The effect of a localized deformation upon the common-emitter transistor current gain

Abstract

Starting from the theory of the influence of pressure upon the semiconductor band diagram, and the Kroemer's proof of existence of different forces F n and F p acting upon the electrons and holes, a system of equations is given which defines the band diagram configuration of a p- n junction in thermal equilibrium after a deformation is applied. Results of the mentioned consideration have been used to obtain expressions for the injected minority carrier currents, generation-recombination currents and the current gain β of a common-emitter transistor. Results of the experimental work, giving the relationship between the current gain β and the force F, as well as other parameters ( p- n junction depth, curvature radius of the needle, etc.), show a very good quantitative accordance with the theoretical considerations.