The double-delta-doped In-0.5(Al0.7Ga0.3)(0.5)P/GaAs/In0.3Ga0.7As field-effect transistors (FETs) epitaxial layers were grown on (100)-oriented semi-insulating GaAs substrate using low-pressure metalorganic chemical vapor deposition system. To study the characteristics of the FETs with and without illuminating of laser beams of various wavelengths, we find that both I-DS-V-DS characteristics and g(m)-V-Gs characteristics have not been affected by the excitation for the laser beam of the wavelength 841 and 1324 nm; while a slightly influence for the 632.8 nm laser beam. We also study the high frequency response of the fabricated devices. (C) 2002 Published by Elsevier Science Ltd.