Method for Improving Efficiency of a Manufacturing Process Such as a Semiconductor Fab Process

• US 20070260350A1
• Filed: 08/22/2005
• Published: 11/08/2007
• Est. Priority Date: 08/20/2004
• Status: Abandoned Application

• Current Assignee: PDF Solutions
• Original Assignee: PDF Solutions
• Inventors: Zagrebnov, Maxim
• Application Number:
  US11/660,344
• Publication Number:
  US 20070260350A1
• Time in Patent Office: Days
• US Class Current: 700/121
• CPC Class Codes: G05B 19/41875 characterised by quality surveillance of production
• CPC Class Codes: G05B 2219/32187 Correlation between controlling parameters for influence on quality parameters
• CPC Class Codes: G05B 2219/32194 Quality prediction
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

The present invention provides a method for improving the efficiency of a product manufacturing process such as a semiconductor fab process, wherein a given step of the process has a quality result which can be actually measured on each product or group of products, and wherein the process comprises a subsequent, adjustable step, the method comprising:—providing a correlation model of the behavior of said given step as a function of available parameters;—for each product or group of products at the output of said manufacturing step, computing a predicted quality result based on said correlation model as a function of the actual values of the parameters during the manufacturing step, and—providing the quality result to a control system for adjusting said subsequent step.

Claims

1. A method for improving efficiency of a product manufacturing process such as a semiconductor fab process, wherein a given step of the process has a quality result which can be predicted for each product or group of products, comprising:

providing a correlation model of the performance of a given step as a function of available process parameters;

for each product or group of products at the output of said manufacturing step, computing a predicted quality result based on said correlation model as a function of the actual values of the parameters during the manufacturing step, and

only if the predicted quality result is lower than a predetermined threshold, selecting the product or group of products for in-line measurement.

2. A method according to claim 1, wherein the provided correlation model is a function of a complete set of available parameters, while the predicted quality result is a function of the incomplete set of actual values of the parameters during the manufacturing step.

3. A method according to claim 1, wherein said given step has no in-line measurements associated, and the said selecting step is only based on quality result of the prediction, and also on the predicted value for this product.

4. A method according to claim 1, wherein said predicted quality result includes a value and a degree of confidence of said value.

5. A method according to claim 4, further including a correlation model calibration step that is at least based on real quality result measurement for a limited of product samples.

6. A method according to any one of claims 1 to 5, wherein said process step is a plasma deposition step.

7. A method according to claim 6, wherein the said model calibration is at least based on final Electric Test or Yield results at the end of a processing sequence.

8. A method according to claim 1, wherein said manufacturing process further comprises a subsequent, adjustable step, the method further comprising providing the quality result to a control system for adjusting said subsequent step.

9. A method according to claims 6 and 8 taken in combination, wherein said subsequent step is a chemical mechanical polishing (CMP) step.

10. A method according to claim 9, wherein the adjustment of said CMP comprises adjustment of the duration of an over-polish phase of said subsequent step.

11. A method according to claims 6 and 8 taken in combination, wherein said subsequent step is an etching step.

12. A method for improving the efficiency of a product manufacturing process such as a semiconductor fab process, wherein a given step of the process has a quality result which can be actually measured on each product or group of products, and wherein the process comprises a subsequent, adjustable step, the method comprising:

providing a correlation model of the behavior of said given step as a function of available parameters;

for each product or group of products at the output of said manufacturing step, computing a predicted quality result based on said correlation model as a function of the actual values of the parameters during the manufacturing step, and

providing the quality result to a control system for adjusting said subsequent step.

13. A method according to claim 12, wherein said given step is a plasma deposition step and said subsequent step is a chemical mechanical polishing step.