Fuzzy control method for adjusting a semiconductor machine

• US 8,010,212 B2
• Filed: 09/30/2008
• Issued: 08/30/2011
• Est. Priority Date: 04/09/2008
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Inotera Memories Incorporated (Micron Technology, Inc.)
• Inventors: Chen, Chun Chi, Lee, Yi Feng, Lin, Tzu-Cheng, Tian, Yun-Zong
• Primary Examiner(s): Chaki; Kakali
• Assistant Examiner(s): Booker; Kelvin
• Application Number:
  US12/241,568
• Publication Number:
  US 20090259332A1
• Time in Patent Office: 1,064 Days
• Field of Search: 700/110, 700/109, 700/117, 700/121, 700/51, 700/53, 700/50, 700 28- 33, 700 44- 48, 706/900, 706/3, 706/4, 706/9, 706/23, 706/904
• US Class Current: 700/50
• CPC Class Codes: G05B 13/0275 using fuzzy logic only
• CPC Class Codes: G06N 20/00 Machine learning
• CPC Class Codes: Y10S 706/904 Manufacturing or machine, e.g. agricultural machinery, machine tool

Abstract

A method of fuzzy control for adjusting a semiconductor machine comprising: providing measurement values from first the “parameter of a pre-semiconductor manufacturing process”, second the “parameter of the semiconductor manufacturing process”, and third the “operation parameter of the semiconductor manufacturing process”; performing a fuzzy control to define two inputs and one output corresponding to the measurement values, wherein the difference between the first and third values, and the difference between the second and third values, forms the two inputs, then from the two inputs one target output is calculated by fuzzy inference; finally, determining if the target output is in or out of an acceptable range. Whereby the target output is the “machine control parameter of the semiconductor manufacturing process” and when within an acceptable range is used for adjusting the semiconductor machine.

Claims

1. A fuzzy control method for adjusting a semiconductor machine, applied to the semiconductor machine in a semiconductor manufacturing process, the method comprising:

providing a machine measurement parameter of a pre-semiconductor manufacturing process, a machine measurement parameter of the semiconductor manufacturing process, and a machine operation parameter of the semiconductor manufacturing process;

determining a difference between the machine measurement parameter of the pre-semiconductor manufacturing process and the machine operation parameter, and determining another difference between the machine measurement parameter of the semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process;

executing a fuzzy deciding operation on basis of a first parameter input value and a second parameter input value, and selecting a machine adjusting level of the semiconductor manufacturing process accordingly, wherein the difference between the machine measurement parameter of the pre-semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process is defined as the first parameter input value, the difference between the machine measurement parameter of the semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process is defined as the second parameter input value, defining a parameter output value and setting a machine control parameter of the semiconductor manufacturing process to the parameter output value; and

determining whether the machine control parameter of the semiconductor manufacturing process surpasses an acceptable range, wherein, when the machine control parameter of the semiconductor manufacturing process surpasses the acceptable range, repeating the above steps;

otherwise utilizing the machine control parameter of the semiconductor manufacturing process for adjusting the machine.

2. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 1, wherein the pre-semiconductor manufacturing process and the semiconductor manufacturing process are a wafer cleaning process, a photo process, a coating process, or an etching process.

3. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 1, wherein the machine measurement parameter and the machine operation parameter are a wafer cleaning parameter, an exposure parameter, a coating parameter, or an etching parameter.

4. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 1, wherein the machine adjusting level is a small adjusting level, a medium adjusting level, or a big adjusting level.

5. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 1, wherein the fuzzy deciding operation comprises:

performing a fuzzy operation to define a first membership function value corresponding to the first and the second parameter input values and a second membership function value corresponding to the parameter output value;

building a fuzzy rule, wherein a condition set of the fuzzy rule is the first membership function value;

performing a deciding operation, wherein a result of the deciding operation is the second membership function value; and

performing a de-fuzzy operation for the second membership function value.

6. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 5, wherein the first membership function value and the second membership function value are a triangle-type membership function value.

7. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 5, wherein the fuzzy rule is an IF-THEN type.

8. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 5, wherein the fuzzy operation is an area method, a gravity center method, or a height method.

9. A fuzzy control method for adjusting a semiconductor machine, applied to a semiconductor machine in a semiconductor manufacturing process, the method comprising:

providing a machine measurement parameter of a pre-semiconductor manufacturing process, a machine measurement parameter of the semiconductor manufacturing process, and a machine operation parameter of the semiconductor manufacturing process;

determining a difference between the machine measurement parameter of the pre-semiconductor manufacturing process and the machine operation parameter, and determining another difference between the machine measurement parameter of the semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process;

selecting a machine adjusting level of the semiconductor manufacturing process;

performing a fuzzy operation on basis of the difference between the machine measurement parameter of the pre-semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process defined as a first parameter input value, and the difference between the machine measurement parameter of the semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process defined as a second parameter input value, defining a parameter output value, and defining a first membership function value corresponding to the first and the second parameter input values and a second membership function value corresponding to the parameter output value;

building establishing a fuzzy rule, wherein a condition set of the fuzzy rule is the first membership function value;

performing a deciding operation, wherein a result of the deciding operation is the second membership function value;

performing a de-fuzzy operation for the second membership function value to obtain a machine control parameter of the semiconductor manufacturing process; and

determining whether the machine control parameter of the semiconductor manufacturing process surpasses an acceptable range, wherein, when the machine control parameter of the semiconductor manufacturing process surpasses the acceptable range, returning to the step of establishing the fuzzy rule;

otherwise utilizing the machine control parameter of the semiconductor manufacturing process for adjusting the machine.

10. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 9, wherein the pre-semiconductor manufacturing process and the semiconductor manufacturing process are a wafer cleaning process, a photo process, a coating process, or an etching process.

11. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 9, wherein the machine measurement parameter and the machine operation parameter are a wafer cleaning parameter, an exposure parameter, a coating parameter, or an etching parameter.

12. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 9, wherein the machine adjusting level is a small adjusting level, a medium adjusting level, or a big adjusting level.

13. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 9, wherein both the first membership function value and a second membership function value are a triangle-type membership function value.

14. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 9, wherein the fuzzy rule is an IF-THEN type.

15. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 9, wherein the fuzzy operation is an area method, a gravity center method, or a height method.

16. A fuzzy control method for adjusting a semiconductor machine, applied to a semiconductor machine in a semiconductor manufacturing process, the method comprising:

providing a machine measurement parameter of the semiconductor manufacturing process, and a machine operation parameter of the semiconductor manufacturing process;

determining a difference between the machine measurement parameter of the pre-semiconductor manufacturing process and the machine operation parameter, and determining another difference between the machine measurement parameter of the semiconductor manufacturing process and the machine operation parameter of the semiconductor manufacturing process;

executing a statistical operation, wherein the difference between the machine measurement parameter of the semiconductor manufacturing process and the machine operation parameter is defined as a first parameter input value, and the difference between the machine operation parameter of the semiconductor manufacturing process and the machine measurement parameter is defined as a second parameter input value;

executing a fuzzy deciding operation, wherein a parameter output value is defined, a machine control parameter of the semiconductor manufacturing process is calculated, and the machine control parameter is set to the parameter output value; and

determining whether the machine control parameter of the semiconductor manufacturing process surpasses an acceptable range, wherein, when the machine control parameter of the semiconductor manufacturing process surpasses the acceptable range, repeating the step of executing the fuzzy deciding operation;

otherwise utilizing the machine control parameter of the semiconductor manufacturing process for adjusting the machine.

17. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 16, wherein the machine measurement parameter and the machine operation parameter are a wafer cleaning parameter, an exposure parameter, a coating parameter, or an etching parameter.

18. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 16, wherein the statistical operation comprises:

performing a fault detection and classification to classify the machine measurement parameter of the semiconductor manufacturing process to generate a related machine measurement parameter of the semiconductor manufacturing process, and to classify the machine operation parameter of the semiconductor manufacturing process to generate a related machine operation parameter of the semiconductor manufacturing process; and

performing a statistical weight for weighting the related machine measurement parameter of the semiconductor manufacturing process and for weighting the related machine operation parameter of the semiconductor manufacturing process to generate the first and the second parameter input values.

19. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 16, wherein the fuzzy deciding operation comprises:

performing a fuzzy operation to define a first membership function value corresponding to the first and the second parameter input values and a second membership function value corresponding to the parameter output value;

building a fuzzy rule, wherein a condition set of the fuzzy rule is the first membership function value;

performing a deciding operation, a result of the deciding operation is the second membership function value; and

performing a de-fuzzy operation for the second membership function value.

20. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 19, wherein the membership function value is a triangle-type membership function value.

21. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 19, wherein the fuzzy rule is an IF-THEN type.

22. The fuzzy control method for adjusting the semiconductor machine as claimed in claim 19, wherein the fuzzy operation is an area method, a gravity center method, or a height method.