Abstract: A method for electrical characterization of doped silicon in a contactless fashion using high-frequency electromagnetic waves was presented. A focusing sensor was used to focus a 110 GHz microwave on the surface of a silicon wafer. The amplitude and phase of the reflection coefficient of the microwave signal were measured, by which electrical conductivity of the wafer was determined quantitatively, independent of the permittivity and thickness of the wafer. The conductivity obtained by this method agrees well with that measured by the conventional four-point-probe method.

Key words: Conductivity, Doped silicon, Microwave, Quantitative evaluation