Method for simultaneously reducing the misalignment offset and separating the Hall voltage from the off-diagonal piezoresistive voltage in Hall effect and piezoresistive devices based on silicon

Abstract

A novel misalignment offset reduction technique is extended in order to separate a piezoresistive voltage, from the Hall voltage, in doubly connected Hall elements based on silicon. In a special configuration, this method exploits directional averaging using biaxial current injection from four electrically separate current sources in order to cancel in situ the stress-generated off-diagonal piezoresistive voltage across the Hall voltage contacts. Measurements suggest field-equivalent offsets below 1 mT in (001) surface n-Si devices with current injection in the [110] direction.