Dispersion model for band gap tracking

US10770362B1 · kind B1 · utility

Assignee

• KLA Corporation · US

Inventors

• Natalia Malkova · Mountain View, US
• Leonid Poslavsky · Belmont, US
• Ming Di · Hayward, US
• Qiang Zhao · Milpitas, US
• Dawei Hu · Shanghai, CN

Key dates

• Filing date: Aug 1, 2019
• Grant date: Sep 8, 2020
• Expiry date: Aug 1, 2039

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R31/2648
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Methods and systems for determining band structure characteristics of high-k dielectric films deposited over a substrate based on spectral response data are presented. High throughput spectrometers are utilized to quickly measure semiconductor wafers early in the manufacturing process. Optical models of semiconductor structures capable of accurate characterization of defects in high-K dielectric layers and embedded nanostructures are presented. In one example, the optical dispersion model includes a continuous Cody-Lorentz model having continuous first derivatives that is sensitive to a band gap of a layer of the unfinished, multi-layer semiconductor wafer. These models quickly and accurately represent experimental results in a physically meaningful manner. The model parameter values can be subsequently used to gain insight and control over a manufacturing process.