Carrier Concentration Gradient Research Articles

Influence of carrier concentration gradients and mobility gradients on galvanomagnetic effects in semiconductors

Phenomenological theory of galvanomagnetic effects is given in the case of extrinsic semiconductors when gradients of carrier concentration and mobility are parallel to the magnetic field and perpendicular to the electric field. Applications to the diffused and epitaxial layers are possible. Comparison of theoretical and experimental results on an InSb-copperplated sample is presented.

Influence of Conductivity Gradients on Galvanomagnetic Effects in Semiconductors

An approximate solution is found of a boundary-value problem arising from the continuity equation in an inhomogeneous semiconductor, leading to rotational current vectors. Results are used to predict the effect of carrier-concentration gradients on magnetoresistance. The predicted weak-field effects are especially significant in degenerate semiconductors and n-type III–V intermetallics where the ``intrinsic'' magnetoresistance is small. In strong fields, even small gradients in carrier concentration can completely alter the field dependence of the magnetoresistance. Experimental results indicate that transverse currents, which do not occur in the simple case discussed, do appear in general, and further perturb the magnetoresistance. The influence of inhomogeneous magnetic fields is discussed briefly.