Systems and methods for device-correlated overlay metrology

US10474040B2 · kind B2 · utility

Assignee

• KLA-TENCOR CORPORATION · US

Inventors

• Frank Laske · Weilmünster, DE
• Ulrich Pohlmann · Jena, DE
• Stefan Eyring · Weilburg, DE
• Nadav Gutman · Zichron Ya'akov, IL

Key dates

• Filing date: Jun 15, 2018
• Grant date: Nov 12, 2019
• Expiry date: Jun 15, 2038

Classification

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

Abstract

An overlay metrology system may measure a first-layer pattern placement distance between a pattern of device features and a pattern of reference features on a first layer of an overlay target on a sample. The system may further measure, subsequent to fabricating a second layer including at least the pattern of device features and the pattern of reference features, a second-layer pattern placement distance between the pattern of device features and the pattern of reference features on the second layer. The system may further measure a reference overlay based on relative positions of the pattern of reference features on the first layer and the second layer. The system may further determine a device-relevant overlay for the pattern of device-scale features by adjusting the reference overlay with a difference between the first-layer pattern placement distance and the second-layer pattern placement distance.