Device inherent IMD reproducibility issues in GaN HEMTs

This paper stresses on critical requirements for characterizing device inherent intermodulation distortion (IMD) products in power HEMTs for 3G wideband applications. An accurate broadband RF testbench is essential for reliable nonlinearity measurements. With the optimized IMD characterization testbench, the reproducibility of sweet-spot behavior in GaAs and GaN HEMT technologies has been investigated. This involved statistical process consistency evaluation of GaAs and GaN HEMT semiconductor technologies in terms of their respective pinch-off voltages characterizing sufficient device samples. Corresponding influence on the nature of sweet-spot repeatability under two-tone and multi-carrier WCDMA stimuli revealed the importance of IF load termination.