flow rate, and wafer/pad velocity. A key aspect of the invention is an integrated model-based pressure-temperature-velocity-slurry flow control system that includes many innovations in real-time mode identification, real-time gain estimation, and real-time control.

Claims

1. A real-time in-situ model-based chemical-mechanical planarization (CMP) controller, comprising:

a dynamic mathematical model of a CMP system to be controlled in response to in-situ data from a plurality of real-time sensors in said CMP system, said mathematical model comprising any of a physics-based model and an empirical model;

computer simulation means for evaluating said mathematical model; and

means for validating said mathematical model using any of real-time, in-situ data and ex-situ data from said CMP system.

2. The controller of claim 1, further comprising:

a reduced mathematical model for real-time in-situ CMP system control.

3. The controller of claim 1, said mathematical model comprising any of:

a real-time removal rate model of a CMP system; and

a real-time thermal model of a CMP system.

4. The controller of claim 1, wherein modifications of said CMP system can be evaluated with said mathematical model via computer simulation prior to any CMP system modifications.

5. A method for producing a real-time in-situ model-based chemical-mechanical planarization (CMP) controller, comprising the steps of:

generating a dynamic mathematical model of a CMP system to be controlled in response to in-situ data from a plurality of real-time sensors in said CMP system said mathematical model comprising any of a physics-based model and an empirical model;

evaluating said mathematical model with a computer simulation; and

validating said mathematical model using any of real-time in-situ data and ex-situ data from said CMP system.

6. The method of claim 5, further comprising the step of:

controlling said CMP system in real-time with a reduced mathematical model.

7. The method of claim 6, said mathematical model comprising any of:

a real-time removal rate model of a CMP system; and

a real-time thermal model of a CMP system.

8. The method of claim 6, further comprising the step of:

evaluating said CMP system with said mathematical model via computer simulation prior to any CMP system modifications.

9. In a model-based chemical-mechanical planarization (CMP) controller, said model comprising:

a dynamic mathematical model of a CMP system to be controlled in real-time, said mathematical model comprising any of a physics-based model, an empirical model, and any combination thereof, said mathematical model produced by open-loop and closed-loop techniques comprising use of both a computer simulation means for evaluating said mathematical model and means for validating said mathematical model using any of real-time, in-situ data and ex-situ data from said CMP system, said controller; and

a reduced mathematical model for CMP system control in response to in-situ data from a plurality of real-time sensors in said CMP system.