Process control system, process control method, and method of manufacturing electronic apparatus

• US 7,596,421 B2
• Filed: 06/21/2006
• Issued: 09/29/2009
• Est. Priority Date: 06/21/2005
• Status: Active Grant

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Akiyama, Kazutaka, Sugamoto, Junji, Ushiku, Yukihiro, Harakawa, Shoichi
• Primary Examiner(s): DeCady; Albert
• Assistant Examiner(s): Garland; Steven R
• Application Number:
  US11/471,675
• Publication Number:
  US 20060287754A1
• Time in Patent Office: 1,196 Days
• Field of Search: 700/108, 700/109, 700/121, 438/14, 702/188
• US Class Current: 700/121
• CPC Class Codes: G05B 19/41875 characterised by quality surveillance of production
• CPC Class Codes: G05B 2219/31477 Display correlated data so as to represent the degree of correlation
• CPC Class Codes: G05B 2219/32057 Control cell as function of correlation between stored and detected machine state
• CPC Class Codes: G05B 2219/32097 Recipe programming for flexible batch
• CPC Class Codes: G05B 2219/45031 Manufacturing semiconductor wafers
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A process control system includes a client computer which prepares a correlation between a reference monitored value of apparatus information and a feature quantity, a manufacturing execution system which prepares a processing recipe describing, as a first setting value in an actual manufacturing process, a value of the control parameter, an apparatus information collection section which collects an objective monitored value of the apparatus information in operation of the actual manufacturing process with the first setting value, a feature quantity calculation section which calculates a value of a feature quantity corresponding to the objective monitored value based on the correlation, a parameter calculation section which calculates a second setting value in the actual manufacturing process on the basis of the value of the feature quantity, and an apparatus control unit which changes the processing recipe with the second setting value being as a setting value of the second step.

Claims

1. A process control system comprising:

a monitor unit which monitors apparatus information indicating a processing state of a manufacturing apparatus;

an apparatus information collection unit which collects a monitored value of the apparatus information from the monitor unit in operation of a manufacturing process;

a correlation preparation unit which prepares a correlation between a test monitored value of the apparatus information in a test manufacturing process with respect to a test wafer, and a feature quantity obtained from a processing parameter for controlling the manufacturing apparatus and a finished form in the test manufacturing process;

a process management unit which calculates a setting value of the processing parameter in an objective manufacturing process on the basis of at least one of a plurality of estimated values of the feature quantity in combination with a dimension of a processing objective structure in the objective manufacturing process with respect to an objective wafer, said plurality of estimated values being calculated, on the basis of the correlation prepared by the correlation preparation unit, with respect to a plurality of reference monitored values of the apparatus information except for abnormal values in a distribution of said plurality of reference monitored values in a reference manufacturing process with respect to a plurality of reference wafers; and

an apparatus control unit which controls the manufacturing apparatus in accordance with a processing recipe in which the setting value is described in a processing step in the objective manufacturing process,

wherein the process management unit determines abnormal values in a distribution of said plurality of reference monitored values;

classifies abnormal values which are reproduced by an appearance distribution region among the abnormal values determined in the distribution of the reference monitored values into an abnormal mode; and

prepares a new correlation between the abnormal value of a first abnormal wafer classified into the abnormal mode, and a feature quantity calculated on the basis of a finished form of the first abnormal wafer.

2. The process control system according to claim 1, wherein the processing parameter includes a time, a temperature, a flow rate, and a pressure.

3. The process control system according to claim 1, wherein the finished form includes finished dimensions of a width and a depth of a pattern, a finished dimension of a thickness of the pattern, an angle of a sidewall of the pattern, and a line edge roughness of the pattern.

4. The process control system according to claim 1, wherein the process management unit calculates, when a new monitored value of the apparatus information collected while processing the objective wafer in accordance with the processing recipe is classified into the abnormal mode, a new estimated value of the feature quantity corresponding to the new monitored value on the basis of the new correlation;

calculates a new setting value of the processing parameter on the basis of a dimension of the processing objective structure and the new estimated value; and

changes the setting value of a processing step in the processing recipe on the basis of the new setting value.

5. A process control method comprising:

preparing, by executing a test manufacturing process with respect to a test wafer, a correlation between a test monitored value of apparatus information indicating a processing state of a manufacturing apparatus and a feature quantity obtained from a processing parameter for controlling the manufacturing apparatus and a finished form in the test manufacturing process;

acquiring, by executing a reference manufacturing process with respect to a plurality of reference wafers, a plurality of reference monitored values of the apparatus information with respect to said plurality of reference wafers;

determining abnormal values in a distribution of said plurality of reference monitored values;

calculating on the basis of the correlation a plurality of estimated values of the feature quantity respectively corresponding to said plurality of reference monitored values except for the abnormal values;

calculating a setting value of the processing parameter in objective manufacturing process on the basis of a dimension of a processing objective structure in the objective manufacturing process with respect to an objective wafer, and at least one of said plurality of estimated values;

preparing a processing recipe in which the setting value is described in a processing step in the objective manufacturing process;

classifying abnormal values which are reproduced by an appearance distribution region among the abnormal values determined in the distribution of the reference monitored values into an abnormal mode; and

preparing a new correlation between the abnormal value of a first abnormal wafer classified into the abnormal mode, and a feature quantity calculated on the basis of a finished form of the first abnormal wafer.

6. The process control method according to claim 5, wherein the processing parameter includes a time, a temperature, a flow rate, and a pressure.

7. The process control method according to claim 5, wherein the finished form includes finished dimensions of a width and a depth of a pattern, a finished dimension of a thickness of the pattern, an angle of a sidewall of the pattern, and a line edge roughness of the pattern.

8. The process control method according to claim 5, further comprising:

calculating, when a new monitored value of the apparatus information collected while processing the objective wafer in accordance with the processing recipe is classified into the abnormal mode, a new estimated value of the feature quantity corresponding to the new monitored value on the basis of the new correlation;

calculating a new setting value of the processing parameter on the basis of a dimension of the processing objective structure and the new estimated value; and

changing the setting value of a processing step in the processing recipe on the basis of the new setting value.

9. A method of manufacturing an electronic apparatus, comprising:

preparing, by executing a test manufacturing process with respect to a test wafer, a correlation between a test monitored value of apparatus information indicating a processing state of a manufacturing apparatus, and a feature quantity obtained from a processing parameter for controlling the manufacturing apparatus and a finished form in the test manufacturing process;

collecting, by executing a reference manufacturing process with respect to a plurality of reference wafers, a plurality of reference monitored values of the apparatus information with respect to said plurality of reference wafers;

determining abnormal values in a distribution of said plurality of reference monitored values;

calculating on the basis of the correlation a plurality of estimated values of the feature quantity respectively corresponding to said plurality of reference monitored values except for the abnormal values;

calculating a setting value of the processing parameter in an objective manufacturing process on the basis of a dimension of a processing objective structure in the objective manufacturing process with respect to an objective wafer, and at least one of said plurality of estimated values;

preparing a processing recipe in which the setting value described is in a processing step in the objective manufacturing process;

processing the objective wafer by the manufacturing apparatus in accordance with the processing recipe;

classifying abnormal values which are reproduced by an appearance distribution region among the abnormal values determined in the distribution of the reference monitored values into an abnormal mode; and

preparing a new correlation between the abnormal value of a first abnormal wafer classified into the abnormal mode, and a feature quantity calculated on the basis of a finished form of the first abnormal wafer.

10. The method of manufacturing an electronic apparatus according to claim 9, wherein the processing parameter includes a time, a temperature, a flow rate, and a pressure.

11. The method of manufacturing an electronic apparatus according to claim 9, further comprising:

calculating, when a new monitored value of the apparatus information collected while processing the objective wafer in accordance with the processing recipe is classified into the abnormal mode, a new estimated value of the feature quantity corresponding to the new monitored value on the basis of the new correlation;

calculating a new setting value of the processing parameter on the basis of a dimension of the processing objective structure and the new estimated value; and

changing the setting value of a processing step in the processing recipe on the basis of the new setting value.