Nonlinearity study of double and single channel GaAs HEMTs

In this paper the intrinsic transconductance, output current, output power and their nonlinear derivatives are analyzed for double and single channel HEMTs. It is shown that the distortion products weakly depend on device´s gate width dimension. Conversely, it is strongly affected by the 2DEG sheets in the quantum wells. The more the number of device´s active channels, the higher the current and subsequently the lower the percentage of distortion. As the input power level increases, the amplitude of the input signal increases and the this adds to input voltage of the device which controls the thickness of the layer where the electrons flow. This affects the output levels, leading the notch of third order harmonic to appear at higher output current.