Measurement Of Multiple Patterning Parameters

A method comprising:

• illuminating a measurement site on a surface of a semiconductor wafer, wherein the measurement site includes a metrology target having a nominal grating pitch generated by a multiple patterning process;
• detecting an amount of light diffracted from the illuminated measurement site at a diffraction order different from a zero diffraction order;
• determining at least one structural parameter value indicative of a geometric error induced by the multiple patterning process based on the amount of detected light;
• and
• storing the at least one structural parameter value in a memory.

A system comprising:

• a metrology tool including an illumination source and a detector configured to perform measurements of a target structure;
• and
• a computing system configured to:
• receive a first amount of measurement data associated with measurements of a first plurality of measurement sites on a surface of a semiconductor wafer, wherein each of the first plurality of measurement sites includes a single patterned metrology target having a first grating pitch generated by a first patterning step of a multiple patterning process and a multiple patterned metrology target having a second grating pitch generated by the first patterning step and a subsequent patterning step of the multiple patterning process, wherein the single patterned metrology target and the multiple patterned metrology target are disposed adjacent to one another at each measurement site;
• determine at least one structural parameter value associated with each of the first plurality of measurement sites based on the first amount of measurement data and a combined measurement model, wherein a model parameter characterizing the single patterned metrology target and a model parameter characterizing the multiple patterned metrology target are linked in the combined measurement model, and wherein the at least one structural parameter value is indicative of a geometric error induced by the multiple patterning process;
• and
• store the at least one structural parameter value in a memory.

A system comprising:

• an illumination source configured to illuminate a measurement site on a surface of a semiconductor wafer, wherein the measurement site includes a metrology target having a nominal grating pitch generated by a multiple patterning process;
• a detector configured to detect an amount of light diffracted from the illuminated measurement site at a diffraction order different from a zero diffraction order;
• and
• a computing system configure to:
• determine at least one structural parameter value indicative of a geometric error induced by the multiple patterning process based on the amount of detected light;
• and
• store the at least one structural parameter value in a memory.