Enabling Scatterometry as an In-Line Measurement Technique for 32 nm BEOL Application

Dependence-Analysis-Based Data-Refinement in Optical Scatterometry for Fast Nanostructure Reconstruction

“…Compared with other techniques such as scanning electron microscopy (SEM), atomic force microscopy (AFM) [4], and near-field scanning optical microscope (NSOM) [5], optical scatterometry [6,7], also known as optical critical dimension metrology or optical critical dimension (OCD) metrology, is more suitable for monitoring, assessing, and optimizing the nano-manufacturing processes due to its advantages of being non-contact, non-destructive, low in cost, and easy to integrate, etc. Recently, optical scatterometry has been applied in many fields with great success, such as the process control for back-end-of-the-line (BEOL) [8], the in-chip critical dimension (CD), overlay metrology [9], and in-situ measurement of pattern reflow in nanoimprinting [10].…”

Development of a broadband Mueller matrix ellipsometer as a powerful tool for nanostructure metrology

“…Since the year of around 2000, spectroscopic ellipsometry (SE) was introduced to monitor the critical dimension (CD) of grating structures in semiconductor manufacturing [3][4][5]. Compared with SEM, AFM, and TEM, this technique, also referred to as optical scatterometry or optical critical dimension metrology, has achieved wide industrial applications after ten years of development due to its attractive advantages, such as low cost, high throughput, and minimal sample damage [6,7].…”

Application of measurement configuration optimization for accurate metrology of sub-wavelength dimensions in multilayer gratings using optical scatterometry

“…Optical scatterometry, which is rooted in high-precision ellipsometric measurement, is a fast, accurate, non-destructive, and non-contact metrology technique used for measuring the feature dimensions of complex grating structures [1][2][3]. Nowadays, scatterometry has become a critical technique for in-line wafer-to-wafer process monitoring and control in lithography and etch processes [4][5][6] because of its inherent advantages over conventional image-based metrology techniques, such as scanning electron microscopy and transmission electron microscopy (TEM). Scatterometry is a model-based technique where the measured optical signature is fitted by assuming a multi-parameter optical model when calculating the diffraction from a periodic grating to minimize a predefined least-squares (LSQ) function [7][8][9][10].…”