Process control system

• US 6,512,985 B1
• Filed: 05/19/2000
• Issued: 01/28/2003
• Est. Priority Date: 05/19/2000
• Status: Expired due to Term

• Current Assignee: Bell Semiconductor, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Whitefield, Bruce J., Knoch, John A., Rehani, Manu
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): Cherry, Stephen J.
• Application Number:
  US09/574,365
• Time in Patent Office: 984 Days
• Field of Search: 702/81, 702/82, 702/83, 702/84, 700/17, 324/158.1, 209/571
• US Class Current: 702/81
• CPC Class Codes: G05B 19/41875 characterised by quality surveillance of production
• CPC Class Codes: G05B 2219/32201 Build statistical model of past normal proces, compare with actual process
• CPC Class Codes: G05B 2219/32212 If parameter out of tolerance reject product
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A computerized system for analyzing information associated with a process unit. A database contains historical information relating to previously compiled information. A secure input receives criteria from a restricted source. A computer mathematically determines a limit based upon the criteria. An open input receives the information associated with the process unit from multiple test locations. A compiler selectively adds to the database of historical information the information. The computer also selects at least a portion of the information based upon selection criteria. In addition, the computer manipulates the selected information based upon manipulation criteria. The manipulated information is compared against the limit. An output indicates a first disposition of the process unit when the manipulated information violates the limit. The output indicates a second disposition of the process unit when the manipulated information does not violate the limit.

Claims

1. A computerized system for analyzing property information associated with a process characteristic of a process unit, the system comprising:

a database of historical information relating to previously compiled property information associated with the process characteristic,

secure input means for receiving limit criteria, compilation criteria, selection criteria, manipulation criteria, and disposition criteria from a restricted source,

computing means for mathematically determining a limit based upon the limit criteria,

open input means for receiving the property information associated with the process characteristic of the process unit from multiple test locations,

compilation means for selectively adding to the database of historical information the property information associated with the process characteristic of the process unit received from the multiple test locations based upon the compilation criteria,

the computing means further for selecting at least a portion of the property information associated with the process characteristic of the process unit based upon the selection criteria,

the computing means further for manipulating the selected property information associated with the process characteristic of the process unit based upon the manipulation criteria,

comparison means for comparing the manipulated property information associated with the process characteristic of the process unit against the limit, and

output means for indicating a first disposition of the process unit based on the disposition criteria when the manipulated property information associated with the process characteristic of the process unit violates the limit, and for indicating a second disposition of the process unit based on the disposition criteria when the manipulated property information associated with the process characteristic does not violate the limit.

2. The computerized system of claim 1 wherein the limit further comprises a scrap limit, the first disposition is to scrap the process unit, and the second disposition is to pass the process unit.

3. The computerized system of claim 1 wherein the limit further comprises a learning limit, the first disposition is to gather additional property information associated with the process characteristic of the process unit, and the second disposition is to pass the process unit.

4. The computerized system of claim 1 wherein the limit further comprises a scrap limit and a learning limit,

the first disposition in regard to the scrap limit is to scrap the process unit, and the second disposition in regard to the scrap limit is to compare the manipulated property information associated with the process characteristic of the process unit against the learning limit, and

the first disposition in regard to the learning limit is to gather additional property information associated with the process characteristic of the process unit, and the second disposition in regard to the learning limit is to pass the process unit.

5. The computerized system of claim 1 wherein the output means further indicate specific tests to be accomplished on the process unit to gather additional property information associated with the process characteristic of the process unit when the manipulated property information associated with the process characteristic violates the limit and the first disposition of the process unit is indicated.

6. The computerized system of claim 1 further comprising:

the computing means for mathematically determining a plurality of limits based upon the limit criteria, for making a plurality of selections from the property information associated with the process characteristic of the process unit based upon the selection criteria, and independently manipulating the plurality of selections based upon the manipulation criteria, and

the comparison means for independently comparing the plurality of manipulated selections against the plurality of limits, and

the output means for indicating a first disposition of the process unit and a second disposition of the process unit for each independent comparison of the plurality of manipulated selections against the plurality of limits.

7. The computerized system of claim 1 further comprising:

the computing means for mathematically determining a plurality of limits based upon the limit criteria, for making a plurality of selections from the property information associated with the process characteristic of the process unit based upon the selection criteria, and independently manipulating the plurality of s elections based upon the manipulation criteria, and

the comparison means for independently comparing the plurality of manipulated selections against the plurality of limits, and

the output means for selectively indicating a first disposition of the process unit and a second disposition of the process unit based upon a pattern of the comparison of the plurality of manipulated selections against the plurality of limits.

8. The computerized system of claim 1 wherein the manipulation criteria further comprise at least one of property information mean, property information standard deviation, property information range, and property information running range.

9. The computerized system of claim 1 further comprising reporting means for displaying trend analysis of the historical information and the property information.

10. The computerized system of claim 1 wherein the restricted source further comprises an engineer responsible for a process that governs the process characteristic.

11. The computerized system of claim 1 wherein the compilation criteria further comprises accepting the property information for compilation when artifacts do not exist within the property information and rejecting the property information for compilation when artifacts exist within the property information.

12. The computerized system of claim 1 wherein the process characteristic further comprises at least one of a particle count measurement, a particle distribution measurement, a particle size measurement, and a defect type and classification.

13. The computerized system of claim 1 further comprising test instruments disposed at the multiple test locations, the test instruments for sensing the property information associated with the process characteristic of the process unit and providing the property information to the open input means.

14. A method for selecting a disposition of a process unit, the method comprising:

compiling a database of historical information relating to previously sensed property information associated with a process characteristic of the process unit,

determining a limit based upon limit criteria,

sensing property information associated with the process characteristic of the process unit,

selectively adding to the database of historical information the sensed property information associated with the process characteristic of the process unit based upon compilation criteria,

selecting at least a portion of the sensed property information associated with the process characteristic of the process unit based upon selection criteria,

manipulating the selected property information associated with the process characteristic of the process unit based upon manipulation criteria,

comparing the manipulated property information associated with the process characteristic of the process unit against the limit,

selecting a first disposition of the process unit when the manipulated property information associated with the process characteristic of the process unit violates the limit, and

selecting a second disposition of the process unit when the manipulated property information associated with the process characteristic of the process unit does not violate the limit.

15. The method of claim 14 wherein the step of determining a limit further comprises mathematically manipulating the database of historical information based on the limit criteria to determine the limit.

16. The method of claim 14 wherein the limit is a scrap limit and the step of selecting the first disposition further comprises scrapping the process unit and the step of selecting the second disposition further comprises passing the process unit.

17. The method of claim 14 wherein the limit is a learning limit and the step of selecting the first disposition further comprises gathering additional property information associated with the process characteristic of the process unit and the step of selecting the second disposition further comprises passing the process unit.

18. The method of claim 14 wherein the limit is a learning limit and the step of selecting the first disposition further comprises indicating specific tests to be accomplished on the process unit to gather additional property information associated with the process characteristic of the process unit.

19. The method of claim 14 wherein the step of mathematically manipulating the database of historical information further comprises determining a plurality of limits based upon the limit criteria,

the step of selecting at least a portion of the sensed property information further comprises making a plurality of selections from the sensed property information associated with the process characteristic of the process unit based upon the selection criteria,

the step of manipulating the selected property information further comprises independently manipulating the plurality of selections based upon manipulation criteria,

the step of comparing the manipulated property information further comprises independently comparing the plurality of manipulated selections against the plurality of limits, and

the steps of selecting the first disposition and the second disposition of the process unit further comprise selecting the first disposition and alternately the second disposition of the process unit for each independent comparison of the plurality of manipulated selections against the plurality of limits.

20. A computerized system for determining the capability of a process to produce process units having a process characteristic that does not violate a limit, the system comprising:

secure input means for receiving limit criteria, compilation criteria, selection criteria, and capability criteria from a restricted source,

a test instrument for sensing property information associated with the process characteristic of the process unit,

open input means for receiving the sensed property information associated with the process characteristic of the process unit from the test instrument,

a database of historical information relating to previously compiled property information associated with the process characteristic,

compilation means for selectively adding to the database of historical information the property information associated with the process characteristic of the process unit received from the test instrument based upon the compilation criteria,

computing means for,

selecting at least a portion of the historical information associated with the process characteristic of the process unit based upon the selection criteria,

mathematically manipulating the selected historical information associated with the process characteristic of the process unit to determine a capability parameter based upon the capability criteria, and

mathematically determining a limit based upon the limit criteria,

comparison means for comparing the capability parameter against the limit, and

output means for indicating a first process capability indicator when the capability parameter violates the limit, and for indicating a second process capability indicator when the capability parameter does not violate the limit.