Method and system for synchronizing control limit and equipment performance

• US 6,947,801 B2
• Filed: 08/13/2003
• Issued: 09/20/2005
• Est. Priority Date: 08/13/2003
• Status: Expired due to Fees

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Yang, Fu-Ching, Lin, Shui-Tien, Yang, Hui-Wen, Chu, Hui-Chen
• Primary Examiner(s): Picard, Leo
• Assistant Examiner(s): Garland, Steven R.
• Application Number:
  US10/639,980
• Publication Number:
  US 20050038543A1
• Time in Patent Office: 769 Days
• Field of Search: 700/108, 700/121, 700/51, 700/109, 700/174, 700/33, 700/34, 715/854, 702/81, 702/84, 702/182
• US Class Current: 700/108
• CPC Class Codes: G05B 19/41865 characterised by job scheduling, process planning, material flow
• CPC Class Codes: G05B 2219/32191 Real time statistical process monitoring
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A method system for synchronizing a control chart of an SPC system and equipment performance has a chart model (22) with new chart properties; a method for calculating a control limit based on a statistical deviation, a synchronization frequency for setting a time for reviewing new data gathered by the SPC system, and a process catalog for categorizing all control charts that control the same process step, such that the control charts are organized for assignment of the same performance based control limit calculated by using statistics formed by data for control limit values of the control charts.

Claims

1. A method of synchronizing equipment performance for a statistical process control system, comprising:

extending a chart model representation to have one or more chart properties, a control node, a control method and a process catalog;

calculating a new consistent control limit based on statistical deviation of data defined by two or more control charts directed to the same process;

assigning one or more consistent control limit to all control charts directed to the same process;

selecting a synchronization frequency and updating the control charts with new control data in response to the selected synchronization frequency;

calculating one or more new control limits based on the new control data assigning the new control limits to the control charts; and

updating all control charts directed substantially to the same process and using at least one control chart during control of a process result.

2. The method recited in claim 1, further comprising:

classifying control charts in different process catalogs corresponding to different equipment capabilities.

3. The method recited in claim 1, further comprising:

setting a higher synchronization frequency as a control limit of each of the control charts controlling a critical process result.

4. The method recited in claim 1, further comprising:

setting a lower synchronization frequency as a control limit of each of the control charts controlling a less critical process result.

5. The method recited in claim 1, further comprising:

calculating the new control limits as a function of statistical deviation of the new control data of all charts directed substantially to the same process.

6. The method recited in claim 1, further comprising:

classifying equipment capabilities for performing different processes by control charts of the different processes.

7. The method recited in claim 1, further comprising:

calculating the consistent control limit applied to all control charts of a same process catalog by calculating a statistical deviation of all the control limits for such control charts.

8. The method recited in claim 1, further comprising:

replacing a process standard deviation with a statistical deviation calculated as a control limit calculation method.

9. The method recited in claim 1, further comprising:

providing the chart model for all of the control charts of various types.

10. A system for modeling statistical process control comprising:

a computerized system having one or more control charts used during controlling and defining control limits of different process steps;

a chart model representing the control charts, the chart model providing a synchronization frequency for determining a time for redefining new control limits of the control charts, and

a Process Catalog chart property for classifying all of the control charts controlling a substantially same process step,

a Control Method chart defining a method for calculating a consistent control limit for the control charts directed substantially to substantially the same process.

11. The system recited in claim 10, further comprising:

all control charts corresponding to different equipment capabilities being classified in different processes.

12. The system recited in claim 10, wherein at least one synchronization frequency being set higher for control charts controlling critical process results.

13. The system recited in claim 10, wherein at least one synchronization frequency being set lower for control charts controlling less critical process results.

14. The system recited in claim 10, further comprising:

the new control limits being calculated as a statistical deviation formed by the new data.

15. A machine-readable medium having stored thereon a plurality of machine executable instructions, the plurality of instructions comprising instructions to:

provide a chart model representation having one or more chart properties, a control node, a control method and a process catalog;

calculate a consistent control limit based on statistical deviation of data defined by one or more control charts directed substantially to the same process;

assign one or more consistent control limit to all control charts directed substantially to the same process;

select a synchronization frequency and updating the control charts with new control data;

calculate a new control limit based on the new control data and assign the new control limits to the control charts; and

update all control charts directed substantially to the same process.

16. The machine readable medium of claim 15, further comprising classifying at least one control chart corresponding to a process equipment in a different process catalog.

17. The machine readable medium of claim 15, wherein the plurality of instructions further comprise providing a chart model for all of the control charts of various types.