GROWTH AND CHARACTERIZATION OF GaAsp-n JUNCTIONS OBTAINED BY THE CSVT TECHNIQUE USING ATOMIC HYDROGEN

Abstract

The uses of atomic hydrogen to obtain semiconductor materials has increased significantly during the last decade. First, the passivating effects of energy levels, borders of grain, and interfaces were observed. Then we observed and took advantage of the capacity that atomic hydrogen has to form elementary volatile compounds to subsequently carry out an "in situ" etch. Since 1994 [1], our research group has taken advantage of this last modality to recover volatile compounds, making an inverse chemical reaction and obtaining epitaxial growths by means of the close space vapor transport technique (CSVT). The results, obtained by low temperature photoluminiscence and Hall effect measurements, show that it is possible to obtain GaAs films with p-type conductivity [2]. The optic and electric characteristics were suitable in order to manufactures semiconductor devices. For the realization of the p-n junction diodes, we used n-type GaAs (tellurium doped); we grew p-type GaAs films (zinc doped) and we showed that it is possible to obtain light emitting diodes whose emmision is on the edge. Our work showed the I-V characteristic curves at room temperature and continuous regime. The saturation current under forward bias was obtained on the order of 10-11 Amp. Photographs are shown of the radiation patterns in the near field of the p-n junctions; some regions with nonhomogeneous light are related to the presence of regions with different electric properties.