Characterization of annular-structure RF LDMOS transistors using polyharmonic distortion model

An annular-structure lateral-diffused metal-oxide semiconductor (LDMOS) RF transistor with polyharmonic distortion (PHD) model characterized by nonlinear vector network analyzer is described in this paper. The devices were fabricated using a 0.5 mum LDMOS process. The DC, small-signal, and large-signal characteristics of RF LDMOS transistors with annular-structures were also studied in this work. Using the PHD model, the accuracy of intermodulation and time waveform is verified. Furthermore, the model via X-parameter shows good agreement without optimization.