Combined optical profilometry and projection microscopy of integrated circuit structures

A method for calibrating imaging data from a projection microscope using shape profiles determined from optical profilometry, comprising the steps of:

• acquiring a first microscopy image of at least a first portion of first structures;
• acquiring a second microscopy image of at least a second portion of second structures;
• determining a first critical dimension estimate of the first structures from the first microscopy image;
• determining a second critical dimension estimate of the second structures from the second microscopy image;
• acquiring first optical profilometry data of at least a third portion of the first structures to generate a first profile shape;
• acquiring second optical profilometry data of at least a fourth portion of the second structures to generate a second profile shape;
• determining a third critical dimension estimate of the first structures from the first profile shape;
• determining a fourth critical dimension estimate of the second structures from the second profile shape;
• and
• determining differences between the first critical dimension estimate and the third critical dimension estimate and between the second critical dimension estimate and the fourth critical dimension estimate, the differences dependent on at least one physical property of the first structures and the second structures.

A method for calibrating imaging data from microscopy of first structures using a first physical shape determined from optical profilometry of the first structures, comprising the steps of:

• acquiring a first microscopy image of at least a first portion of the first structures;
• determining a first critical dimension estimate of the first structures from the first microscopy image;
• acquiring optical profilometry data of at least a second portion of the first structures to provide a profile shape;
• determining a second critical dimension estimate of the first structures from the profile shape;
• and
• determining a difference dependent on a first density of the first structures between the first critical dimension estimate and the second critical dimension estimate.

A method for using microscopy to augment the use of optical profilometry to determine a profile shape of integrated circuit structures, comprising the steps of:

• acquiring a microscopy image of at least a first portion of the integrated circuit structures;
• determining a critical dimension estimate of the integrated circuit structures from the microscopy image;
• and
• generating a library of calculated diffraction spectra corresponding to a set of profile shapes with critical dimensions based on the critical dimension estimate obtained from the microscopy image.

A method for using optical profilometry to interpret microscopy imaging data, the method comprising the steps of:

• acquiring a microscopy image of a first integrated circuit structure;
• performing optical profilometry on second integrated circuit structures to determine a first profile shape;
• classifying the first profile shape as a profile type selected from a set of profile types;
• and
• processing the microscopy image of the first integrated circuit structure based on the profile type.

A method for augmenting a function of critical dimension values versus a critical dimension dependent characteristic, critical dimension values of pre-augmented data of the function being based on microscopy of first integrated circuit structures, the function being augmented with augmentation data where critical dimension values are based on optical profilometry of second integrated circuit structures, the method comprising the steps of:

• performing optical profilometry on a first portion of first structures to determine a first profile shape of the first structures;
• determining a first critical dimension estimate corresponding to the first profile shape using optical profilometry;
• determining a first critical dimension dependent characteristic corresponding to the first critical dimension estimate to provide a first critical dimension/critical dimension dependent characteristic data point;
• and
• adding the first critical dimension/critical dimension dependent characteristic data point to the pre-augmented data.