X-ray metrology for advanced microelectronics

CEA-LETI, Minatec, 17 rue des Martyrs, 38054 Grenoble, France

Corresponding author: cwyon@cea.fr

Received: 31 July 2009
Accepted: 25 November 2009
Published online: 26 January 2010

Abstract

The recent development of bright X-ray sources, reliable X-ray focusing optics, large X-ray detectors and X-ray data modelling and processing, have improved X-ray techniques to the point where many are being introduced in MOS transistor manufacturing lines as new metrology methods. The fundamental X-ray physical properties, such as their small wavelength and their weak interaction with solid-state matter satisfy basic in-line metrology requirements: non-destructiveness, speed, accuracy, reliability and long-term stability. The capability of X-ray based metrology methods to monitor critical 65 and 45 nm processes such as ion implant, nitrided SiO₂ gate dielectrics, NiSi, Cu/porous low-κ interconnects and MIM capacitors is highlighted in this paper.