Plasma processing method and apparatus

• US 7,289,866 B2
• Filed: 01/07/2005
• Issued: 10/30/2007
• Est. Priority Date: 01/08/2004
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Tomoyasu, Masayuki
• Primary Examiner(s): Masinick; Michael D.
• Application Number:
  US11/030,049
• Publication Number:
  US 20050154482A1
• Time in Patent Office: 1,026 Days
• Field of Search: 700/121, 700/123, 216/67
• US Class Current: 700/121
• CPC Class Codes: G05B 2219/32201 Build statistical model of past normal proces, compare with actual process
• CPC Class Codes: G05B 2219/45031 Manufacturing semiconductor wafers
• CPC Class Codes: H01J 37/32091 the radio frequency energy being capacitively coupled to the plasma
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

In a plasma processing method for monitoring data, first and second measurement data are obtained; and a first and a second model are formulated based on the first and the second measurement data. Further, third measurement data is obtained; and weight factors are obtained by setting the third measurement data as weighted measurement data wherein the weighted measurement data is obtained by multiplying each of the first and the second measurement data by one of the weight factors to produce first and second weighted data and summing the thus produced first and the second weighted data. Therefore, a third model is formulated by multiplying each of the first and the second model by one of the weight factors to produce first and second weighted models, and summing the thus produced first and the second weighted models.

Claims

1. A plasma processing apparatus for monitoring information on a plasma processing based on a model or for updating an operating condition of the plasma processing based on a change in the information on the plasma processing caused by the model, when performing the plasma processing on an object by setting the operating condition and generating a plasma in an airtight processing vessel, wherein the model is made by performing a multivariate analysis based on measurement data measured by one or more measuring devices, the apparatus comprising:

a means for obtaining first measurement data by using the measuring devices while performing the plasma processing by setting a first operating condition;

a means for formulating a first model based on the first measurement data by the multivariate analysis;

a means for obtaining second measurement data by using the measuring devices while performing the plasma processing by setting a second operating condition;

a means for formulating a second model based on the second measurement data by the multivariate analysis;

a means for obtaining third measurement data by using the measuring devices while performing the plasma processing by setting a third operating condition;

a means for obtaining weight factors by setting the third measurement data as weighted measurement data wherein the weighted measurement data is obtained by multiplying each of the first and the second measurement data by one of the weight factors to produce first and second weighted data and summing the thus produced first and the second weighted data; and

a means for formulating a third model for the third operating condition by multiplying each of the first and the second model by said one of the weight factors to produce first and second weighted models, and summing the thus produced first and the second weighted models.

2. A plasma processing apparatus for monitoring information on a plasma processing based on a model or for updating an operating condition of the plasma processing based on a change in the information on the plasma processing caused by the model, when performing the plasma processing on an object by setting the operating condition and generating a plasma in an airtight processing vessel, wherein the model is made by performing a multivariate analysis based on measurement data measured by one or more measuring devices, the apparatus comprising:

a means for obtaining measurement data for each of a plurality of different operating conditions by using the measuring devices while performing the plasma processing by setting the operating conditions;

a means for formulating a model for each of the operating conditions based on the measurement data by performing the multivariate analysis;

a means for obtaining new measurement data from the measuring devices while performing the plasma processing by setting a new operating condition;

a means for obtaining weight factors by setting the new measurement data as weighted measurement data for the new operating condition wherein the weighted measurement data is obtained by multiplying the measurement data for each of the operating conditions by one of the weight factors to produce weighted measurement data for the operating conditions, and summing the thus produced weighted measurement data; and

a means for formulating a new model for the new operating condition by multiplying each of the models by said one of the weight factors to produce weighted models, and summing the thus produced weighted models.

3. The plasma processing apparatus of claim 2, wherein each operating condition includes plural parameters;

the operating conditions include a reference operating condition and one or more additional operating conditions, a value of only one parameter of each additional operating condition being different from that of the reference operating condition; and

values of one or more parameters of the new operating condition are different from those of the reference operating condition, said one or more parameters being identical to one or more parameters changed in the operating conditions.

4. The plasma processing apparatus of claim 3, wherein said one or more parameters changed in the operating conditions are one or more parameters selected from the group consisting of a high frequency power supplied to an electrode, installed in the processing vessel, for generating a plasma;

an inner pressure of the processing vessel;

a flow rate ratio between multiple species of processing gases supplied into the processing vessel for performing the plasma processing; and

a pressure of a backside gas supplied to a rear surface of the object for cooling the object.

5. The plasma processing apparatus of claim 2, wherein the model is a correlation factor between the measurement data and processing result data by the plasma processing;

and the processing results are predicted based on a correlation equation made by the correlation factor.

6. The plasma processing apparatus of claim 2, wherein the model is a correlation factor between the measurement data and processing result data by the plasma processing;

and it is determined or predicted whether the plasma processing is abnormal or not based on a correlation equation made by the correlation factor.

7. The plasma processing apparatus of claim 2, wherein the model is a correlation factor between the measurement data and processing result data by the plasma processing;

and it is estimated why an abnormality in the plasma processing is generated based on a correlation equation made by the correlation factor.

8. The plasma processing apparatus of claim 2, wherein the model is a correlation factor between the measurement data and processing result data by the plasma processing and a correlation equation made by the correlation factor is used as reference data for compensating a change of the plasma processing.

9. The plasma processing apparatus of claim 2, wherein the multivariate analysis is performed by a partial least square method.

10. The plasma processing apparatus of claim 2, wherein the multivariate analysis is performed by a principal component analysis method.