Stress in Thin Layers Applied by Substrate Bending; Calibration and Potentialities

Abstract

ABSTRACTUniaxial stresses up to 0.3GPa, both compressive and tensile, can be generated in thin epitaxial layers by substrate bending. We demonstrate the feasibility of the method and calibrate the stress, measuring piezoresistance at temperatures below the impurity freeze-out, on lightly B-doped silicon MBE layers, using the known expression for a surface stress in a bent cantilever beam. The ground state energy displacement of B in Si thus obtained can vary by ±5meV, suggesting potential applications of the technique in tunable devices, involving doped semiconductors or heterostructures.