Development of Contactless Measuring Instrument for Sheet Resistance by Means of Pulse Voltage Excitation

Abstract

The sheet resistance of a silicon wafer has conventionally been measured with the four-point probe technique and/or high frequency sinusoidal magnetic excitation with a Robinson marginal oscillator as an excitation current supply. The authors propose a novel contactless method of measuring sheet resistance that utilizes a pulse voltage to generate an eddy current in the sheet under test. The novel method can measure the sheet resistance under 5 mΩ/sq., that is the smallest value the conventional contactless method can measure.