Gerardo Silva Navarro

Control of Nonlinear Active Vehicle Suspension Systems Using Disturbance Observers

Francisco Beltran-Carbajal1, Esteban Chavez-Conde2, Gerardo Silva Navarro3, Benjamin Vazquez Gonzalez1 and Antonio Favela Contreras4 1Universidad Autonoma Metropolitana, Plantel Azcapotzalco, Departamento de Energia, Mexico, D.F. 2Universidad del Papaloapan, Campus Loma Bonita, Departamento de Ingenieria en Mecatronica, Instituto de Agroingenieria, Loma Bonita, Oaxaca 3Centro de Investigacion y de Estudios Avanzados del I.P.N., Departamento de Ingenieria Electrica, Seccion de Mecatronica, Mexico, D.F. 4ITESM Campus Monterrey, Monterrey, N.L. Mexico

GaN substrates obtained by nitridation of GaAs

A new substrate for the growth of GaN by MOCVD is presented. Photoluminescence spectra show the bandgap emission and yellow luminescence. The latter can be reduced by optimizing the growth parameters. The optical properties of the films are comparable to those of layers obtained epitaxially on sapphire substrates.

Luminescence tuning in GaN layers

GaN layers were grown at low pressure by nitridation of GaAs substrates. The films showed photoluminescence when excited with ultraviolet light. The luminescence color could be tuned by adjusting the growth parameters.