System for extraction of key process parameters from fault detection classification to enable wafer prediction

• US 7,974,728 B2
• Filed: 02/05/2008
• Issued: 07/05/2011
• Est. Priority Date: 05/04/2007
• Status: Expired due to Fees

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Ko, Francis, Zuo, Kewei, Lin, Chun-Hsien, Lo, Henry, Wang, Jean
• Primary Examiner(s): Shechtman; Sean P
• Application Number:
  US12/026,361
• Publication Number:
  US 20080275585A1
• Time in Patent Office: 1,246 Days
• Field of Search: 700108-111, 700/32, 700/709, 700/51, 700/15, 700/49, 700/83, 700/95, 700/121, 700/174, 700/175, 700/177, 702179-185, 706/13
• US Class Current: 700/121
• CPC Class Codes: G05B 23/0221 Preprocessing measurements, e.g. data collection rate adjustment; Standardization of measurements; Time series or signal analysis, e.g. frequency analysis or wavelets; Trustworthiness of measurements; Indexes therefor; Measurements using easily measured parameters to estimate parameters difficult to measure; Virtual sensor creation; De-noising; Sensor fusion; Unconventional preprocessing inherently present in specific fault detection methods like PCA-based methods

Abstract

A system, method, and computer readable medium for extracting a key process parameter correlative to a selected device parameter are provided. In an embodiment, the key process parameter is determined using a gene map analysis. The gene map analysis includes grouping highly correlative process parameter and determining the correlation of a group to the selected device parameter. In an embodiment, the groups having greatest correlation to the selected device parameter are displayed in a correlation matrix and/or a gene map.

Claims

1. An apparatus comprising a non-transitory computer-readable medium encoded with a computer program that, when executed performs the steps of:

selecting a device parameter associated with an integrated circuit, wherein the selected device parameter includes one of a change in saturation current, a leakage parameter, and a speed parameter;

collecting process data, wherein the process data includes time series process data and values associated with a plurality of process parameters;

summarizing the time series process data; and

performing a correlation analysis, wherein the correlation analysis identifies a key parameter included in the plurality of process parameters, wherein the key process parameter is correlative to the selected device parameter, and wherein the correlation analysis includes generating a gene map for the selected device parameter, wherein the gene map includes a first axis showing a plurality of process steps and a second axis illustrating the plurality of process parameters and illustrates the plurality of process parameters relative correlation to the selected device parameter at the plurality of process steps.

2. The apparatus of claim 1, further comprising:

collecting wafer test data, wherein the wafer test data includes values associated with a plurality of wafer test parameters; and

wherein the correlation analysis includes identifying a key wafer test parameter of the plurality of wafer test parameters that is correlative to the selected device parameter.

3. The apparatus of claim 1, wherein the summarizing the time series process data includes determining a statistical value from a group of statistical values consisting of a maximum value, a minimum value, a standard deviation value, an average value, and combinations thereof.

4. The apparatus of claim 1, wherein the correlation analysis includes grouping the plurality of process parameters to provide at least a first group and a second group.

5. The apparatus of claim 4, wherein a coefficient of determination of the first group with respect to the selected device parameter is greater than a coefficient of determination of any one process parameter included in the first group.

6. The apparatus of claim 4, wherein the grouping the plurality of process parameters includes determining a correlation among the plurality of process parameters.

7. The apparatus of claim 6, wherein the grouping the plurality of process parameters includes selecting process parameters such that the first group has a correlation among the plurality of process parameters of coefficient of determination (an R² value) of at least 0.8.

8. The apparatus of claim 4, further comprising:

determining a correlation of the first group to the selected device parameter using principal component transformation and stepwise regression.

9. The apparatus of claim 4, further comprising:

providing a correlation matrix for the first group.

10. The apparatus of claim 1, wherein the plurality of process parameters are grouped into a third group and a fourth group, and wherein the gene map includes a ranking of the third group and the fourth group, wherein the ranking provides for a relative correlation to the selected device parameter.

11. The apparatus of claim 1, further comprising:

performing a split lot to determine a value for the key process parameter.

12. A non-transitory computer readable medium comprising computer readable instructions to perform a correlation analysis, the computer readable instructions providing instructions to:

receive process data and corresponding device performance data, wherein the process data is associated with a first, second, third, and fourth process parameter, wherein the first, second, third, and fourth process parameter are each associated with an integrated circuit and indicative of performance of the integrated circuit, and wherein the performance of the integrated circuit is determined by at least one device parameter selected from the group consisting of a saturation current, a leakage parameter, and a speed parameter;

summarize the process data;

group the first and second process parameters into a first group and the third and fourth process parameters into a second group, wherein the grouping is determined using the correlation between the first and second parameter and the correlation between the third and fourth process parameter;

generate a correlation matrix for the first group;

generate a gene map for the at least one device parameter having a first axis showing a plurality of process steps and a second axis illustrating a plurality of process parameters including the first, second, third, and fourth process parameters, wherein the gene map includes the relative correlation of the first group to the at least one device parameter and the relative correlation of the second group to the at least one device parameter at the plurality of process steps.

13. The computer readable medium of claim 12, further comprising instructions to:

generate a hierarchical binary tree including the first, second, third, and fourth process parameters.

14. The computer readable medium of claim 12, wherein the summarizing the data includes summarizing time series equipment data.