STUDY AlxGa1-XAs EPITAXIAL LAYERS DOPED WITH Ge BY MEANS OF THE LOW TEMPERATURE PHOTOLUMINESCENCE

Study Al_xGa_1-xAs Epitaxial layers DOPED With Ge BY means of The Low Temperature photoluminescence

F. Gordillo-Delgado¹, J. A. Cardona-Bedoya¹, J. Diaz-Reyes², L. Gómez-Herrera^2,3, J.G. Mendoza-Alvarez^1,2

1 Depto. de Física-Cinvestav del IPN. Apdo. Postal 14-740. México DF 07000

^{2 CICATA-IPN. Legaria 694. Col. Irrigación. México DF 11500
^{3 Lab. de Optoelectrónica. Univ. del Quindío. A.A. 460. Armenia, Q. Colombia

Using the liquid-phase epitaxy (LPE) technique, we have grown Al_xGa_1-xAs epitaxial layers with different concentrations of Al. These layers were grown on single crystalline substrates of GaAs with (100) orientation, and they were doped with Ge to obtain films p-type for application in optoelectronic devices. The problem of diffusion of impurities in the layers with the time is of great importance because of its influence in the performance of the devices due to the reduction in their efficiency. In this work we have measured the photoluminescence (PL) spectra of these films (grown more than 5 years ago) for different temperatures and excitation powers to identify the origin of the different emission bands that appear in the PL spectra. From the analysis of these bands we will study the possible presence of Ge interstitial sites resulting from the diffusion process; that is, a process of aging of the films.}}