System and method for monitoring sensor linearity as part of a production process

A computer-implemented method for automated monitoring of a measurement performance of at least one sensor having a predictable measurement performance over a range of operating set points of a tool of a semiconductor manufacturing process, wherein the at least one sensor provides data sensitive to at least one of a tool state or a process state change, the method comprising:

• while operating the tool during the semiconductor manufacturing process:
• collecting, at each of a plurality of points in time, actual measurement data from the at least one sensor at more than one operating set point of the tool of the semiconductor manufacturing process associated with a tool state or a process state;
• storing the collected measurement data along with an indication of a respective set point at which the actual measurement was taken and a respective time during which the actual measurement was taken to create time-indexed pairs of operating set points and respective measurement data;
• predicting expected measurement data for at least one of the at least one sensor for at least one operating set point of the tool of the semiconductor manufacturing process based on the collected, actual measurement data from the at least one sensor at the more than one operating set point of the tool of the semiconductor manufacturing process according to the predictable measurement performance of the at least one sensor, wherein the predicting comprises:
• selecting a first time-indexed pair of operating set points and respective actual measurement data corresponding to a lower limit of an operating range encountered by the tool and the at least one sensor across at least one of a plurality of recipes implemented during the semiconductor manufacturing process;
• selecting a second time-indexed pair of operating set points and respective actual measurement data corresponding to an upper limit of an operating range encountered by the tool and the at least one sensor across the at least one of the plurality of recipes implemented during the semiconductor manufacturing process;
• selecting a third time-indexed pair of operating set points and respective actual measurement data corresponding to an intermediate point of an operating range encountered by the tool and the at least one sensor across the at least one of the plurality of recipes implemented during the semiconductor manufacturing process;
• and
• modeling the at least one sensor using the first, second and third time-indexed pairs;
• collecting additional actual measurement data from the at least one sensor from at least one of the more than one operating set point of the tool of the semiconductor manufacturing process for which expected measurement data was predicted;
• evaluating a measurement performance of the at least one sensor by comparing the additional actual measurement data from the at least one sensor at a set point of the tool of the semiconductor manufacturing process with expected measurement data predicted for the at least one sensor at the set point of the tool of the semiconductor manufacturing process;
• and
• in response to the additional actual measurement data from the at least one sensor at a set point of the tool of the semiconductor manufacturing process not being within a predicted range of the expected measurement data for the at least one sensor at the set point of the tool of the semiconductor manufacturing process, automatically initiating maintenance on at least one of the at least one sensor or the tool of the semiconductor manufacturing process.

A system for implementing an automatic and non-disruptive sensor health monitoring scheme for at least one sensor having a predictable measurement performance over a range of operating set points during execution of a recipe on a substrate within a processing chamber of a plasma processing system as part of a device fabrication process, comprising:

• at least one sensor configured to collect sensor data to facilitate monitoring operating set points during execution of the recipe;
• an interface configured to receive sensor data collected from the at least one sensor;
• and
• an analytical computer system communicably coupled with said interface and having a memory and a processor configured to execute instructions stored in memory, the processor being operative to execute instructions:
• to store collected sensor data from the at least one sensor in response to operating set point changes;
• to associate each actual measurement returned by the at least one sensor with an indication of a respective operating set point at which the actual measurement was taken and a respective time during which the actual measurement was taken to create time-indexed pairs of operating set points and respective measurement data;
• to predict expected measurement data for at least one of the at least one sensor for at least one operating set point based on collected, actual measurement data from the at least one sensor at the more than one operating set point according to the predictable measurement performance of the at least one sensor;
• to evaluate a health of the at least one sensor based by comparing additional actual measurement data from the at least one sensor at a set point, with expected measurement data predicted for the at least one sensor at the set point;
• and
• in response to the additional actual measurement data from the at least one sensor at the set point not being within a predicted range of the expected measurement data for the at least one sensor at the set point, transmitting a communication to cause maintenance to be performed on the at least one sensor.