Excellent electric properties of free-standing InAs membranes

Abstract
We fabricated semiconducting free-standing-beam and Hall-bar structures with a high slenderness ratio, a minimum thickness of 50 nm, and a typical length of several tens of microns using InAs membranes processed from InAs/GaAs heterostructures. These structures showed clear electric conductivity without any intentional doping. We obtained the carrier concentration and mobility by means of standard Hall measurements, thus confirming that both parameters were much larger than those of as-grown heterostructure samples. These results indicate that this material system is promising for micro/nanoelectromechanical system applications.