Microelectromechanical displacement sensing using InAs/AlGaSb heterostructures

Abstract

We fabricated self-sensing microelectromechanical displacement sensors from InAs/AlGaSb heterostructures. The sensitivity increased with reduced InAs thickness showing that the piezoresistivity was strongly enhanced when the quantum level approached to the pinning position of surface Fermi level. The high-sensitivity allowed us to detect a subangstrom displacement induced by thermal vibration of cantilevers.