Sample preparation for electron beam testing with reactive ion etching

A practical sample preparation procedure for electron beam (EB) testing using reactive ion etching (RIE) has been developed. By highly accurate anisotropic dry etching, metal wires below dielectric layers can be exposed while successfully maintaining the electrical performance of the LSI. Applying this technique to actual EB tester analysis on specimens with multi-layer metal lines, clear voltage contrast images can be obtained. This preparation procedure greatly reduces the difficulties of acquiring EB contrast images and enables effective failure analysis with fast TAT.