A new test structure for the electrical measurement of the width of short features with arbitrarily wide voltage taps

摘要

Accurate determination of the linewidth of a narrow conducting film for VLSI applications using electrical test structure metrology has required that the length of the line be many times its width to minimize geometric error due to the finite width of the voltage taps. However, long lines obscure important local effects such as nonuniformities in the film. Shorter lines highlight such effects. This work describes a method of measuring the width of a short line having taps of arbitrary width. The effect of the taps is measured and used in the extraction of the linewidth allowing the determination of local linewidth variations with confidence.