Published online by Cambridge University Press: 15 January 2000
We have developed a model for the calculation of the induced current due to an electron beam with an extended generation profile. Added to the absorbed and diffuse electrons in the depth distribution, the generation profile takes into account the lateral diffusion. The analytical expression of the electron beam induced current (EBIC) is obtained by solving the continuity equation in permanent regime by the Green function method. The induced current profile, obtained in the case of a ternary component (Ga0.7Al0.3As:N+/Ga0.7Al0.3As:P) sulfur doped and prepared by organometallic compounds phase vapor epitaxy method, is compared to the theoretical profiles whose analytical expressions are given by Van Roosbroeck and Bresse. The experimental current profile, measured by S.E.M provided us to calculate the diffusion length of the minority carriers: Lp = 1 µm in the N region and Ln = 1.80 µm in the P region of the ternaire component. The theoretical curve obtained from the proposed model is in good agreement with the experimental one for a surface recombination velocity of 106 cm s−1. Our results are found to be consistent compared to those obtained by other experimental techniques using the same samples.