The paper presents the electrical properties of a newly designed single delta-doped InGaP/InGaAs/GaAs pseudomorphic high electron mobility transistor (HEMT) with n(+)-GaAs/p(+)-InGaP/n-InGaP camel-like gate structure. For a 1 x 100 mum(2) device, the experimental results exhibit an extrinsic transconductance of 85 mS mm(-1) and a saturation current density of 425 mA mm(-1). Significantly, due to the p-n depletion from p(+)-InGaP gate to channel region and the presence of considerable conduction band discontinuity at InGaP/InGaAs heterostructure, the gate-to-drain turn-on voltage is larger than 1.7 V In addition, an extremely broad gate voltage swing larger than 3 V with above 80% maximum g(m) is obtained. The unit current cutoff frequency f(T) and maximum oscillation frequency f(max) are up to 18 and 30 GHz, respectively. (C) 2003 Elsevier B.V. All rights reserved.