Double injection in semiconductor layers in a transverse magnetic field

Abstract

A theory of double injection for thin semiconductor layers in a transverse magnetic field is developed. The fundamental equation in drift approximation is analyzed for the semiconductor and insulator regimes by introducing a parameter, i.e. the local effective carrier lifetime. As a result, expressions for the layer current‐voltage characteristics are obtained. For high fields they obey the laws J ∼ U and J ∼ U2, respectively, which accounts for high magnetosensitivity. With low fields applied and at different velocities of surface recombination in the layer the effect of polar magnetosensitivity is observed. The constant Lorentz force approximation is analyzed and compared with a more precise theory.

Effect of light and magnetic field on double injection in semiconductor layers

“…Similarly to [3] let us consider an n-type homogeneous and isotropic semiconductor layer of thickness d (in the y-direction), length 1 > d (in x-direction) and width b > 1 (in z-direction). The assumption is made that the holes and electrons are injected into the semiconductor layer at x = 0 and x = I , respectively, and monochromatic light flows fall onto the y = 0 and y = d layer surfaces, for which the light absorption coefficients in the semiconductor are equal to a$ and a:, respectively.…”

“…Equation (1) differs from the one studied in [3] in additional photogeneration terms Go(y) and Gd(y) in the left-hand side. This equation will be solved un&er the boundary conditions which take into account the effect of the recombination processes taking place on the surfaces of the semiconductor layer at double injection.…”

“…The general solution of the boundary problem (1) and (5)' assuming that Q is independent of y can be represented as the sum of two terms Ap,, and Apg of which the former is the solution of (1) at gO,d = 0, and the latter is caused by the photogeneration of the charge carriers. Thus, we have Ap = Apo + Ap0 = Apo + Co(e-aaq + C Ck e ykq ) + Cd(eQ(V-l) + C Cf e y k q ) , (6) where Apo was found earlier in [3] and for the reader's convenience is given in the Appendix (cf. (A3)).…”

“…The dark conduction CT* and the effective lifetime of the charge carriers t* eff were determined earlier in [3] and are given in the Appendix (cf. (A4) and (A5)) ; r = 2 for intrinsic semiconductors and r = 1 and r = 2 for extrinsic semiconductors a t low and high injection levels, respectively.…”

“…The general equation for electric field and concentrations of the charge carriers in the layer, in drift approximation, with the light and magnetic field transverse to the full current acting simultaneously, is obtained. Besides, like in [3] account is taken of the effects quadratic with respect to the magnetic field, which occur when pP,nB ( p p , n are drift mobilities of holes and electrons and B is the magnetic field induction)…”