Critical Dimension Measurement Using OCD Spectroscopy for Gate and STI AEI Structures

Abstract

In this work, optical critical dimension (OCD) spectroscopy was used to monitor the critical dimension for gate and STI AEI (After-Etch Inspection) structures. The reference measurements with CD-SEM (CD Scanning Electron Microscope) and TEM (Transmission Electron Microscopy) were also carried out. The OCD results show high precision, high stability and good correlation. This work demonstrates the capability of the OCD as an important metrology technique for IC process control.