Method and device for optically monitoring fabrication processes of finely structured surfaces in a semiconductor production

US7003149B2 · kind B2 · utility

Assignees

• Semiconductor 300 GmbH & Co. KG · DE
• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Norbert Benesch · Heroldsberg, DE
• Claus Schneider · Burgsinn, DE
• Lothar Pfitzner · Erlangen, DE

Key dates

• Filing date: Jun 4, 2001
• Grant date: Feb 21, 2006
• Expiry date: Mar 17, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L22/12
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for monitoring fabrication processes of finely structured surfaces in a semiconductor fabrication includes the steps of providing reference signatures of finely structured surfaces, measuring at least one signature of a test specimen surface, comparing the measured signature with the reference signatures, and classifying the test specimen surface by using the comparison results, wherein the measurement of the reference signatures is carried out by measuring the local distribution and/or intensity distribution of diffraction images on production prototypes having a specified quality. The classification is preferably carried out here with a neural network having a learning capability and/or a fuzzy logic. Furthermore, a device for carrying out the method is provided.