Method and apparatus for determining column dimensions using scatterometry

A method for determining columns dimensions, comprising:

• providing a wafer having a test structure comprising a plurality of trenches each having a width dimension, and a plurality of columns defined in the trenches, each column having a width dimension less than the width dimension of the trench in which it is defined;
• illuminating at least a portion of the columns with a light source;
• measuring light reflected from the illuminated portion of the columns to generate a reflection profile;
• comparing the generated reflection profile to a library of reference reflection profiles each reference reflection profile having an associated column dimension metric;
• selecting a reference reflection profile closest to the generated reflection profile;
• and
• determining a dimension of the columns based on the column dimension metric associated with the selected reference reflection profile.

A method for determining column dimensions, comprising:

• providing a wafer having a test structure comprising a plurality of trenches each having a width dimension, and a plurality of columns defined in the trenches, each column having a width dimension less than the width dimension of the trench in which it is defined;
• illuminating at least a portion of the columns with a light source;
• measuring light reflected from the illuminated portion of the columns to generate a reflection profile;
• and
• comparing the generated reflection profile to a target reflection profile;
• and
• determining a dimension of the columns based the comparison of the generated reflection profile and the target reflection profile.

A metrology tool adapted to receive a wafer having a test structure comprising a plurality of trenches each having a width dimension, and a plurality of columns defined in the trenches, comprising:

• a light source adapted to illuminate at least a portion of the columns, each column having a width dimension less than the width dimension of the trench in which it is defined;
• a detector adapted to measure light reflected from the illuminated portion of the columns to generate a reflection profile;
• and
• a data processing unit adapted to determine a dimension of the columns based on the reflection profile.

A processing line, comprising:

• a processing tool adapted to process wafer in accordance with an operating recipe;
• a metrology tool adapted to receive a wafer having a test structure comprising a plurality of trenches each having a width dimension, and a plurality of columns defined in the trenches, each column having a width dimension less than the width dimension of the trench in which it is defined, the metrology tool comprising:
• a light source adapted to illuminate at least a portion of the columns;
• a detector adapted to measure light reflected from the illuminated portion of the columns to generate a reflection profile;
• and
• a data processing unit adapted determine a dimension of the columns based on the reflection profile;
• and
• a controller adapted to determine at least one parameter of the operating recipe of the processing tool based on the determined column dimension.

A metrology tool adapted to receive a wafer having a test structure comprising a plurality of trenches each having a width dimension, and a plurality of columns defined in the trenches, comprising:

• a light source adapted to illuminate at least a portion of the columns, each column having a width dimension less than the width dimension of the trench in which it is defined;
• a detector adapted to measure light reflected from the illuminated portion of the columns to generate a reflection profile;
• and
• a data processing unit adapted to compare the generated reflection profile to a library of reference reflection profiles, each reference reflection profile having an associated column dimension metric, select a reference reflection profile closest to the generated reflection profile, and determine a dimension of the columns based on the column dimension metric associated with the selected reference reflection profile.

A metrology tool adapted to receive a wafer having a test structure comprising a plurality of trenches each having a width dimension and a plurality of columns defined in the trenches, comprising:

• a light source adapted to illuminate at least a portion of the columns, each column having a width dimension less than the width dimension of the trench in which it is defined;
• a detector adapted to measure light reflected from the illuminated portion of the columns to generate a reflection profile;
• and
• a data processing unit adapted to compare the generated reflection profile to a target reflection profile and determine a dimension of the columns based on the comparison of the generated reflection profile and the target refection profile.

A metrology tool, comprising:

• means for receiving a wafer having a test structure comprising a plurality of trenches each having a width dimension, and a plurality of columns defined in the trenches, each column having a width dimension less than the width dimension of the trench in which it is defined;
• means for illuminating at least a portion of the columns with a light source;
• means for measuring light reflected from the illuminated portion of the columns to generate a reflection profile;
• and
• means for determining a dimension of the columns based on the reflection profile.