System and method for controlling semiconductor wafer processing

A system for run-to-run control of a semiconductor processing unit, comprising:

• a generator operable to generate process parameters and an expected quality characteristic using a model and a desired quality characteristic provided by a user;
• circuitry responsive to said generator and operable to adjust selected inputs of the processing unit to process a semiconductor wafer using said generated process parameters:
• a real-time, in -situ sensor comprising optical device operable on a single wavelength to generate a signal proportional to the concentration of a predetermined chemical species present during processing of the wafer for measuring a quality characteristic of said process, wherein said sensor comprises:
• a monochromator operable to generate said signal proportional to the concentration of a predetermined chemical species present during processing of the wafer;
• a storage responsive to said monochromator and operable to store a value of said signal at predetermined intervals during the processing to generate data representative of an optical emission trace;
• and
• circuitry responsive to said storage and operable to use a function to convert a slope at an end-point of said optical emission trace to a quality characteristic for the process;
• a comparator responsive to said sensor and said generator and operatable to compare said measured quality characteristic with said expected quality characteristic;
• and
• circuitry responsive to said comparator and operable to adjust said model if said measured quality characteristic varies from said expected quality characteristic by more than a predetermined statistical amount.

A system for run-to-run control of a semiconductor processing unit, comprising:

• a generator operable to generate process parameters using a plurality of models each of which provides a transfer function from said process parameters to at least one of a plurality of quality characteristics at least one of said characteristics being unmeasurable after said process is complete;
• circuitry responsive to said generator and operable to adjust selected inputs of the processing unit to process a semiconductor wafer using said generated process parameters;
• an in-situ sensor for measuring a quality characteristic of said process in real-time during said process;
• a comparator responsive to said sensor and said generator and operable to compare the measured quality characteristics with the expected quality characteristics;
• and
• circuitry responsive to said comparator and operable to adjust the model if the measured quality characteristics vary from the expected quality characteristics by more than a predetermined statistical amount.

A system for run-to-run control of a semiconductor processing unit, comprising:

• a generator operable to generate process parameters and a plurality of expected quality characteristics using a plurality of models and desired quality characteristics;
• circuitry responsive to said generator and operable to adjust selected inputs of the processing unit to process the semiconductor wafer using said generated process parameters;
• a real-time, in-situ sensor for measuring a quality characteristic of said process wherein said sensor comprises:
• a monochromator operable to generate a signal proportional to the concentration of a predetermined chemical species present during processing of the wafer;
• a storage responsive to said monochromator and operable to store a value of a signal at predetermined intervals during the processing to generate data representative of an optical emission trace;
• and
• circuitry responsive to said storage and operable to use a function to convert a slope at an end-point of said optical emission trace to a quality characteristic for the process;
• a comparator responsive to said sensor and said generator and operable to compare the measured quality characteristics with the expected quality characteristics;
• circuitry responsive to said comparator and operable to adjust the model if the measured quality characteristics varies from the expected quality characteristics by more than a predetermined statistical amount.

A system for run-to-run control of a semiconductor processing unit, comprising:

• a generator operable to generate process parameters and an expected quality characteristic using a model and a desired quality characteristic provided by a user;
• circuitry responsive to said generating circuitry and operable to adjust selected inputs of the processing unit to process a semiconductor wafer using said generated process parameters;
• a real-time, in-situ sensor for measuring a signal correlated to a quality characteristic of said process which is not measurable after the process is complete;
• a comparator responsive to said sensor and said generator and operable to compare said measured quality characteristic with said expected quality characteristic;
• circuitry responsive to said comparator and operable to adjust said model if said measured quality characteristic varies from said expected quality characteristic by more than a predetermined statistical amount.

A system for run-to-run control of a semiconductor processing unit, comprising:

• a generator operable to generate process parameters and an expected quality characteristic using a model and a desired quality characteristic provided by a user;
• circuitry responsive to said generator and operable to adjust selected inputs of the processing unit to process a semiconductor wafer using said generated process parameters;
• a real-time, in-situ sensor for measuring a signal correlated to a non-directly observable quality characteristic of said process wherein said sensor comprises:
• a monochromator operable to generate a signal proportional to the concentration of a predetermined chemical species present during processing of the wafer;
• a storage responsive to said monochromator and operable to store a value of a signal at predetermined intervals during the processing to generate data representative of an optical emission trace;
• and
• circuitry responsive to said storage and operable to use a function to convert a slope at an end-point of said optical emission trace to a quality characteristic for the process;
• a comparator responsive to said sensor and said generator and operable to compare said measured quality characteristic with said expected quality characteristic;
• circuitry responsive to said comparator and operable to adjust said model if said measured quality characteristic varies from said expected quality characteristic by more than a predetermined statistical amount.