Identification of Materials in Integrated Circuit Interconnects Using X-Ray Absorption Near Edge Spectroscopy

Published

January 1, 1999

Author(s)

Zachary H. Levine, Bruce D. Ravel

Abstract

Most integrated circuit interconnects are principally composed of a few metals, including aluminum alloyed with copper, tungsten, titanium, A1₃ Ti, and A1₂Cu, in a silica matrix. Integrated circuit interconnects have recently been proposed as a candidate system for visualization by computerized microtomography using absorption in the soft X-ray region. In this work, we demonstrate the feasibility of materials identification using volume-resolved X-ray absorption near edge spectra (XANES) obtained by tomographic reconstruction. A similar experiment could be performed with an energy-resolved high-voltage transmission electron microscope. We calculate the XANES for interconnect materials near the Al K edge, the Cu L_I, L_II, and L_III edges, and the Ti L_II, and L_III, and compare to experiment when possible. The signal -to- noise ratio required to distinguish among the aluminum compounds from the A1 K edge spectra is shown to be about one order of magnitude higher than that needed to detect elemental aluminum.

Citation

Journal of Applied Physics

Volume

85

Issue

No. 1

Pub Type

Journals

Keywords

integrated circuit interconnect, X-ray absorption, XANES

Citation

Levine, Z. and Ravel, B. (1999), Identification of Materials in Integrated Circuit Interconnects Using X-Ray Absorption Near Edge Spectroscopy, Journal of Applied Physics (Accessed April 19, 2024)