Methods and systems for semiconductor metrology based on polychromatic soft X-Ray diffraction

US11333621B2 · kind B2 · utility

Assignee

• KLA-TENCOR CORPORATION · US

Inventors

• Daniel Wack · Los Altos Hills, US
• Oleg Khodykin · San Diego, US
• Andrei V. Shchegrov · Campbell, US
• Alexander Kuznetsov · Austin, US
• Nikolay Artemiev · Berkeley, US
• Michael Friedmann · Nesher, IL

Key dates

• Filing date: Jul 9, 2018
• Grant date: May 17, 2022
• Expiry date: Mar 25, 2039

Classification

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

Abstract

Methods and systems for performing measurements of semiconductor structures based on high-brightness, polychromatic, reflective small angle x-ray scatterometry (RSAXS) metrology are presented herein. RSAXS measurements are performed over a range of wavelengths, angles of incidence, and azimuth angles with small illumination beam spot size, simultaneously or sequentially. In some embodiments, RSAXS measurements are performed with x-ray radiation in the soft x-ray (SXR) region at grazing angles of incidence in the range of 5-20 degrees. In some embodiments, the x-ray illumination source size is 10 micrometers or less, and focusing optics project the source area onto a wafer with a demagnification factor of 0.2 or less, enabling an incident x-ray illumination spot size of less than two micrometers. In another aspect, active focusing optics project programmed ranges of illumination wavelengths, angles of incidence, and azimuth angles, or any combination thereof, onto a metrology area, either simultaneously or sequentially.