This paper presents the linearity enhancement of transconductance of an improved InGaP/GaAs camel-gate field effect transistor (CAMFET) with double delta-doping channel profiles. In this device, a low doped GaAs layer together with an n(+)-GaAs and an ultra-thin p(+)-InGaP layers form a high-performance camel gate structure. Also, double delta-doping channel profiles are used to enhance the output current and transconductance. For a 1 mum x 100 mum CAMFET, a high breakdown voltage of 27 V, a maximum drain current of 770 mA mm(-1), and a broad gate voltage range larger than 4 V with the intrinsic transconductance higher than 140 mS mm(-1) are obtained. In addition, the measured unit current gain cutoff frequency f(t) is 14 GHz for the studied mesa type device. These results indicate the promise for high-performance large signal analog and digital switching, and high-frequency circuit applications. (C) 2002 Elsevier Science B.V. All rights reserved.