Scatterometry techniques to ascertain asymmetry profile of features and generate a feedback or feedforward process control data associated therewith

A method of determining asymmetry associated with a feature and generating process control data associated therewith, comprising the steps of:

• directing radiation at the feature;
• detecting reflected radiation from the feature;
• ascertaining an asymmetry of the feature using the detected reflected radiation;
• and
• generating process control data based on the asymmetry of the feature, wherein directing radiation comprises directing linearly polarized light at a non-perpendicular angle to a substrate having the feature thereon, wherein the linearly polarized light has a range of wavelengths of about 100 nm to about 1000 nm.

A method of maintaining a relatively spatially uniform dopant concentration is source/drain regions independent of an asymmetry gate electrode profile, comprising the steps of:

• directing radiation at a first side of a patterned gate electrode;
• detecting reflected radiation from the first side of the patterned gate electrode;
• directing radiation at a second, opposing side of the patterned gate electrode;
• detecting reflected radiation from the first side of the patterned gate electrode;
• determining a profile characteristic associated with the first and second sides of the patterned gate electrode using the detected reflected radiation associated with the first and second sides, respectively;
• determining an asymmetry of the patterned gate electrode using the determined profile characteristics of the first and second sides thereof;
• and
• generating ion implantation process control data associated with the asymmetry of the patterned gate electrode.

A method of determining a feature profile using a database comprising:

• directing an incident beam of polarized light at a first side of a feature, wherein the polarized light comprises a range of wavelengths;
• detecting a phase of a first reflected beam, wherein the phase is a function of the range of wavelengths;
• detecting an intensity of a first reflected beam, wherein the intensity is a function of the range of wavelengths;
• directing an incident beam of polarized light at a second side of the feature, wherein the polarized light comprises a range of wavelengths;
• detecting a phase of a second reflected beam, wherein the phase is a function of the range of wavelengths;
• detecting an intensity of a second reflected beam, wherein the intensity is a function of the range of wavelengths;
• and
• correlating a first set of phase and intensity and a second set of phase and intensity as a function of the range of wavelengths with a database containing a plurality of intensity and phase data of known feature profiles to determine a profile of the feature.
• 25.The method of claim 24, wherein directing an incident beam of polarized light at a second side of the feature comprises rotating a stage about 180 degrees from an original position such that the incident beam is directed at the second side of the feature.

A method of in-situ detection and control of asymmetry of a feature profile comprising:

• directing an incident beam of radiation at a first side of a feature;
• detecting a first reflected beam associated with the first side of the feature;
• directing an incident beam of radiation at a second side of the feature;
• detecting the second reflected beam associated with the second side of the feature;
• determining a pattern profile using the collected data from the first side and the second side of the feature;
• and
• changing one or more process parameters based on the determined pattern profile to reduce asymmetry as between the first side and the second side of the feature.