Apparatus for Inducing High Uniaxial Compressive Stresses in Crystals

Abstract

A vise capable of exerting uniaxial forces in excess of 2×10⁹ dynes and operable between 77 and 300 K is described. The strain induced in the crystal being compressed is measured via a strain gauge bonded directly to the surface of the specimen. The applied stress may be varied smoothly to greater than 10¹⁰ dynes/cm² and a resistance bridge resolves the induced strain in the stress direction to 2×10⁻⁶. Some preliminary high stress piezoresistance data for p‐type germanium are included.