Detecting dose and focus variations during photolithography

US8407632B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Ibrahim M. Elfadel · Laguna Niguel, US
• Ying Liu · Austin, US
• Stanislav Polonsky · Putnam Valley, US
• Amith Singhee · Bengaluru, IN

Key dates

• Filing date: Sep 14, 2010
• Grant date: Mar 26, 2013
• Expiry date: Dec 7, 2030

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70658
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A method, system, and computer usable program product for detecting dose and focus variations during photolithography are provided in the illustrative embodiments. A test shape is formed on a wafer, the wafer being used to manufacture integrated circuits, the test shape being formed using a dose value and a focus value that are predetermined for the manufacturing. A capacitance of the test shape is measured. The capacitance is resolved to a second dosing value and a second focus value using an extraction model. A difference between the dosing value and the second dosing value is computed. A recommendation is made for dosing adjustment in the manufacturing based on the difference.