Critical dimension metrology by through-focus scanning optical microscopy beyond the 22 nm node

Published

June 7, 2013

Author(s)

Ravikiran Attota, Benjamin D. Bunday, Victor Vertanian

Abstract

We present results using simulations and experiments to demonstrate metrological applications of the through-focus scanning optical microscopy (TSOM) down to features at and well below the International Technology Roadmap for Semiconductors' 22 nm node. The TSOM method shows the ability to detect sub-nanometer, three-dimensional shape variations such as line height, sidewall angle, width, and pitch in fins of fin-shaped field effect transistor structures using conventional optical microscopes. In addition, the method requires targets substantially smaller than the conventional target size. These results provide insight into the applicability of TSOM for economical critical dimension and yield enhancement metrology.

Citation

Applied Physics Letters

Pub Type

Journals

Keywords

TSOM, Through-focus scanning optical microscopy, nano-metrology, FinFET, CD, critical dimension, optical microscopy

Citation

Attota, R. , Bunday, B. and Vertanian, V. (2013), Critical dimension metrology by through-focus scanning optical microscopy beyond the 22 nm node, Applied Physics Letters (Accessed October 15, 2025)